Academic literature on the topic 'Seedling quality'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Seedling quality.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Seedling quality"

1

Ekamawanti, Hanna Artuti, Lenawati Simanjuntak, and Abdurrani Muin. "Assessment of the Physical Quality of Eucalyptus pellita Seedlings from Shoot Cutting by Age Level." Jurnal Sylva Lestari 9, no. 2 (2021): 280. http://dx.doi.org/10.23960/jsl29280-290.

Full text
Abstract:
The criteria for target seedling of Eucalyptus pellita F. Muell are at least 90days old, with consequences for the length of stay of the seedlings in the nursery. This study must assess the suitability as a target seedling first if it wants to plant the seedlings under 90days old in the field. The research aimed to evaluate and obtain the regression equation for the seedling’s age with the seedling’s morphological characters. The shoot seedlings cuttings aged 45, 60, 75, and 90 days after planting in the cocopeat growing medium were assessed. The study was used a survey method with a purposive sampling technique to obtain 60 samples by assessing the growth and appearances of the seedling. Furthermore, 15 samples were taken at random to determine the dry weight of the seedlings. Seedlings aged 75 and 90 days indicated the standard criteria as target seedlings for height, diameter, number of leaves, seedling’s health, shoot appearances, and seedling roots. The two seedlings’age levels have a sturdiness index of 8.34-9.78; shoot-root ratio 3.9-4.5; and seedling quality index (SQI) 0.22-0.23. Seedling age had a powerful positive correlation with the sturdiness index and SQI (r = 0.84 and r = 0.96). The regression equation of the sturdiness index is y = 0.048x + 5.435 (R2 = 0.996) and SQI is y = 0.004x - 0.064 (R2 = 0.926). This research implies that 75 and 90-days seedlings can be considered as one of the criteria for the age of E. pellita shoot cuttings as the target seedling in the SOP of PT. Finnantara Intiga.Keywords: cocopeat, Eucalyptus pellita, Seedling Quality index, shoot cuttings, target seedling
APA, Harvard, Vancouver, ISO, and other styles
2

Yücedağ, Cengiz, Nebi Bilir, and Halil Barış Özel. "Phytohormone effect on seedling quality in Hungarian oak." Forest Systems 28, no. 2 (2019): e005. http://dx.doi.org/10.5424/fs/2019282-14604.

Full text
Abstract:
Aim of study: to find out the effects of four phytohormones, including Indole Butyric Acid (IBA), Indole Acetic Acid (IAA), and Gibberellic acids (GA3, GA4) on seedling growth of Hungarian oak which has a natural distribution in the northwestern of Turkey.Area of Study: Mature acorns of Hungarian oak were collected from a natural stand in Zonguldak-Ereğli at northwestern region of Turkey.Material and Methods: Collected acorns of the species were pretreated with 300 ppm of each phytohormone for 24 hours and sown in Yenihan State Forest Nursery of Bartin, Turkey. Two years old bare-root seedlings were used for the measurements of seedling height, root collar diameter, stem, root and seedling fresh weights, and stem, root and seedling dry weights of two bare-root seedlings for each phytohormone treatment.Main results: Best performance of all studied seedling traits with the exception of root collar diameter was revealed in seedlings with IBA. In contrast, treatment of seeds with GA3 reduced all seedling traits apart from seedling height and root collar diameter. According to Dickson quality index, IBA was displayed to be the most beneficial phytohormone application for generating Hungarian oak seedlings with better mechanical resistance during transplanting.Research Highlights: IBA should be adopted in planting the seedlings of Hungarian oak for plantation activities.
APA, Harvard, Vancouver, ISO, and other styles
3

McCreary, Douglas D., and Joe B. Zaerr. "Root respiration has limited value for assessing Douglas-fir seedling quality." Canadian Journal of Forest Research 17, no. 9 (1987): 1144–47. http://dx.doi.org/10.1139/x87-175.

Full text
Abstract:
Root damage is a principal cause of poor seedling quality. Currently, the most widely used seedling-quality test measures a seedling's ability to initiate and elongate roots in a favorable environment; however, this test requires a lengthy response period and tedious, time-consuming measurements. Alternatively, the respiration rate of roots could be measured much more quickly and easily. Results of this study, which examined whether root respiration could successfully predict the survival and growth of potted Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings in a growth room, indicated that respiration may help assess root damage caused by desiccation but not that caused by freezing, hot storage, or rapid heating.
APA, Harvard, Vancouver, ISO, and other styles
4

Ren, Yun, Jianfang Zhu, Nazim Hussain, et al. "Seedling age and quality upon transplanting affect seed yield of canola (Brassica napus L.)." Canadian Journal of Plant Science 94, no. 8 (2014): 1461–69. http://dx.doi.org/10.4141/cjps-2014-021.

Full text
Abstract:
Ren, Y., Zhu, J., Hussain, N., Ma, S., Ye, G., Zhang, D. and Hua, S. 2014. Seedling age and quality upon transplanting affect seed yield of canola (Brassica napus L.). Can. J. Plant Sci. 94: 1461–1469. Seedling quality is an essential indicator for seed yield in canola, which is affected by many factors, including seedling age. Two field experiments were conducted to compare canola seedling quality and seed yield on 30-, 35-, 40-, 45-, 50-, 55-, and 60-d-old seedlings in 2011 and 2012. The relationship between seedling quality traits and seed yield of different seedling ages was also analyzed. Results revealed that the highest seed yield obtained from 40-d-old seedlings was attributed to more branches and siliques per plant. The negative effect of young seedlings (30-d-old) on seed yield was greater than that of old seedlings (60-d-old). The reduction rates in seed yield on the 30- and 60-d-old seedlings were 25.7 and 18.2%, respectively, compared with the 40-d-old seedlings. Increased root neck diameter, green leaf number, shoot, and root dry matter was the case on 40-d-old seedling transplanted plants compared with other ages. However, the increase was larger in the old seedlings than in the young seedlings. On average, the shoot and root dry weights of the 30-d-old seedlings were 1.9 and 1.7% of those in the 60-d-old seedlings. However, correlation analysis revealed that the seedlings with the highest shoot and root dry matter did not necessarily obtain the highest seed yield. Factor analysis suggested that the effects of root neck diameter and green leaf number on seed yield were more pronounced than those of shoot and root dry matter. Therefore, high seed yield in canola could be defined in terms of optimum green leaf numbers and branches per plant.
APA, Harvard, Vancouver, ISO, and other styles
5

Dranski, João Alexandre Lopes, Ubirajara Contro Malavasi, and Marlene de Matos Malavasi. "RELATIONSHIP BETWEEN LIGNIN CONTENT AND QUALITY OF Pinus taeda SEEDLINGS1." Revista Árvore 39, no. 5 (2015): 905–13. http://dx.doi.org/10.1590/0100-67622015000500013.

Full text
Abstract:
ABSTRACT The essay objective was to correlate lignin content resulting from tigmomorphogenesis induced by stem swaying with survival and post-planting growth of P. taeda seedlings. Seedlings were subjected to daily frequencies (0, 5, 10, 20 and 40 movements) of stem swaying for 60 days. By the end of the treatments, we determined lignin content of below and aboveground seedling tissues. Four replicates per treatment were planted in a area cultivated with pines. Ninety days after planting, survival and increments of seedling height, stem diameter and stem volume were quantified. Application of 20 stem swayings increased lignin in both below and aboveground plant tissues. Outplanted seedling survival was reduced with 40 stem swayings while growth increments were increased with both 10 and 20 stem swayings. Lignin content from belowground plant tissues was positively correlated with outplanted seedling survival while lignin from aboveground tissues correlated with height and stem volume increments. P. taeda seedlings with higher lignin content have higher survival chances after planting.
APA, Harvard, Vancouver, ISO, and other styles
6

Zuo, Qingsong, Jingjing You, Long Wang, et al. "A Balanced Sowing Density Improves Quality of Rapeseed Blanket Seedling." Agronomy 12, no. 7 (2022): 1539. http://dx.doi.org/10.3390/agronomy12071539.

Full text
Abstract:
Mechanized transplanting of rapeseed (Brassica napus L.) blanket seedling is an effective strategy to cope with the seasonal conflict and large labor cost in rapeseed production. The sowing density is a key factor to cultivate high-quality seedlings suitable for mechanized transplanting. An experiment was conducted to investigate the effects of different sowing density levels of 638, 696, 754, 812, 870 and 928 seeds per tray (referred as D1, D2, D3, D4, D5 and D6, respectively) on agronomic traits and survival rate after mechanized transplanting of two rapeseed cultivars (Zheyouza108 and Heza17) in 2020 and 2021. The results showed that high sowing density increased plant height but decreased leaf area, collar diameter, biomass accumulation, the ratio of root to shoot and seedling fullness. These negative effects jointly decreased the seedling rate and survival rate after mechanized transplanting. However, the seedlings under D1 and D2 posed a great plant survival rate of more than 95% after mechanized transplanting, suggesting that the seedlings under the two densities were perfect for mechanized transplanting. In addition, hierarchical analysis grouped D1 and D2 into the same class, indicating that their seedling qualities were not significantly different, though the blanket seedlings under D1 outperformed those under D2 in some traits. A sowing density of 696 seeds per tray (D2) is then recommended in this study, altogether considering its high-quality seedlings suitable for mechanized transplanting, and economically, fewer seedling trays required.
APA, Harvard, Vancouver, ISO, and other styles
7

Robonen, Elena V., Nadezhda P. Chernobrovkina, Anastasiya V. Egorova, Karina G. Nelaeva, and Maria I. Zaitseva. "Morphometric Criteria for Assessing the Containerized Conifers Seedlings Quality." Lesnoy Zhurnal (Forestry Journal), no. 5 (November 1, 2023): 42–57. http://dx.doi.org/10.37482/0536-1036-2023-5-42-57.

