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Journal articles on the topic 'Seedling Tolerance'
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1
Cobb, B. G., D. L. Andrews, D. M. MacAlpine, J. R. Johnson, and M. C. Drew. "1001 ANOXIA TOLERANCE OF MAIZE SEEDLING ROOTS." HortScience 29, no. 5 (1994): 573a—573. http://dx.doi.org/10.21273/hortsci.29.5.573a.
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We have been examining the response of maize seedling roots to oxygen stress. Previously, we have shown that maize seedlings with primary root lengths of 10cm or greater require a pretreatment with low oxygen (hypoxia) for survival of greater than 12 hours of anoxia. During the pretreatment there is induction of mRNA and increase in enzymatic activity of alcohol dehydrogenase (ADH) and other enzymes that are necessary for alcoholic fermentation. However, we have found that younger seedlings do not need a pretreatment to survive anoxia. They appear to have high levels of ADH and other enzymes that are needed for anaerobic survival at levels equivalent to those that are induced in older seedlings. These results suggest that, at the time of seedling emergence, seedlings may be more adapted to oxygen stress than during later stages of growth.
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Xu, Yunji, Xuelian Weng, Liqiu Jiang, et al. "Screening and Evaluation of Salt-Tolerant Wheat Germplasm Based on the Main Morphological Indices at the Germination and Seedling Stages." Plants 13, no. 22 (2024): 3201. http://dx.doi.org/10.3390/plants13223201.
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The successful screening and evaluation of salt-tolerant germplasm at the germination and seedling stages is of great importance for promoting the breeding of wheat varieties with salt tolerance. In this study, 70 wheat varieties bred in different regions were evaluated for salt tolerance through hydroponic exposure to different concentrations of salt. The relative water absorption, water absorption rate, dehiscence rate, germination rate, and germination index of seeds, and plant height, root length, stem diameter, and biomass of seedlings were determined at the germination and seedling stages of wheat, and the salt tolerance was identified and evaluated using multivariate statistical analysis. The germination ability and seedling growth potential of wheat germplasms decreased with the aggravation of salt stress. Based on the comprehensive salt tolerance index at the germination stage, our study identified 35 varieties to be salt-tolerant. There were nine varieties further screened for having strong salt tolerance according to the comprehensive salt tolerance index at the germination and seedling stages. SN41, Emam, YN301, and JM262 were superior in salt-tolerance, and YM39, LM30, JM60, YN999, and SD29 were salt-tolerant. Our study suggests that the biomass of seedlings can be used as a key parameter for assessing wheat germplasm’s ability to withstand salt. Our results can provide some basic materials for cultivating new germplasm with salt tolerance and excavating the related genes of wheat.
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CLOUTIER, Y., L. PELLETIER, and R. MICHAUD. "DEVELOPMENT OF A TEST FOR FREEZING TOLERANCE IN YOUNG ALFALFA SEEDLINGS." Canadian Journal of Plant Science 70, no. 1 (1990): 307–10. http://dx.doi.org/10.4141/cjps90-036.
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An experiment was conducted to study the effects of seedling age on their ability to harden, and to determine whether cultivar × seedling age interaction could be identified for frost resistance. In the present study, 6- to 24-d-old alfalfa (Medicago sativa L.) seedlings were significantly more freezing-tolerant after cold-hardening than unhardened controls. Cold-hardened seedlings of age varying from 8 to 24 d were hardier than 6-d-old seedlings. No cultivar × seedling age interaction was found. The best separation of the cultivars occurred between 18 and 24 d. These findings provide additional information towards the development of a rapid and reliable test for estimating freezing tolerance in alfalfa.Key words: Freezing test, alfalfa, cold hardiness, seedlings
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Ye, Nenghui, Yuxing Wang, Huihui Yu, et al. "Abscisic Acid Enhances Trehalose Content via OsTPP3 to Improve Salt Tolerance in Rice Seedlings." Plants 12, no. 14 (2023): 2665. http://dx.doi.org/10.3390/plants12142665.