Full text
Abstract:
The quality of planted forest crops depends significantly on the qualities of the planting stock. Numerous studies have been carried out to find clear seedling quality criteria and work out methods for their quantitative assessment to optimize the cultivation regime. Indicators of planting stock that are available for measurement under nursery conditions are needed to predict the success of forest crop establishment. This paper provides a review of the studies that applied different morphological criteria to evaluate coniferous planting stock quality and different determination methods. The suitability of planting stock quality indicators is determined by the effectiveness of predicting the outplanting survival rate (%) and growth. The key morphometric attributes of planting stock are the linear dimensions and biomass of whole seedlings and their individual organs: root collar diameter (RCD), seedling height (SH), dry mass of needles (NDM), stem (SBDM), roots (RDM), shoot/aboveground part of the seedling (SDM), seedling’s total dry matter (TDM), number of needles (NN). Effective indicators of seedling quality are morphometric indicators of roots: total length (TRL), volume (TRV), dry mass (RDM), number of first- (FOLR N), second- (SOLR N), and third-order (TOLR N) lateral roots, root surface area (TRS). TRL is a fairly reliable indicator of absorbent surface area. To minimize errors in the use of one or two traits, integrated seedling quality indices based on two or more indices have been developed. Widely used indices include: SQ = SH(cm)/RCD(mm); SDM/RDM ratio; Dickson quality index DQI = TDM/ ((SH / RCD) + (SDM / RDM)). RCD was the most suitable parameter to indicate seedling quality for many species due to its higher correlation level with the Dickson quality index. The SH index proved to be an effective indicator for analysis only when used together with RCD. When studying the formation of frost resistance, a number of morphological parameters are used: initiation of needle primordia, size of primordial shoots, cell volume, mitotic index (MI) of terminal primordia. Despite advances in testing planting stock quality and predicting field performance, not a single test is universally applicable for all woody plant species and environmental conditions. According to the target seedling concept, the application of morphometric criteria for assessing seedling quality in forest nurseries is a prerequisite for predicting outplanting success and maximizing the predictability of the outcomes of highproductivity forest crop planting. For citation: Robonen E.V., Chernobrovkina N.P., Egorova A.V., Zaitseva M.I., Nelaeva K.G. Morphometric Criteria for Assessing the Containerized Conifers Seedlings Quality. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 42–57. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-42-57
APA, Harvard, Vancouver, ISO, and other styles
8

Zhang, Xu, Jinxin Peng, Xiaodong Hao, et al. "Serratia marcescens LYGN1 Reforms the Rhizosphere Microbial Community and Promotes Cucumber and Pepper Growth in Plug Seedling Cultivation." Plants 13, no. 5 (2024): 592. http://dx.doi.org/10.3390/plants13050592.

Full text
Abstract:
The vegetable plug seedling plays an important role in improving vegetable production. The process of plug seedling contributes to high-quality vegetable seedlings. The substrate composition and chemical fertilizer are widely studied to promote seedling growth. However, little is known about the effect of beneficial bacteria in the rhizosphere microbial community and vegetables’ growth during plug seedling. The use of beneficial microbes to promote vegetable seedling growth is of great potential. In this study, we showed that the Serratia marcescens strain LYGN1 enhanced the growth of cucumber and pepper seedlings in plug seedling cultivation. The treatment with LYGN1 significantly increased the biomass and the growth-related index of cucumber and pepper, improving the seedling quality index. Specifically, LYGN1 also improved the cucumber and pepper root system architecture and increased the root diameter. We applied high-throughput sequencing to analyze the microbial community of the seedlings’ rhizosphere, which showed LYGN1 to significantly change the composition and structure of the cucumber and pepper rhizosphere microbial communities. The correlation analysis showed that the Abditibacteriota and Bdellovibrionota had positive effects on seedling growth. The findings of this study provide evidence for the effects of Serratia marcescens LYGN1 on the cucumber and pepper rhizosphere microbial communities, which also promoted seedling quality in plug seedling cultivation.
APA, Harvard, Vancouver, ISO, and other styles
9

Lazuardi Santoso, Rizky, Indriyanto Indriyanto, and Ceng Asmarahman. "The Quality of Tree Seedlings in The Nursery Owned by PT Bukit Asam, Tarahan Port Unit, Bandar Lampung City, Lampung Province, Indonesia." Journal of Research in Agriculture and Animal Science 11, no. 11 (2024): 08–17. https://doi.org/10.35629/9459-11110817.

Full text
Abstract:
Rehabilitation of post-coal mining land and other land that has been used as a site for a series of mining activities requires seedlings of adequate quantity and quality. Therefore, research on the quality of tree seedlings in the nursery owned by PT Bukit Asam was carried out to determine the physical-physiological condition and classification of the quality of the seedlings. Observations were made on 10 sample seedlings which taken randomly from each tree species. The data collected consists of tree species, seedling height, stem diameter, straightness of the stem, length of the woody stem, number of leaves and/or live crown ratio, compactness of the growing medium, and health condition of the seedling. The seedling quality analysis was carried out based on the criteria that listed in the Indonesian National Standards (INS). The results of the research show that tree species which its seedling meet the standard criteria for normal seedlings are 11 species or 68.75% of all trees species. There are no species of tree seedlings in the first quality category (F). There are 6 species of tree seedlings in the second quality category (S) or 37.50% of the total number of trees species. There are 5 species of non-quality tree seedlings or 31.25% of the total number of trees species. Meanwhile, there are 5 species of tree seedlings which quality criteria are not listed in INS.
APA, Harvard, Vancouver, ISO, and other styles
10

Hossen, MA, MM Hossain, ME Haque, and RW Bell. "Effect of Seed Rate on Seedling Quality for Mechanical Rice Transplanting." Bangladesh Rice Journal 22, no. 1 (2019): 9–23. http://dx.doi.org/10.3329/brj.v22i1.41834.

Full text
Abstract:
A study was conducted in the Farm Machinery and Postharvest Technology Division, Bangladesh Rice Research Institute (BRRI), Gazipur in the irrigated dry season (Boro) of 2012-13. It was aimed at identifying the optimum seed rate of different graded rice variety for mat type seedlings preparation and suitable seedling adjustment option of the rice trans planter to maintain required number of seedlings dispensed per stroke by the rotary picker of the trans planter. Walk behind type 4-rows rice trans planter (DP 480) was used to conduct the study. The experiment was followed as two factorial completely randomized design (CRD) with three replications. Three categories of rice variety as short and bold grain (cv. BR3), medium and slender grain (cv. BRRI dhan28) and extra-long and slender grain (cv. BRRI dhan50) were considered as main factor whereas seed rate of 100, 120, 130, 140, 150 and 160g pertray (280×580×25 mm) were considered as sub-factor. Irrespective of rice category, seedling emergence decreased with the increase of seed rate. Seedling emergence decreased from 77 to 56, 74 to 57 and 77 to 54% in BR3, BRRI dhan28 and BRRI dhan29 respectively with the increase of seed rate from 100 to 160g per tray. Seed rate did not affect the seedling height significantly whereas it was varied with the rice verities only and BRRI dhan50 produced higher seedling length. However, number of leaf, stem thickness and shoot dry weight decreased and root-shoot ratio increased significantly with the increase of seed rate. The highest shoot dry weight was observed in BR3 followed by BRRI dhan50. Seedling strength also decreased with the increase of seed rate. The highest seedling strength (0.043 mg cm-1) was observed for the seed rate of 100g of BR3 and the lowest (0.020 mg cm-1) for the seed rate of 160g of BRRI dhan28. The number of seedling increased and percentage of missing hills decreased with the increase of both the seed rate and seedling adjustment option of the rice transplanter irrespective of variety. In case of BR3, seedling dispensed per stroke and percentage of missing hills varied from 4.3 to 5.7 and 6.8 to 7.8 for the seed rates of 140, 150 and 160 g of seeds tray-1 for 5 to 7 seedling adjustment option of the rice transplanter respectively. Seedlings per stroke and percentage of missing hills of BRRI dhan28 for the seed rate of 130, 140 and 150 g of seeds tray-1 was found almost same for 5 to 7 seedling adjustment options of the rice transplanter (4.2 to 6.3 and 5.7 to 9.8). However, there was minimum difference of seedlings per stroke and percentage of missing hills among 120, 130 and 140 g of seeds tray-1 for the option of 4 to 7 (4.0 to 5.6 and 3.9 to 7.8 respectively) for BRRI dhan50. It can be concluded that 140 g of seeds tray-1 for short and bold grain (BR3) and 130 g of seeds tray-1 for medium and slender grain (BRRI dhan28) under the seedling adjustment options of 5 to 7 and 120 g of seeds tray-1 for extra-long and slender grain (BRRI dhan50) under the seedling adjustment options of 4 to 7 may be used for desired seedlings per hill and minimum missing hills along with good quality of seedling.
 Bangladesh Rice j. 2018, 22(1): 9-23
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Seedling quality"

1

Stomph, Tjeerd Jan. "Seedling establishment in pearl millet (Pennisetum glaucum (L.) R.Br.) : the influence of genotype, physiological seed quality, soil temperature and soil water." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276632.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Rosam, Jodie Ray. "Assessment of light quality, variability, and seedling presence in Hawaiian lowland wet forests." Thesis, University of Hawai'i at Hilo, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1596447.

Full text
Abstract:
<p>Hawaiian lowland wet forest (HLWF) plant species are light-limited, yet no information exists on how the understory light varies in relation to species invasion, or if patterns of seedling regeneration and light are linked. I measured the red-to-far-red ratio (R:FR) of light to assess light quality and quantified diurnal variability in three forest types: native-dominated, partially-invaded, and fully invaded by strawberry guava (Psidium cattleianum). I asked: (1) how does understory light quality vary relative to invasion? (2) Are there differences in light quality moving vertically among forest types? (3) Are patterns of seedling regeneration and understory light related? Native-dominated forests had the greatest light quality (highest R:FR), and Psidium cattleianum-dominated forests had the lowest. While I predicted that native seedlings would prefer high-quality light sites, all seedlings preferred medium quality environments. In invaded HLWF, native seedling regeneration is hindered, and restoration efforts should focus on non-native understory removal.
APA, Harvard, Vancouver, ISO, and other styles
3

Ali, Md Gous. "The effects of low temperature and seed quality on the germination of fifteen rice (Oryza sativa L.) cultivars from Bangladesh." Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369730.

Full text
Abstract:
The responses of 15 rice cultivars to low temperature during germination were studied in order to develop appropriate techniques to identify rice genotypes suitable for direct-wet seeding in the cooler <I>Boro</I> season. Most rice cultivars showed more than 90% final germination over a range of temperatures. When tested at 13.7°C, cultivars differed in their final germination and rate of germination. The rates of germination at higher temperatures were significantly related to the rates of germination at lower temperatures. Thermal times to 50% final germination also differed significantly. Artificial ageing for 48 hours clearly separated the cultivars which had different K<sub>i</sub><I> </I>(initial seed viability). Such measures of physiological age and their relationship with final germination suggested that low quality seed exhibited reduced low temperature germination. Differences in rates and final germination at lower temperature of unaged seed suggested genotypic differences between cultivars. Inconsistency in rates of seed deterioration was seen contrary to conventional theory. Storage of seeds up to 9 weeks in simulated Bangladeshi conditions showed reductions in final germination tested at 11°C but not at 20°C. The rates of chitting and germination were increased by pregermination hydration treatments. Emergence of rice cultivars from soil was greater in constant than in alternating temperatures. Higher final emergence was associated with faster emergence. Thermal time to 50% and 80% emergence differed between cultivars. Many of the seedling growth parameters were higher in constant temperatures where the rate of germination was faster. The outcome of these experiments is to highlight the potential for comparing rates of germination of large numbers of genotypes relatively rapidly at higher temperatures as a measure to predict germination at lower temperatures.
APA, Harvard, Vancouver, ISO, and other styles
4

Howe, Alexander Addison. "Assessment of a Seedling-Based Approach to Aspen Restoration in the Intermountain West." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7062.

Full text
Abstract:
Quaking aspen (Populus tremuloides) is an important species ecologically and culturally in the western U.S., where it is one of the only broadleaf trees in the mostly conifer-dominated forests. Aspen management in the West has focused on regenerating existing stands vegetatively through root suckering, however this approach is restricted to locations where aspen currently exists and limits the genetic diversity of aspen populations. Planting nursery-grown aspen seedlings offers a potential method for overcoming these limitations, but it has received little attention in the U.S. Intermountain West (IW) to date. In order for this approach to be more broadly implemented, nursery protocols designed to grow high-quality aspen seedlings are needed, along with an understanding of what the major challenges to seedling establishment will be. With the assistance of my committee, my research tested a seedling-based approach to aspen restoration in an IW context in two phases. I first used nursery protocols developed for boreal aspen to grow seedlings collected from IW sources in order to assess whether modification of the protocols would be necessary. I then planted the seedlings I grew at three sites in southwestern Utah and monitored their growth and survival over two years. Results from the nursery phase suggest that protocols will need to be modified in order to produce a more consistent response from IW aspen seedlings. In the field, only 10% of the seedlings survived, though the majority of survival occurred in just two locations where soil moisture remained highest during the driest part of the early summer. These results provide useful information to direct future research and suggest that with a better understanding of appropriate site selection, seedling-based aspen restoration could still become a viable management tool in the IW.
APA, Harvard, Vancouver, ISO, and other styles
5

Chia, Po-Lung. "End-of-day Far-red Light Quality and Dose Effects on Elongation of Tomato Rootstock Seedling Hypocotyls." Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/193454.

Full text
Abstract:
Methyl bromide fumigation, a common method used to combat soil borne pathogens in commercial tomato cultivation, was to be limited by the Montreal Protocol due to concerns of ozone depletion. Alternative methods to protect tomatoes against diseases include grafting. However, short grafted transplants may expose the scion to the soil. To avoid scion exposure, hypocotyl elongation of two tomato rootstocks 'Maxifort' and 'Aloha' via end-of-day far-red (EOD-FR) was examined in terms of light quality (red to far-red ratio, or R/FR) and dose (product of far-red intensity and duration). In EOD-FR light quality experiments, 'Aloha' seedlings were exposed to unfiltered and filtered incandescent light with an R/FR of 0.5 and 0.05 respectively. The resulting hypocotyl elongation was higher in filtered light than either the unfiltered light or the untreated control. Hypocotyl elongation response to EOD-FR dose in 'Aloha' and 'Maxifort' was affected by both far-red intensity and treatment duration. A saturating response was also found within a far-red dose between 0–8 mmol•m⁻²•d⁻¹ and modeled using non-linear regression with a three parameter Michaelis-Menten equation to estimate the far-red dose required to obtain near-maximum hypocotyl elongation for 'Aloha' and 'Maxifort'. The far-red dose required was affected by cultivar and experimental period. None of the EOD-FR treatments affected plant mass or stem diameter. To conclude, for maximum hypocotyl elongation using EOD-FR, the lower R/FR would increase the effectiveness of the treatment. The far-red dose should preferably be at 4–8 mmol• m⁻²•d⁻¹.
APA, Harvard, Vancouver, ISO, and other styles
6

Parajuli, Suman. "Influence of Tomato (Solanum lycopersicum L.) Seedling Grafting on Plant Growth, Fruit Yield and Quality, and Disease Tolerance." Thesis, North Dakota State University, 2019. https://hdl.handle.net/10365/31651.

Full text
Abstract:
Influence of tomato (Solanum lycopersicum L.) seedling grafting on the plant growth, fruit yield and quality, and disease tolerance were investigated using 3 cultivars (Big Beef, Celebrity, Cannonball) as scions and two Solanum species (B-blocking, Maxifort) as a rootstock in a randomized complete block design with three replications. The grafted plants were statistically higher in values for stem diameter, leaf chlorophyll, and fruit carotenoid contents. Similarly, the scion/rootstock combination ‘Big Beef/Maxifort’ and ‘Big Beef/B-blocking’ had prolonged days to maturity and gives a higher yield than the non-grafted ‘Big Beef’. Grafting seedling on ‘Maxifort’ and ‘B-blocking’ rootstocks improves the fruit quality like titratable acidity (TA), fruit firmness, but didn’t alter the pH, total soluble solid (TSS), lycopene and TSS/TA. Also, grafted treatment ‘Big Beef/Maxifort’ was found to be a highly disease resistant treatment when compared to the ‘Big Beef’ control with mean relative effect 0.074.
APA, Harvard, Vancouver, ISO, and other styles
7

Ertle, John Michael. "Effects of Short-term Chilling Stress on Seedling Quality and Post-transplanting Growth of Grafted and Nongrafted Watermelon." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1594742774066127.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Breen, Amanda Nicole. "Improving seedling establishment on the saline playa at Owens Lake, California through soil amendment, improved seed quality, and increased seed entrapment /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Góes, Glêidson Bezerra de. "Propagação do tamarindeiro (Tamarindus indica L.) e da pitombeira (Talisia esculenta Raldk) por enxertia." Universidade Federal Rural do Semi-Árido, 2011. http://bdtd.ufersa.edu.br:80/tede/handle/tede/97.

Full text
Abstract:
Made available in DSpace on 2016-08-12T19:15:32Z (GMT). No. of bitstreams: 1 GleidsonBG_DISSERT.pdf: 786514 bytes, checksum: 3ae91ac265c5ddc3749833a77978d949 (MD5) Previous issue date: 2011-02-04<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>Due to the broad market prospects for crops in tamarind and pitombeira, it becomes essential the evaluation of methods that permit the propagation on a commercial scale. Considering this, two experiments were organized in a greenhouse, located in the Universidade Federal Rural do Semiárido UFERSA, located in the town of Mossoró, RN, from January 2009 until June 2010, with the objective of determining the best grafting method for the production of seedlings of tamarind and pitombeira. We studied the types of grafting: grafting in top cleft, cleft grafting in the top simple English way , grafting in the top complicated English way , grafting budding side and plate cleft. The design used in the experiments was a randomized complete block with five treatments (grafting types). The experiment with tamarind had seven repetitions; each parcel consisted of 14 seedlings, a total of 98 per treatment, adding 490 in the experiment. Variables were evaluated: percentage of grafting success, shoot length, root length, branch length, number of leaves, number of branches, stem diameter, shoot dry matter, root dry matter, Total matter dry. The data were subjected to analysis of variance and compared through the Tukey test at 5% significance using the software SISVAR. The rates of graft takes were submitted to angular transformation of arcsen &#8730; x/100, and data on the number of branches in &#8730; x + 0.5. In order to promote the statistic, treatment of pimple on board was disregarded, considering that this treatment has zero index of plant take. The grafting methods in top cleft, cleft grafting in the English top grafting complicated and simple English way in the top, are respectively the best methods of grafting for the tamarind. The test was conducted with pitombeira with four replications and each plot was composed of twenty seedlings in a total of 400 seedlings on the experiment, in which was observed zero rate of grafting take<br>Devido às amplas perspectivas de mercado para as culturas do tamarindeiro e pitombeira, torna-se indispensável a avaliação de métodos que permitam a propagação em escala comercial. Diante disso, foram desenvolvidos dois experimentos em casa de vegetação, localizada no Campus da Universidade Federal Rural do Semiárido UFERSA, situada na cidade de Mossoró-RN, no período de janeiro de 2009 a junho de 2010, com o objetivo de determinar o melhor método de enxertia para a produção de mudas de tamarindeiro e de pitombeira. Foram estudados os tipos de enxertia: garfagem no topo em fenda cheia, garfagem no topo à inglesa simples, garfagem no topo à inglesa complicada, garfagem em fenda lateral e borbulhia em placa. O delineamento utilizado nos experimentos foi o de blocos casualizados, com cinco tratamentos (tipos de enxertia). O experimento com tamarindeiro foi constituído por sete repetições, sendo cada parcela composta por 14 mudas, num total de 98 por tratamento, perfazendo 490 no experimento. Foram avaliadas as variáveis: percentagem de pegamento dos enxertos, comprimento da parte aérea, comprimento do sistema radicular, comprimento de ramos, número de folhas, número de ramos, diâmetro do colo, matéria seca da parte aérea, matéria seca do sistema radicular, matéria seca total. Os dados obtidos foram submetidos à analise de variância e comparados através do teste de Tukey ao nível de 5% de significância utilizando o software SISVAR. Os índices de pegamento dos enxertos foram submetidos à transformação angular do arcsen &#8730;x/100, e os dados de número de ramos em &#8730;x + 0,5. Para fins da realização da estatística, o tratamento de borbulha em placa foi desconsiderado, tendo em vista que este tratamento apresentou índice zero de pegamento. Os métodos garfagem no topo em fenda cheia, garfagem no topo à inglesa complicada e garfagem no topo à inglesa simples são, respectivamente, os melhores métodos de enxertia para o tamarindeiro. O ensaio com pitombeira foi realizado com quatro repetições sendo cada parcela composta por vinte mudas, num total de 400 mudas no experimento, no qual foi verificado índice zero de pegamento dos enxertos
APA, Harvard, Vancouver, ISO, and other styles
10