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Salt stress is one of the major environmental stresses that imposes constraints to plant growth and production. Abscisic acid (ABA) has been well-proven to function as a central integrator in plant under salt stress, and trehalose (Tre) has emerged as an excellent osmolyte to induce salt tolerance. However, the interacting mechanism between ABA and Tre in rice seedlings under salt stress is still obscure. Here, we found that the application of exogenous Tre significantly promoted the salt tolerance of rice seedlings by enhancing the activities of antioxidant enzymes. In addition, the expression of OsNCED3 was significantly induced by salt stress. The overexpression of the OsNCED3 gene enhanced the salt tolerance, while the knockout of OsNCED3 reduced the salt tolerance of the rice seedlings. Metabolite analysis revealed that the Tre content was increased in the OsNCED3-overexpressing seedlings and reduced in the nced3 mutant. The application of both ABA and Tre improved the salt tolerance of the nced3 mutant when compared with the WT seedling. OsTPP3 was found to be induced by both the ABA and salt treatments. Consistent with the OsNCED3 gene, the overexpression of OsTPP3 enhanced salt tolerance while the knockout of OsTPP3 reduced the salt tolerance of the rice seedlings. In addition, the Tre content was also higher in the OsTPP3-overexpressing seedling and lower in the tpp3 mutant seedling than the WT plant. The application of exogenous Tre also enhanced the salt tolerance of the tpp3 mutant plant. Overall, our results demonstrate that salt-increased ABA activated the expression of OsTPP3, which resulted in elevated Tre content and thus an improvement in the salt tolerance of rice seedlings.
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Zhang, Xijuan, Kai Liu, Chuanming Yang, et al. "Detection of Quantitative Trait Loci Associated with Alkaline Tolerance Using Recombinant Inbred Line Population Derived from Longdao5 × Zhongyouzao8 at Seedling Stage." Life 14, no. 9 (2024): 1151. http://dx.doi.org/10.3390/life14091151.
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Salt–alkaline stress is one of the most stressful occurrences, causing negative effects on plant development and agricultural yield. Identifying and utilizing genes that affect alkaline tolerance is an excellent approach to accelerate breeding processes and meet the needs for remediating saline–alkaline soil. Here, we employed a mapping population of 176 recombinant inbred lines (RILs) produced from a cross between alkali-tolerant Longdao5 and alkali-sensitive Zhongyouzao8 to identify the quantitative trait loci (QTLs) determining alkali tolerance at the seedling stage. For the evaluation of alkali tolerance, the recovered seedling’s average alkali tolerance index (ATI), root number (RN), root length (RL), seedling dry weight (SW), root dry weight (RW), and seedling height (SH) were assessed, together with their relative alkaline damage rate. Under alkaline stress, the ATI was substantially negative connected with the root number, seedling height, seedling dry weight, and root dry weight; however, it was considerably positive correlated with the relative alkaline damage rate of the root number and root dry weight. A total of 13 QTLs for the root number, root length, seedling height, seedling dry weight, root dry weight, and alkali tolerance index under alkaline stress were identified, which were distributed across chromosomes 1, 2, 3, 4, 5, 7, and 8. All of these QTLs formed two QTL clusters for alkali tolerance on chromosome 5 and chromosome 7, designated AT5 and AT7, respectively. Nine QTLs were identified for the relative alkaline damage rate of the root number, root length, seedling height, seedling dry weight, and root dry weight under alkali stress. These QTLs were located on chromosome 2, 4, 6, 7, 8, 9, and 12. In conclusion, these findings further strengthen our knowledge about rice’s genetic mechanisms for alkaline tolerance. This research offers clues to accelerate breeding programs for new alkaline-tolerance rice varieties.
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Noland, Thomas L., Rongzhou Man, and Michael Irvine. "Glyphosate tolerance of eastern white cedar: Third year results." Forestry Chronicle 93, no. 02 (2017): 190–93. http://dx.doi.org/10.5558/tfc2017-025.