Lessa, Bruno FranÃa da Trindade. "Germination and growth of seedling of Enterolobium contorsiliquum (Vell.) Morong depending on the weight of seed, location in fruit and conditions of temperature and light." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9430.

Full text
Abstract:
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico<br>Currently comes increasing the interest with agronomical emphasis by native forest species from Brazil, due its applications in various sectors of the economy. The âtamborilâ (Enterolobium contorsiliquum (Vell.) Morong) is one of these species, presenting importance for the timber, landscape, medical, beekeeping sector, beyond to be indicated for recovery of degraded large areas. The objective of this work was studying the seeds germination and seedlings growth of E. contorsiliquum in function of seeds weight, location on fruit and conditions of temperature and light. Two experiments were conducted: in the first, the seeds were separated according to the weight, in three classes (light, intermediaries and heavy), submitting each class to germination test under absence and presence of light in four different temperatures (20, 30, 40 and 20-30ÂC). This experiment was disposed in triple factorial squeme 3x2x4 (related to three classes, two light regimes and four temperatures) under completely randomized design, with four replications. In the second, the seeds were separated according to their location in the fruit (proximal, central and distal regions) and submitted to germination test under the temperatures of 25 and 20-30ÂC, using factorial squeme 3x2 (three locations and two temperatures) in completely randomized design with four replications. For both experiments were determined the variables: germination first count, final percentage and rate, length and dry weight of shoot, root and total, beyond of accelerated aging only for the second experiment. All data were submitted to normality test and, when they were presented normal was performed variance analysis and the compare means by Tukey test, when no normal only Mann-Whitney test. The germination of âtamborilâ was shown to be insensitive to light with high percentage and rate when using the temperature of 40ÂC, however this temperature detracted the seedlings development. So the temperature more indicated for the settlement of âtamborilâ is 30ÂC. The heavy seeds had always the best results, showing the use of these seeds ensures seedlings production more uniform and with good development. Among the variables assessed the location of the seeds influenced only the germination rate, which was higher for seeds of the distal region of the fruit at 25ÂC. Conclude also the alternating temperature doesnât affect the seeds germination and seedlings growth of âtamborilâ.<br>Atualmente vem crescendo o interesse com cunho agronÃmico pelas espÃcies florestais nativas do Brasil, em virtude de suas aplicaÃÃes em diversos setores da economia. O tamboril (Enterolobium contorsiliquum (Vell.) Morong) à uma destas espÃcies, apresentando importÃncia para o setor madeireiro, paisagÃstico, medicinal, melÃfero, alÃm de ser indicada para recomposiÃÃo de Ãreas degradadas. O objetivo deste trabalho foi estudar a germinaÃÃo de sementes e o crescimento de plÃntulas de tamboril em funÃÃo do peso, localizaÃÃo das sementes no fruto e condiÃÃes de temperatura e luz. Foram realizados dois experimentos: no primeiro, as sementes foram separadas de acordo com o peso, em trÃs classes (leves, mÃdias e pesadas), submetendo-se, cada classe, ao teste de germinaÃÃo sob ausÃncia e presenÃa de luz em quatro diferentes temperaturas (20, 30, 40 e 20-30ÂC). Este experimento foi disposto em esquema fatorial triplo 3x2x4 (referentes a trÃs classes, dois regimes de luz e quatro temperaturas) sob delineamento inteiramente casualisado, com quatro repetiÃÃes. No segundo, as sementes foram separadas de acordo com sua localizaÃÃo no fruto (regiÃes proximal, central e distal) e submetidas ao teste de germinaÃÃo sob as temperaturas de 25 e 20-30ÂC, utilizando-se esquema fatorial 3x2 (trÃs locais e duas temperaturas) em delineamento inteiramente casualisado com quatro repetiÃÃes. Para ambos os experimentos foram determinadas as variÃveis: primeira contagem, porcentagem final e Ãndice de velocidade de germinaÃÃo, comprimento e massa seca da parte aÃrea, raiz e total das plÃntulas, alÃm do envelhecimento acelerado para o segundo experimento. Todos os dados foram submetidos a teste de normalidade e, quando estes apresentaram-se normais realizou-se anÃlise de variÃncia e a comparaÃÃo das mÃdias pelo teste de Tukey, quando nÃo normais apenas teste de Mann-Whitney. A germinaÃÃo de tamboril mostrou-se insensÃvel à luz com alta porcentagem e velocidade quando utilizou-se a temperatura de 40ÂC, todavia esta temperatura prejudicou o desenvolvimento das plÃntulas. Assim a temperatura mais indicada para o estabelecimento de tamboril à a de 30ÂC. As sementes pesadas obtiveram sempre os melhores resultados, mostrando que a utilizaÃÃo destas sementes garante produÃÃo de mudas mais uniforme e com bom desenvolvimento. Dentre as variÃveis avaliadas, a localizaÃÃo das sementes influenciou apenas a velocidade de germinaÃÃo, a qual foi maior para as sementes da regiÃo distal do fruto a 25ÂC. Conclui-se tambÃm que a alternÃncia de temperatura nÃo afeta a germinaÃÃo e crescimento das plÃntulas de tamboril.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Seedling quality"

1

Bob, Gordon. Orchid seedling care: With special emphasis on water quality. Laid-Back Publications, 1991.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ruehle, John L. Lateral root morphology: A potential indicator of seedling quality in northern red oak. U.S. Dept. of Agriculture, Forest Service, Southeastern Forest Experiment Station, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Ruehle, John L. Lateral root morphology: A potential indicator of seedling quality in northern red oak. U.S. Dept. of Agriculture, Forest Service, Southeastern Forest Experiment Station, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

L, Duryea Mary, ed. Evaluating seedling quality: Principles, procedures, and predictive abilities of major tests : proceedings of the workshop held October 16-18, 1984. Forest Research Laboratory, Oregon State University, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Messier, Christian. Factors limiting coniferous seedling growth in recently clearcut sites dominated by Gaultheria shallon in the CWHvm subzone. Forestry Canada, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Smith, R. B. Impacts of skidroads on properties of a calcareous, loamy soil and on planted seedling performance. Pacific Forestry Centre, 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

B, Smith R. Impacts of a stump uprooting operation on properties of a calcareous loamy soil and on planted seedling performance. Pacific Forestry Centre, 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Production, of Quality 'Bramley's Seedling' Fruit Conference (2007 Armagh Ireland). The Production of Quality 'Bramley's Seedling' Fruit Conference: Wednesday 31 January 2007 at 6:30 p.m., Armagh City Hotel, Armagh. Dept. of Agriculture and Rural Development, 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Senyk, J. P. Ground-based wet weather yarding operations in coastal British Columbia: Effects on soil properties and seedling growth. Pacific Forestry Centre, 1997.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Wass, E. F. Impacts of cross-contour skidroads on properties of a gravelly sandy loam soil and on seedling performance. Pacific Forestry Centre, 1997.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Seedling quality"

1

Johnson, Jon D., and Michael L. Cline. "Seedling Quality of Southern Pines." In Forest Regeneration Manual. Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3800-0_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Sikder, Ripon Kumar, Ashok Kumar Biswas, Md Asif Iqbal, and Md Mamunur Reza. "Seed Germination and Seedling Development in Vegetable Crops." In Growth Regulation and Quality Improvement of Vegetable Crops. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-96-0169-1_2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Basu, Sudipta, and Steven P. C. Groot. "Seed Vigour and Invigoration." In Seed Science and Technology. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-5888-5_4.

Full text
Abstract:
AbstractSeed vigour is an important aspect of seed quality. It is a quantitative trait which is responsible for overall seed performance in terms of rate and uniformity of seed germination, seedling growth, emergence ability under unfavourable environments and post storage performance. Seed vigour is controlled by genetic factors, initial seed quality, production environments, harvesting and storage conditions. Seed vigour tests provide a more sensitive index of seed performance per se than the germination test. Efforts have been focused on developing novel or improving existing methods of vigour estimation in different crops. The vigour tests are tools routinely used for in-house seed quality control programs, especially for field and vegetable crops. Some treatments can improve seed vigour, although the treatment effects are more evident under sub-optimum than optimum growing conditions. This chapter deals with different aspects of seed vigour and its effects on plant growth and discusses physiological and biochemical parameters to understand underlying mechanisms.
APA, Harvard, Vancouver, ISO, and other styles
4

Lantican, Gaudencia A. "Field Screening of Gamma-Irradiated Cavendish Bananas." In Efficient Screening Techniques to Identify Mutants with TR4 Resistance in Banana. Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-662-64915-2_7.

Full text
Abstract:
AbstractIn our search for Cavendish bananas to withstand Fusarium oxysporum f. sp. cubense (Foc TR4) and other diseases, field screening of tissue-cultured Grand Nain banana seedlings derived from gamma-irradiated shoot tips was explored. Six months after irradiation and multiplication in the laboratory, the plantlets (M1V6) were individually grown in seedling bags under screen house conditions for 8 weeks, side-by-side with non-irradiated plantlets of the same clone. Once acclimatized, the banana plants were grown in an area confirmed positive of Foc TR4 (based on previous farm records stating that more than 50% of the plant population succumbed to the disease). Seedlings from each treatment (dose of radiation) were divided into four replicates, regardless of the number of plants. Each plant was given a unique identification code for traceability during disease monitoring, bunch and fruit quality evaluation.Incidences of Foc TR4, Moko disease (Ralstonia solanacearum) and virus diseases were monitored weekly. Plants found positive of any disease were eradicated immediately. The plant population for the succeeding generation was managed by removing the unwanted suckers, 12 weeks from planting using a spade gouge and keeping only one sucker per plant for the next generation. Agronomic characters of each plant were taken at the flowering stage. These included age to flower, height, pseudostem circumference, number of leaves and height of the sucker. The bunch was harvested 12 weeks from flowering. The number of hands in a bunch, the number of fingers and weight of a hand were recorded. The same agronomic characters of the plant were taken for the succeeding generations.Plants left standing in the field without any disease symptoms 3 years after planting were considered as putative mutants and were selected as candidate lines for multiplication and second-generation field screening. Only healthy suckers (free from viruses) were further multiplied via tissue culture technique to reach M1V6. Clean suckers from each line free of soil debris or dirt were sent to the laboratory for multiplication. At least 1000 plantlets were produced from each line for the second-generation field screening. These were grown in two locations – with and without records of Foc TR4. Field monitoring activities including plant population management, disease incidence assessment and fruit quality evaluation were carried out following the same protocols used in the establishment of the first-generation plants. Lines with population showing ≤10% Foc TR4 after the first harvest, with good vigor, fruit quality and productivity were considered as candidates for further multiplication, farmers distribution and field planting under semi-commercial scale.
APA, Harvard, Vancouver, ISO, and other styles
5

Geras'kin, Stanislav, Roman Churyukin, Polina Volkova, and Sofiya Bitarishvili. "Using ionizing radiation for improving the development and yield of agricultural crops." In Mutation breeding, genetic diversity and crop adaptation to climate change. CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0043.

Full text
Abstract:
Abstract The response of barley seedlings was studied after gamma irradiation of seeds with doses in the range of 2-50 Gy. It was shown that stimulation of plant growth occurred in the dose range of 16-20 Gy. The influences of the dose rate, the quality of seeds and their moisture on the manifestation of radiation effects were investigated. We studied, under controlled conditions, the activities of metabolic and antioxidant enzymes and observed an increase in their activity in the range of doses that cause stimulation of seedling growth. We showed that changes in the balance among different classes of phytohormones were probably involved in the acceleration of plant growth after irradiation of seeds using stimulating doses. Gamma irradiation of barley seeds significantly influenced the development of plants during the growing season. After irradiation with stimulating doses, we observed a reduction in the duration of the initial stages of ontogenesis; the phase of full ripeness occurred 5-7 days earlier than in the controls. The manifestation of the effect of irradiation depended on the conditions in which the plants developed. During the growing season of 2014, which was a dry year, plants originating from the irradiated seeds showed an increase in the number of productive stems, which led to an increase in yield by 34-38%; during the optimal 2015 season, an increase in the number of grains per spike caused an increase in yield by 8-29%. Therefore, our field study has shown that at least some hormetic effects can occur in the field. Irradiation of seeds can increase field germination, stimulate the growth and development of plants and increase their resistance to unfavourable environmental conditions. A more complete understanding of the underlying mechanisms of hormesis is needed to exploit its potential benefits in crop production.
APA, Harvard, Vancouver, ISO, and other styles
6

Nautiyal, P. C., K. Sivasubramaniam, and Malavika Dadlani. "Seed Dormancy and Regulation of Germination." In Seed Science and Technology. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-5888-5_3.

Full text
Abstract:
AbstractSeed germination and dormancy are vital components of seed quality; hence, understanding these processes is essential for a sound seed production system. The two processes are closely interrelated and regulated, both by genetic as well as environmental factors. While dormancy provides an inherent mechanism aimed at the survival of the plant species to withstand adverse external conditions by restricting the mature seed from germinating, the ability of the dehydrated seed to remain viable and produce a vigorous seedling upon hydration under favourable conditions is the key to the survival and perpetuation of the plant species. In addition, quality seed is expected to result in timely and uniform germination under favourable field conditions after sowing to establish a healthy crop stand. Therefore, in seed technology, dormancy is not considered a desirable trait in the seed lots used for sowing. Thus, to achieve the highest germination percentage, understanding the factors controlling these two interlinked and contrasting processes is vital. In seed testing and seed trade, knowledge of seed germination and dormancy is needed for a reliable assessment of seed quality and its planting value, and to make right decisions. Though much is yet to be understood, the present status of knowledge on these aspects has made significant advances, especially in genetic control, molecular mechanism, and physiological and environmental factors influencing germination and dormancy. The information compiled in this chapter may help the seed technologists in developing new methods for breaking dormancy and testing germination,
APA, Harvard, Vancouver, ISO, and other styles
7

Saravanan, T. S., K. Rajendran, M. Uma, and P. Chezhian. "Effects of Bioinoculants on Quality Seedling Production and Nutrient Uptake of Casuarina equisetifolia Forst. Grown in Decomposed Coir Pith." In Microbiological Research In Agroecosystem Management. Springer India, 2013. http://dx.doi.org/10.1007/978-81-322-1087-0_10.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Das, Priyanka, Rajeev N. Bahuguna, Rohit Joshi, Sneh Lata Singla-Pareek, and Ashwani Pareek. "In search of mutants for gene discovery and functional genomics for multiple stress tolerance in rice." In Mutation breeding, genetic diversity and crop adaptation to climate change. CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0045.

Full text
Abstract:
Abstract Mutation breeding is a commanding tool, which has been adapted to generate altered genetic material to study functional genomics, including understanding the molecular basis of stress tolerance. Hitherto, several rice lines have been generated through mutagenesis and the mutated genes responsible for the 'gain of function' in terms of plant architecture, stress tolerance, disease resistance and grain quality have been characterized. Oryza sativa L. cv. IR64 is a high-yielding rice cultivar but sensitive to abiotic stresses such as acute temperatures, salinity and drought. In this study, a population of rice IR64 mutants was generated using gamma irradiation. The population was then subjected to a preliminary phenotypic screening under abiotic stresses such as heat and salinity at the seedling stage. On the basis of root length, shoot length, fresh weight, dry weight and chlorophyll measurements, we identified eight 'gain-of-function' mutant lines and used them for further biochemical and molecular characterization. Phenotyping results demonstrated that the identified mutant plants have gained the potential to thrive under heat and salinity conditions. This information would be of wide scientific interest and helpful for developing novel cultivars able to maintain yield in saline, hot and dry areas.
APA, Harvard, Vancouver, ISO, and other styles
9

Takoutsing, B., A. Degrande, Z. Tchoundjeu, E. Asaah, and A. Tsobeng. "Improving the Availability of Quality Planting Materials Through Community-Based Seed and Seedling Systems: The Case of Rural Resource Centres in Cameroon." In Challenges and Opportunities for Agricultural Intensification of the Humid Highland Systems of Sub-Saharan Africa. Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-07662-1_24.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Gomez-Pando, Luz, Jesus Bernardo-Rojas, Denisse Deza-Montoya, Martha Ibañez-Tremolada, and Enrique Aguilar-Castellanos. "Mutation induction to improve quinoa (Chenopodium quinoa) resistance to downy mildew (Peronospora variabilis)." In Mutation breeding, genetic diversity and crop adaptation to climate change. CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0019.

Full text
Abstract:
Abstract Quinoa is an important crop due to its nutritional characteristics (better than cereals) and its tolerance to abiotic stresses. However, various factors such as high susceptibility to diseases, especially downy mildew caused by Peronospora variabilis, limit its agricultural performance. Genetic improvement of quinoa could reduce the need to use fungicides for this crop and maintain the organic quality of Peruvian production in small-scale farms. Seeds of var. 'Amarilla Marangani', irradiated with 150 and 250 Gy of gamma-rays (<sup>60</sup>Co), were evaluated in two experimental locations in Peru: coastland at La Molina and highland at Huancayo. Resistance to downy mildew and other agricultural traits in the M<sub>3</sub> and M<sub>4</sub> generations was studied. In both locations, downy mildew was observed in susceptible plants under natural infection, from the seedling stage to plant maturity. At the coastland site, six mutants with 30% leaf infection were obtained in the progeny of plants exposed to 150 Gy. Five additional mutants with 40% leaf infection were found in the progeny of plants exposed to 250 Gy. In the highland trial, only seven lines were identified with 30% severity (foliar area with symptoms) among the plants from the 150 Gy experiment. The parent materials showed 70-80% disease severity. Mutant lines with quantitative resistance and tolerance to downy mildew, high yield potential, reduced duration, shorter plant height, altered inflorescence shape and grain colour mutations were selected from both doses. This study showed that quantitative resistance and tolerance to downy mildew could be obtained in quinoa and this resulted in increased grain yields.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Seedling quality"

1

DUMINS, Karlis, Toms STALS, and Dagnija LAZDINA. "FOREST REGENERATION QUALITY ASSESSMENT BY ASTA SYSTEM." In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.178.