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Little is known about the herbicide tolerance of eastern white cedar (Thuja occidentalis L.). To determine the sensitivity of cedar seedlings to timing and concentration of herbicide applications, glyphosate was applied to 2-year-old seedlings at three concentrations (1.04, 2.07, and 4.14 acid equivalent (ae) kg ha-1) at three times (July 28, August 10 and 31), at a research site in north central Ontario. Seedling survival, growth, and biomass three years after spraying were compared with those of seedlings in manual weeding (competition/weed free via manual weeding) and control (no weeding and therefore always competition/weeds) treatments. Only glyphosate applied at 4.14 ae kg ha-1 significantly reduced, by 27%, third year seedling survival. Pattern of sensitivity of cedar seedling growth to glyphosate was diameter>height. Seedlings treated with 2.07 and 4.14 ae kg ha-1 glyphosate had significantly less root biomass than those in the control plots, whereas only cedar treated with 4.14 ae kg ha-1 glyphosate had lower shoot biomass. Application timing made no difference in survival, growth, or final biomass. All glyphosate and the no weeding control treatments reduced root, shoot, and total biomass of cedar relative to the manually weeded seedlings.
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Poggi, Giovanni Maria, Simona Corneti, and Iris Aloisi. "The Quest for Reliable Drought Stress Screening in Tetraploid Wheat (Triticum turgidum spp.) Seedlings: Why MDA Quantification after Treatment with 10% PEG-6000 Falls Short." Life 14, no. 4 (2024): 517. http://dx.doi.org/10.3390/life14040517.
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Drought stress poses significant productivity challenges to wheat. Several studies suggest that lower malondialdehyde (MDA) content may be a promising trait to identify drought-tolerant wheat genotypes. However, the optimal polyethylene glycol (PEG-6000) concentration for screening seedlings for drought tolerance based on MDA quantification is not clear. The aim of this study was to verify whether a 10% (w/v) PEG-6000 concentration-induced water stress was reliable for discriminating between twenty-two drought-susceptible and drought-tolerant tetraploid wheat (Triticum turgidum spp. durum, turanicum, and carthlicum) accessions based on MDA quantification. To do so, its correlation with morpho-physiological traits, notoriously related to seedling drought tolerance, i.e., Seedling Vigour Index and Seedling Water Content, was evaluated. Results showed that MDA content was not a reliable biomarker for drought tolerance, as it did not correlate significantly with the aforementioned morpho-physiological traits, which showed, on the contrary, high positive correlation with each other. Combining our study with the cited literature, it clearly emerges that different wheat genotypes have different “water stress thresholds”, highlighting that using a 10% PEG-6000 concentration for screening wheat seedlings for drought tolerance based on MDA quantification is not reliable. Given the conflicting results in the literature, this study provides important insights for selecting appropriate methods for evaluating wheat seedling drought tolerance.
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Subramanian, M., K. Ganesan, W. W. Manuel, and T. Sundaram. "Seedling Tolerance for Dehydrating Wind." International Rice Research Newsletter 12, no. 2 (1987): 22–23. https://doi.org/10.5281/zenodo.7122611.
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This article 'Seedling Tolerance for Dehydrating Wind' appeared in the International Rice Research Newsletter series, created by the International Rice Research Institute (IRRI). The primary objective of this publication was to expedite communication among scientists concerned with the development of improved technology for rice and for rice based cropping systems. This publication will report what scientists are doing to increase the production of rice in as much as this crop feeds the most densely populated and land scarce nations in the world.
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Kaminski, John E., Peter H. Dernoeden, and Cale A. Bigelow. "Creeping Bentgrass Seedling Tolerance to Herbicides and Paclobutrazol." HortScience 39, no. 5 (2004): 1126–29. http://dx.doi.org/10.21273/hortsci.39.5.1126.