Full text
Abstract:
In Latvia one third of the total forest area is regenerated by planting tree seedlings and therefore it is important to choose the appropriate soil preparation method and the right type of regeneration material for each forest type. Usually the success of afforestation is evaluated by how high is the average seedling survival rate and growth parameters like height, annual increment, diameter at breast height while the location of the seedling is disregarded. This may be of great importance since in such stands the environmental conditions typically are not entirely homogenous. Micro topography differences impact seedling growth, because it modifies water regime, temperature, micronutrient availability, sun radiation and other factors. Therefore, aim of this work is to improve monitoring methods and determine the most efficient soil preparation and seedling preparation combination to improve the quality of forest regeneration. That could be done using ASTA documentation system originally developed to show seedling and mound location and density in planting area during mechanic planting. But it also allows to link the precise location of the seedling and growing conditions with its growing rate and survival and therefore it is easier to exclude seedlings that are affected by other factors than those that you are interested in, so you can gain more representative results. This also could be used in forest management. When using ASTA system it is also possible to display how different tree disease are distributed in the stand, if they have spread eventually or localized only in some parts of the stand, also it can be used for browsing and other tree damage monitoring in the stand. In conclusion: in harsh environmental conditions on unprepared forest soil and soil prepared in furrows made by disc trench larger seedlings show better survival rate. Survival of seedlings is significantly impacted by micro topography, whereas mounded micro sites equalize local environmental conditions that reduce impact of micro topography.
APA, Harvard, Vancouver, ISO, and other styles
2

Pavlović, Nenad, Vladimir Crepuljarević, Jelena Mladenović, et al. "INFLUENCE OF DIFFERENT SUBSTRATES ON THE QUALITY OF PEPPER SEEDLINGS (Capsicum annuum L.)." In 2nd International Symposium on Biotechnology. Faculty of Agronomy in Čačak, University of Kragujevac, 2024. http://dx.doi.org/10.46793/sbt29.12np.

Full text
Abstract:
The paper shows the influence of different substrates on the quality of pepper seedlings. Based on the obtained results, it can be concluded that different substrates had an impact on the biological-morphological characteristics of pepper seedlings. The best results for most of the analyzed biological-morphological characteristics of pepper seedlings, according to the results obtained by the experiment, are related to the substrates “Glistenjak“, „K-Potgrond H-Black 90%“ and “K-TS1-White 100%”, while the worst results were achieved on the examined substrates of “Coconut Cube”. The mean value for all traits was recorded on the substrate “K- Seedling substrat”.
APA, Harvard, Vancouver, ISO, and other styles
3

Tyutyunnikova, E. M., M. A. Sanin, and T. V. Plotnikova. "THE EFFECT OF BIOREGULATOR REGOPLANT ON TOBACCO PRODUCTIVITY DURING THE SEEDING AND FIELD PERIODS." In 11-я Всероссийская конференция молодых учёных и специалистов «Актуальные вопросы биологии, селекции, технологии возделывания и переработки сельскохозяйственных культур». V.S. Pustovoit All-Russian Research Institute of Oil Crops, 2021. http://dx.doi.org/10.25230/conf11-2021-249-254.

Full text
Abstract:
We studied the effect of the growth regulator Regoplant on the mass of seedlings, the quality of seedlings and the productivity of tobacco. Soaking tobacco seeds before sowing in a 0.0001 % solution of the preparation at an exposure of 6 hours, and then spraying the plants at the stage of “auricles” and “seedling ready for planting” with a working solution of an agrochemical with a 0.00001 % concentration significantly improved the quality of seedlings. This technique increases the length of tobacco seedlings to the apical point by 66 %, to the end of elongated leaves by 29 %, the mass of stems by 53 %, the mass of roots by 32 %, the diameter of the stem by 38 %. After planting the plants in the field, developed under the influence of the Regoplant stimulator, we noted an increase in productivity by 16 % and an improvement in the quality of raw materials due to an increase in carbohydrates and a decrease in proteins. The economic effect against the background of the application of Regoplant preparation amounted to 106 thousand rubles.
APA, Harvard, Vancouver, ISO, and other styles
4

Baldota, Soumil, Rajdeep Porua, Vadivu G, and Pao-Ann Hsiung. "Improving Seedling Quality and Predict Plant Growth Using Convolutional Neural Networks ICRTDA-157." In International Conference on Recent Trends in Data Science and its Applications (ICRTDA 2023). River Publishers, 2023. http://dx.doi.org/10.13052/rp-9788770040723.035.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

"Plant Growth-Promoting Rhizobacteria Improved Seedling Growth and Quality of Cucumber (Cucumis sativus L.)." In International Conference on Chemical, Food and Environment Engineering. International Academy Of Arts, Science & Technology, 2015. http://dx.doi.org/10.17758/iaast.a0115068.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Luković, Kristina, Nenad Đurić, Ivan Tupajić, et al. "ARTIFICIAL LIGHTING AS AN EFFECTIVE METHOD FOR INCREASING LETTUCE SEEDLING DEVELOPMENT." In 3rd International Symposium on Biotechnology. University of Kragujevac, Faculty of Agronomy in Čačak, 2025. https://doi.org/10.46793/sbt30.14kl.

Full text
Abstract:
Due to the short duration of sunlight and low light intensity during the winter, the lettuce photosynthesis is limited, resulting in slow growth and reduced quality. This study aimed to investigate the effects of light- emmiting diodes (LEDs) on the growth and quality of three lettuce cultivar seedlings. Results of our research indicate that applied light treatments significantly influenced the growth and development of all three lettuce cultivar seedlings. The highest shoot and root weight was achieved in the Jukebox cultivar grown under blue LEDs, while the highest total chlorophyll and carotenoid content was achieved in the Viola cultivar grown under white and blue LEDs, respectively.
APA, Harvard, Vancouver, ISO, and other styles
7

Luković, Kristina, Aleksandra Rakonjac, Vladimir Perišić, Kristina Markeljić, and Slađan Adžić. "THE INFLUENCE OF ARTIFICIAL ILLUMINATION AND TILLAGE TREATMENTS ON ENHANCING LETTUCE GROWTH AND QUALITY." In 3rd International Symposium on Biotechnology. University of Kragujevac, Faculty of Agronomy in Čačak, 2025. https://doi.org/10.46793/sbt30.16kl.

Full text
Abstract:
Lettuce (Lactuca sativa L.) indoor cultivation during the winter is mainly influenced by low light intensities. Also, its production is significantly affected by tillage techniques. Therefore, our research aimed to investigate the impact of applied light treatments during the seedling stage and applied tillage treatments after plant transplanting on the Viola lettuce genotype. Applied light and tillage treatments significantly influenced shoot weight, while the root weight and the total chlorophyll content varied depending on the light treatment. Tillage treatment did not affect shoot weight and the total chlorophyll content, but significantly influenced soluble sugar content.
APA, Harvard, Vancouver, ISO, and other styles
8

Flores, Andrés, Tomás Pineda, Eulogio Flores, Enrique Buendía, Vidal Guerra, and Fabián Islas. "Seedling quality from six <em>Pinus</em> species produced in polyethylene bag." In The 1st International Electronic Conference on Forests — Forests for a Better Future: Sustainability, Innovation, Interdisciplinarity. MDPI, 2020. http://dx.doi.org/10.3390/iecf2020-08106.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Tiutiunnikova, E. M., and T. V. Plotnikova. "Influence of humic fertilizer Lignohumate on the sowing properties of seeds, seedling quality and tobacco yield." In Scientific achievements of the third millennium. SPC "LJournal", 2018. http://dx.doi.org/10.18411/scc-09-2018-12.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

S., Erick Fiestas, Paulo Linares O., Jorge Alva A., and Sixto Prado G. "Integration of an IIoT Platform with A Deep Learning Based Computer Vision System for Seedling Quality Control Automation." In 2021 IEEE 3rd Eurasia Conference on IOT, Communication and Engineering (ECICE). IEEE, 2021. http://dx.doi.org/10.1109/ecice52819.2021.9645700.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Seedling quality"

1

Israel, Alvaro, and John Merrill. Production of Seed Stocks for Sustainable Tank Cultivation of the Red Edible Seaweed Porphyra. United States Department of Agriculture, 2006. http://dx.doi.org/10.32747/2006.7696527.bard.

Full text
Abstract:
Porphyra species (commonly known as ‘nori’ or ‘purple laver’) are edible red seaweeds rich in proteins, vitamins and other highly valued biogenic compounds. For years Porphyra has been cultured using seeded nets extended in the open sea, and its biomass consumed primarily in the Far East. While demands for international markets have increased steadily at an average of 20% per year, supplies are on the verge and not expected to meet future demands. Alternatively, land-based cultivation of seaweed has become attractive in the mariculture industry since (1) important growth parameters can be controlled, (2) is environmentally friendly and (3) perfectly matches with integrated aquaculture leading to sustainable, high quality products. During the last few years a tank cultivation technology for Porphyra has been developed at the Israeli institution. This technology is based on indoor production of asexual spores and their subsequent growth to 1-2 mm seedlings. The seedlings are then transferred to outdoor tanks and ponds when seawater temperatures drop to 20 °C, or below, and days become shorter during winter time. However, the current technology efficiently serves only about 100 m2 of ponds during one growth season. In order to produce seedlings in sufficient amounts, it is critical to address both technical and biological aspects of seedling production, securing optimal up-scale to commercial-size cultivation farms. We hypothesize that massive production of spores is related to thalli origin, thalli age and sporulation triggers, and that seedling survival and their subsequent growth potential is determined by the seawater quality and overall indoor growth conditions imposed. A series of bio-reactors were constructed and tested in which spore release and spore growth were separately studied. The main assessment criteria for optimal viability of the seedlings will be by determining their electron transport rate using PAM fluorometry and by subsequent growth and biomass yields in outdoor ponds. Altogether the project showed (1), controlled sporulation is possible in big outdoor/growth chamber settings provided initial stock material (small frozen seedlings) is at hand, (2), contamination problems can be almost completely avoided if stock material is properly handled (clean as possible and partially dehydrated prior to freezing), (3), spore release can significantly be enhance using high nutrient levels during thawing for P. yezoensis and P. haitanensis, but not for P. rosengurttii, (4), PAM fluorometry is an efficient tool to estimate growth capacity in both seedlings and juvenile thalli. The BARD funding also served to explore other aspects of Porphyra biology and cultivation. For example, the taxonomical status of Porphyra strains used in this study was defined (see appendix), and the potential use of this seaweed in bioremediation was well substantiated. In addition, BARD funding supported a number of opportunities and activities in the Israeli lab, direct or indirectly related to the initial objectives of the project such as: additional molecular work in other seaweeds, description of at least 2 new species for the Israeli Mediterranean, and continuous support for the writing of a book on Global Change and applied aspects of seaweeds. The technology for Porphyra cultivation in land-based ponds is readily available. This study corroborated previous know-how of Porphyra growth in tanks and ponds, and yet offers important improvements regarding seedling production and their handling for successful cultivation. This study supported various other activities opening additional important issues in the biology/cultivation/use of Porphyra and other seaweeds.
APA, Harvard, Vancouver, ISO, and other styles
2

Sadka, Avi, Mikeal L. Roose, and Yair Erner. Molecular Genetic Analysis of Citric Acid Accumulation in Citrus Fruit. United States Department of Agriculture, 2001. http://dx.doi.org/10.32747/2001.7573071.bard.

Full text
Abstract:
The acid content of the juice sac cells is a major determinant of maturity and fruit quality in citrus. Many citrus varieties accumulate acid in concentrations that exceed market desires, reducing grower income and consumer satisfaction. Pulp acidity is thought to be dependent on two mechanisms: the accumulation of citric acid in the vacuoles of the juice sac cells, and acidification of the vacuole. The major aim of the project was to direct effort toward understanding the mechanism of citric acid accumulation in the fruit. The following objectives were suggested: Measure the activity of enzymes likely to be involved in acid accumulation and follow their pattern of expression in developing fruit (Sadka, Erner). Identify and clone genes which are associated with high and low acid phenotypes and with elevated acid level (Roose, Sadka, Erner). Convert RAPD markers that map near a gene that causes low acid phenotype to specific co dominant markers (Roose). Use genetic co segregation to test whether specific gene products are responsible for low acid phenotype (Roose and Sadka). Objective 1 was fully achieved. Most of the enzymes of organic acid metabolism were cloned from lemon pulp. Their expression was studied during fruit development in low and high acid varieties. The activity and expression of citrate synthase, aconitase and NADP-isocitrate dehydrogenase (IDH) were studied in detail. The role that each enzyme plays in acid accumulation and decline was evaluated. As a result, a better understanding of the metabolic changes that contribute to acid accumulation was achieved. It was found that the activity of the mitochondrial aconitase is greatly reduced early in high-acid fruits, but not in acidless ones, suggesting that this enzyme plays an important role in acid accumulation. In addition, it was demonstrated that increases in the cytosolic forms of aconitase and NADP-IDH towards fruit maturation play probably a major role in acid decline. Our studies also demonstrated that the two mechanisms that contribute to fruit acidity, vacuolar acidification and citric acid accumulation, are independent, although they are tightly co-regulated. Additional, we demonstrated that sodium arsenite, which reduce fruit acidity, causes a transient inhibition in the activity of citrate synthase, but an induction in the gene expression. This part of the work has resulted in 4 papers. Objective 3 was also fully achieved. Using bulked segregant analysis, three random amplified polymorphic DNA (RAPD) markers were identified as linked to acitric, a gene controlling the acidless phenotype of pummelo 2240. One of them, which mapped 1.2 cM from acitric was converted into sequence characterized amplified region (SCAR marker, and into co dominant restriction length polymorphism (RFLP) marker. These markers were highly polymorphic among 59 citrus accessions, and therefore, they should be useful for selecting seedling progeny heterozygous for acitric in nearly all crosses between pummelo 2240 and other citrus genotypes. This part of the project resulted in one paper. Objective 4 was also fully achieved. Clones isolated by the Israeli group were sent to the American laboratory for co segregation analysis. However, none of them seemed to co segregate with the low acid phenotype. Both laboratories invested much effort in achieving the goals of Objective 2, namely the isolation of genes that are elevated in expression in low and high acid phenotypes, and in tissue cultures treated with arsenite (a treatment which reduces fruit acidity). However, conventional differential display and restriction fragment differential display analyses could not identify any differentially expressed genes. The isolation of such genes was the major aim of a continuation project, which was recently submitted.
APA, Harvard, Vancouver, ISO, and other styles
3

Sanders, Suzanne, Jessica Kirschbaum, Suzanne Sanders, and Jessica Kirschbaum. Forest vegetation monitoring protocol (version 2.1): Great Lakes Inventory and Monitoring Network. National Park Service, 2024. http://dx.doi.org/10.36967/2305281.

Full text
Abstract:
Forest vegetation provides an integrated measure of terrestrial ecosystem health by expressing information about the collective suite of drivers and stressors which act upon it. These include climate, disturbance, browse, and invasive species. We developed a comprehensive forest monitoring protocol to detect change in the nine Great Lakes Network parks. Monitoring is conducted on a nine-year rotation, with each of the parks sampled over the course of one summer, once every nine years. Site locations were selected to ensure that they are random, but also spatially balanced throughout the parks. At each sampling site, we collect extensive data on trees (including saplings and seedlings), shrubs, herbs, coarse woody material, and browse. We also carry out assessments of tree health. Data are housed in a Microsoft Access database, and appropriate metadata are generated annually. Quality control measures include both on site assessments of accuracy, as well as extensive data checking via automated parsing routines. Finally, reports from monitoring are produced on a regular basis and include internal National Park Service technical reports and externally reviewed manuscripts for publication in peer-reviewed journals. All data are publicly available.
APA, Harvard, Vancouver, ISO, and other styles
4

Leis, Sherry. Vegetation community monitoring trends in restored tallgrass prairie at Wilson’s Creek National Battlefield: 2008–2020. National Park Service, 2022. http://dx.doi.org/10.36967/nrr-2293117.

Full text
Abstract:
Plant community monitoring at Wilson’s Creek National Battlefield (NB) focused on the restored tallgrass prairie community. Six monitoring sites were visited four times and observations of plant species and ground cover were made. In addition to those observations, we included two environmental factors in this report—precipitation and recent fire history—to help understand the vegetation data status and trends. Precipitation data (standardized vegetation index) indicated drought conditions in 2012 and some dry periods in 2016. Although prairies are adapted to drought, we found that species richness at the site and community scales (alpha and gamma diversity) were reduced in dry years. Fire management also plays an important role in shaping the plant communities. Prescribed fire occurrence became less frequent through the monitoring period. Also, additional treatments, including herbicide and mowing, likely shaped the prairie community. Tree regeneration and nonnative plants in particular may have been affected by these techniques. The prairie plant community continues to be moderately diverse despite recent increases in tree seedlings and small saplings. Species richness varied over time and was correlated with precipitation; diversity indices (H′ and J′) were similar across monitored years. Species guilds (also known as functional groups) demonstrated differing patterns. Woody plants, long a concern at the park, were abundant and statistically similar across years. Many guilds were quite variable across the sites, but nonnative forbs declined, and nonnative grasses increased. Overstory trees and canopy cover, measured for the first time in 2020, have likely influenced the composition of one site. The composition of this site points to a shrubland-savanna community. Four of the sites tended towards shrubland rather than tallgrass prairie. The vegetation monitoring protocol experienced some changes between 2008 and 2020. A key difference was a shift from sampling twice during the field season to sampling only once in a monitoring year. An anticipated decline in species richness was observed in 2012 and 2016, but we were unable to isolate sample design as the cause. Additionally, we remedied inconsistencies in how tree regeneration was recorded by tallying seedlings and saplings in the field. Our quality assurance procedures indicated that our observer error from pseudoturnover was 20.2%, meeting our expectations. Cover class estimates agreed 73% of the time, with all disagreements within one cover class. Coordinating management actions to achieve plant community goals like structure and composition of tallgrass prairie will be critical to the survival of the prairie species at the park. Fire and nonnative plant treatments along with the reduction of woody cover including trees are needed to arrest the transition to savanna and woodland community types. Frequent prescribed fire is an integral process for this community and there is no equivalent substitute. Continued focus on management for the desired tallgrass prairie community will also provide needed habitat for imperiled pollinators such as the monarch butterfly. Best management practices for pollinators on federal lands specify that treatments (prescribed fire, mowing or haying) should not occur during the blooming season or when pollinator breeding, egg, larval or pupal stages are present.
APA, Harvard, Vancouver, ISO, and other styles
5

Wagner, D. Ry, Eliezer Lifschitz, and Steve A. Kay. Molecular Genetic Analysis of Flowering in Arabidopsis and Tomato. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7585198.bard.