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The tolerance of creeping bentgrass (Agrostis stolonifera L.) seedlings to many herbicides has not been evaluated. Three field studies were conducted between fall and spring from 1998 to 2002 to assess creeping bentgrass seedling tolerance to five herbicides and paclobutrazol. The primary objectives of this investigation were to assess bentgrass tolerance to these chemicals when applied at various timings following seedling emergence, and establishment of new seedlings as influenced by potential soil residues in the spring following a fall application of the chemicals. Treatments were applied 2, 4, or 7 weeks after either `Crenshaw' or `L-93' creeping bentgrass seedlings had emerged. Siduron (6.7 and 9.0 kg·ha-1) and bensulide (8.4 kg·ha-1) were noninjurious when applied two weeks after seedling emergence (2 WASE). Bensulide (14 kg·ha-1), ethofumesate (0.84 kg·ha-1), prodiamine (0.36 kg·ha-1) and paclobutrazol (0.14 kg·ha-1) were too injurious to apply 2 WASE, but they were generally safe to apply at 4 WASE. Chlorsulfuron (0.14 kg·ha-1) was extremely phytotoxic to seedlings when applied 2 WASE. Plots were treated with glyphosate and overseeded the following spring. The overwintering soil residuals of prodiamine and bensulide (14.0 kg·ha-1) unacceptably reduced spring establishment. All other herbicides and paclobutrazol had little or no adverse residual effects on spring establishment. Chemical names used: N-(phosphonomethyl)gycline (glyphosate); (±)-(R*,R*)-beta-[(4-chlorophenyl)methyl]-alpha-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol); 2-ethoxy-2,3-dihydro-3,3-dimethyl-5-benzofuranyl methanesulfonate (ethofumesate); S-(0,0-diisopropyl phosphorodithioate) ester of N-(2-mercaptoethyl) benzenesulfonamide (bensulide); [1-(2-methylcyclohexyl)-3-phenylurea] (siduron); N3,N3-di-n-propyl-2,4-dinitro-6-(trifluoromethyl)-m-phenylenediamine (prodiamine); 2-chloro-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)aminocarbonyl] benzenesulfonamide (chlorsulfuron).
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Setyawan, Bayu, Niken Puspitasari, Agung Wahyu Susilo, and Indah Anita Sari. "Rootstock Characteristics of Three Combinations of Theobroma cacao L. Crosses on Different Water Availability." Pelita Perkebunan (a Coffee and Cocoa Research Journal) 34, no. 3 (2018): 137–45. http://dx.doi.org/10.22302/iccri.jur.pelitaperkebunan.v34i3.328.
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Climate change is universal phenomena which is importantly anticipated including cocoa plantation. Drought tolerance cocoa seedling is urgently neededto develop cocoa plantation. This paper studied possible drought tolerance of cocoa seedling through crossing between female parent KKM 22 with three maleparents BAL 209, KW 641, and KW 614. Progeny test was conducted in green house based on four water availability conditions: 25, 50, 75, and 100%. Root condition was recorded as rootstock parameters of three crossings. Result showed that root characteristics varied among crossing samples studied. The longestand hight volume root were recorded from KKM 22 x BAL 209 crossing. Seedling of KKM 22 x BAL 209 crossing tended to have long and wide root, while seedling of KKM 22 x KW 641 crossing tended to have a wide root type and seedling of KKM 22 x KW 614 tended to have a long root type. Based on drought tolerancy, seedling of KKM 22 x KW 641 crossing could be classified as drought tolerance while other two group progenies could be classified as susceptible to drought.To conclude, seedling of KKM 22 x KW 641 can be recommended for cocoa plantation in drought area.
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Rosbakh, Sergey, Vera Margreiter, and Bernardica Jelcic. "Seedlings of alpine species do not have better frost-tolerance than their lowland counterparts." Alpine Botany 130, no. 2 (2020): 179–85. http://dx.doi.org/10.1007/s00035-020-00237-4.
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Abstract In contrast to adult plants, little is known about the frost-tolerance of seedlings of alpine species, despite the fact that frost has been considered as one of the main factors limiting plant recruitment in high elevation. Here we report the results of a comparative study on seedling frost-tolerance of nine congeneric species pairs with lowland (0–900 m a.s.l.) and alpine (1800–2700 m a.s.l.) distribution. Similarly to adult alpine plants, we expected seedlings of alpine species to be more frost-tolerant than their lowland counterparts. Frost-tolerance was estimated under laboratory conditions by exposing seedlings to frost events from − 1 to − 9 °C, calculated as the temperature at which 50% of the seedlings were lethally damaged by frost (LT50). The LT50 values varied between − 1.95 and − 6.11 °C suggesting that seedling of all tested species could potentially survive mild and/or short frosts, but might be lethally damaged by severe and/or continuous frost events. The LT50 values for lowland and alpine species did not differ statistically and were on average − 3.96 ± 0.18 °C and − 4.16 ± 0.43 °C, respectively. These findings did not confirm our hypothesis that seedlings of alpine species have higher frost-tolerance than seedlings of lowland species. Four possible reasons could explain this pattern. They include (1) comparable levels of negative-stress in both lowland and alpine habitats, (2) opportunistic seed germination strategy in alpine plants, (3) peculiarities of our experimental set up and (4) potentially stronger effects of drought on alpine seedling survival than frost.
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Yan, Hai ling, Gui Li Shi, Wen Peng Shi, et al. "Effects of Different Temperature Treatments on Seed Germination and Seedling Growth of Rorippa sylvestris." Biotechnology Journal International 27, no. 6 (2023): 34–42. http://dx.doi.org/10.9734/bji/2023/v27i6704.
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Temperature is one of the important conditions for plant growth, and an important factor affecting the establishment and spread of invasive plants. In this study, the northern perennial invasive plant (Rorippa sylvestris) was taken as an example. By comparing the seed germination rate, germination potential, germination index and vigor index, the total number of leaves, root length, root length, vigor index, leaves of seedings, seedling biomass and root- shoot ratio under different temperature treatments (15, 20, 25, 30, 35, 40℃), the subordinate function was used to compare the temperature tolerance of R. sylvestris in seed germination. sylvestris in seed germination and seedling growth. To study the response and tolerance of seed germination and seedling growth of invasive R. sylvestris to different temperatures, the subordinate function was used to compare the temperature tolerance of R. sylvestris in seed germination and seedling growth. The results showed that high temperature promoted seed germination of R. sylvestris and limited radicle growth, and it had the most tolerance at different temperatures. The results showed that high temperature promoted seed germination of R. sylvestris and limited radicle growth, and it had the strongest tolerance at 35℃. Lower temperature was more beneficial to material accumulation of seedlings, and the tolerance of R. sylvestris was more favorable. The results provide theoretical basis for revealing the diffusion and invasion mechanism of R. sylvestris.
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Zhang, Hao, Li Jiang, Mohsin Tanveer, Jinbiao Ma, Zhenyong Zhao, and Lei Wang. "Indexes of Radicle are Sensitive and Effective for Assessing Copper and Zinc Tolerance in Germinating Seeds of Suaeda salsa." Agriculture 10, no. 10 (2020): 445. http://dx.doi.org/10.3390/agriculture10100445.
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Euhalophytes, such as Suaeda salsa, are ideal candidates to remediate heavy metal-polluted saline soils. However, the metal tolerance ability of dimorphic seeds and subsequent seedlings is largely unknown. This study investigated the tolerance of S. salsa seeds to different concentrations of Cu2+ (0–300 mM) and Zn2+ (0–300 mM) during germination and seedling growth stages. Results showed that dimorphic seeds of S. salsa had high metal tolerance during germination, and even germinated under 300 mM Cu and Zn treatments. However, seedling growth was more sensitive to metal solutions and radicle growth was almost completely inhibited by Cu at 10 mM, and by Zn at 50 mM. Germinating seeds and seedlings of S. salsa had a higher metal toxicity threshold of Zn than that of Cu. In all indexes, indexes of radicle were the most sensitive and effective indicator of metal tolerance. Seeds of S. salsa germinated successfully and seedlings survived under high Zn and Cu stress. The results suggest that S. salsa could be sown directly in heavy metal-contaminated soils for phytoremediation.
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da Silva, Poliana Noemia, Vinícius Politi Duarte, Evaristo Mauro de Castro, Bruno Montoani Silva, Josiel de Jesus Santos, and Fabricio José Pereira. "Compaction of Iron Mining Tailings Impairs Seedling Emergence of Schinus terebinthifolia but Vigor Features Show Tolerance During Early Growth." Forests 16, no. 6 (2025): 950. https://doi.org/10.3390/f16060950.