Full text
Abstract:
The primary objectives for the US lab included: the characterization of ELF3 transcription and translation; the creation and characterization of various transgenic lines that misexpress ELF3; defining genetic pathways related to ELF3 function regulating floral initiation in Arabidopsis; and the identification of genes that either interact with or are regulated by ELF3. Light quality, photoperiod, and temperature often act as important and, for some species, essential environmental cues for the initiation of flowering. However, there is relatively little information on the molecular mechanisms that directly regulate the developmental pathway from the reception of the inductive light signals to the onset of flowering and the initiation of floral meristems. The ELF3 gene was identified as possibly having a role in light-mediated floral regulation since elj3 mutants not only flower early, but exhibit light-dependent circadian defects. We began investigating ELF3's role in light signalling and flowering by cloning the ELF3 gene. ELF3 is a novel gene only present in plant species; however, there is an ELF3 homolog within Arabidopsis. The Arabidopsis elj3 mutation causes arrhythmic circadian output in continuous light; however, we show conclusively normal circadian function with no alteration of period length in elj3 mutants in dark conditions and that the light-dependent arrhythmia observed in elj3 mutants is pleiotropic on multiple outputs regardless of phase. Plants overexpressing ELF3 have an increased period length in constant light and flower late in long-days; furthermore, etiolated ELF3-overexpressing seedlings exhibit a decreased acute CAB2 response after a red light pulse, whereas the null mutant is hypersensitive to acute induction. This finding suggests that ELF3 negatively regulates light input to both the clock and its outputs. To determine whether ELF3's action is phase dependent, we examined clock resetting by light pulses and constructed phase response curves. Absence of ELF3 activity causes a significant alteration of the phase response curve during the subjective night, and overexpression of ELF3 results in decreased sensitivity to the resetting stimulus, suggesting that ELF3 antagonizes light input to the clock during the night. Indeed, the ELF3 protein interacts with the photoreceptor PHYB in the yeast two-hybrid assay and in vitro. The phase ofELF3 function correlates with its peak expression levels of transcript and protein in the subjective night. ELF3 action, therefore, represents a mechanism by which the oscillator modulates light resetting. Furthermore, flowering time is dependent upon proper expression ofELF3. Scientifically, we've made a big leap in the understanding of the circadian system and how it is coupled so tightly with light reception in terms of period length and clock resetting. Agriculturally, understanding more about the way in which the clock perceives and relays temporal information to pathways such as those involved in the floral transition can lead to increased crop yields by enabling plants to be grown in suboptimal conditions.
APA, Harvard, Vancouver, ISO, and other styles
6

Fromm, Hillel, Paul Michael Hasegawa, and Aaron Fait. Calcium-regulated Transcription Factors Mediating Carbon Metabolism in Response to Drought. United States Department of Agriculture, 2013. http://dx.doi.org/10.32747/2013.7699847.bard.

Full text
Abstract:
Original objectives: The long-term goal of the proposed research is to elucidate the transcription factors, genes and metabolic networks involved in carbon metabolism and partitioning in response to water deficit. The proposed research focuses on the GTLcalcium/calmodulinbindingTFs and the gene and metabolic networks modulated by these TFs in Arabidopsis thaliana. The specific objectives are as follows. Objective-1 (USA): Physiological analyses of GTL1 loss- and gain-of-function plants under water sufficient and drought stress conditions Objective 2 (USA / Israel-TAU): Characterizion of GTL target genes and bioinformatic analysis of data to eulcidate gene-network topology. Objective-3 (Israel-TAU): Regulation of GTLmediated transcription by Ca²⁺/calmodulin: mechanism and biological significance. Objective-4 (Israel-BGU): Metabolic networks and carbon partitioning in response to drought. Additional direction: In the course of the project we added another direction, which was reported in the 2nd annual report, to elucidate genes controlling drought avoidance. The TAU team has isolated a few unhydrotropic (hyd) mutants and are in the process of mapping these mutations (of hyd13 and hyd15; see last year's report for a description of these mutants under salt stress) in the Arabidopsis genome by map-based cloning and deep sequencing. For this purpose, each hyd mutant was crossed with a wild type plant of the Landsberg ecotype, and at the F2 stage, 500-700 seedlings showing the unhydrotropic phenotype were collected separately and pooled DNA samples were subkected to the Illumina deep sequencing technology. Bioinformatics were used to identify the exact genomic positions of the mutations (based on a comparison of the genomic sequences of the two Arabidopsis thaliana ecotypes (Columbia and Landsberg). Background: To feed the 9 billion people or more, expected to live on Earth by the mid 21st century, the production of high-quality food must increase substantially. Based on a 2009 Declaration of the World Summit on Food Security, a target of 70% more global food production by the year 2050 was marked, an unprecedented food-production growth rate. Importantly, due to the larger areas of low-yielding land globally, low-yielding environments offer the greatest opportunity for substantial increases in global food production. Nowadays, 70% of the global available water is used by agriculture, and 40% of the world food is produced from irrigated soils. Therefore, much needs to be done towards improving the efficiency of water use by plants, accompanied by increased crop yield production under water-limiting conditions. Major conclusions, solutions and achievements: We established that AtGTL1 (Arabidopsis thaliana GT-2 LIKE1) is a focal determinant in water deficit (drought) signaling and tolerance, and water use efficiency (WUE). The GTL1 transcription factor is an upstream regulator of stomatal development as a transrepressor of AtSDD1, which encodes a subtilisin protease that activates a MAP kinase pathway that negatively regulates stomatal lineage and density. GTL1 binds to the core GT3 cis-element in the SDD1 promoter and transrepresses its expression under water-sufficient conditions. GTL1 loss-of-function mutants have reduced stomatal number and transpiration, and enhanced drought tolerance and WUE. In this case, higher WUE under water sufficient conditions occurs without reduction in absolute biomass accumulation or carbon assimilation, indicating that gtl1-mediated effects on stomatal conductance and transpiration do not substantially affect CO₂ uptake. These results are proof-of-concept that fine-tuned regulation of stomatal density can result in drought tolerance and higher WUE with maintenance of yield stability. Implications: Accomplishments during the IS-4243-09R project provide unique tools for continued discovery research to enhance plant drought tolerance and WUE.
APA, Harvard, Vancouver, ISO, and other styles
7

Leis, Sherry, Lloyd Morrison, and Tani Hubbard. Long-term trends in prairie vegetation at three national parks: 1998?2022. National Park Service, 2024. http://dx.doi.org/10.36967/2302359.

Full text
Abstract:
The Heartland Inventory and Monitoring Network has monitored plant communities in National Parks since 1998. Three of those parks in the northern tier of the network?Herbert Hoover National Historic Site (NHS), Homestead National Historical Park (NHP), and Pipestone National Monument (NM)?have reconstructed tallgrass prairie communities and were sampled concurrently in 2022. In this combined report, we describe similarities and differences among the three parks related to current vegetation and trends. Climatically, Herbert Hoover NHS and Homestead NHP have similar temperature profiles, but Homestead NHP is drier. Pipestone NM differs from the other two parks in temperature and precipitation. Long-term climatic signals for major drought events varied by park, and moisture at Herbert Hoover NHS is likely to increase with climate change. Precipitation shifts could influence vegetation trends in the future requiring action such as flood mitigations, wildfire protections during prolonged drought, and consideration for species additions to adapt to new climate profiles. Plant composition was similar for Herbert Hoover NHS and Homestead NHP while the combination of plant species and abundances at Pipestone NM was different from the other two parks, especially within the Sioux Quartzite community type. There appeared to be some compositional shifts over time for Homestead NHP. That trend was supported by greater species turnover at Homestead NHP than the other two parks. The reconstruction at Homestead NHP is older than that of Herbert Hoover NHS and possibly Pipestone NM, but we are unable to determine the underlying causes of species changes. Quality assessment procedures provided a moderate level of confidence in our data with respect to botanist agreement on identifications. We met our goal of about 80% agreement in species composition. Cover class agreement was greater than?70%, with less than 4% of observations off by more than one class. Native species richness trends varied by park. Herbert Hoover NHS continues to gain native species while Pipestone NM is losing species. Species richness at Homestead NHP did not exhibit a directional trend. Pipestone NM tended to have less cover of forbs and grasses than the other two parks, reflecting the more complex geological landscape with surface rock. Grass abundance appears to be declining from baseline years for all three parks. Grass-like and fern guilds are much less abundant in all the parks than other plant guilds. Woody plants in 2022 were similar at Herbert Hoover NHS and Homestead NHP in terms of mean cover and heterogeneity across the prairies, but tree encroachment into the grasslands is a potential concern. Pipestone NM generally had fewer woody plants (including tree seedlings) in 2022, but the amount varied through time. Canopy closure, measured for the first time in 2022, was present in all three parks, but was greatest at Homestead NHP. Nonnative plant cover was the greatest at Pipestone NM, but current abundance at Herbert Hoover NHS was greater in 2022 than baseline years. Homestead NHP consistently had little nonnative plant cover since 2005. Abundance (% cover) of two nonnative grasses of concern?Kentucky bluegrass (Poa pratensis) and smooth brome (Bromus inermis)?differed by park and year. Recent increases in Kentucky bluegrass abundance at Herbert Hoover NHS might reflect changes in management. Although these parks have individual differences in climate as well as in timing and use of management actions, they share similar histories of cultivation and reconstruction. Efforts to restore or reconstruct portions of the prairie at Pipestone NM were unique among the three parks. Future analyses might continue to combine Herbert Hoover NHS and Homestead NHP but examine Pipestone NM separately; the unique geologic history and differences in vegetation communities at Pipestone NM may make individual assessment a better option. However, comparing trends in guilds of concern, such as woody and nonnative plants, across all three parks can be helpful for gauging success with management tools in light of regional changes in climate.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography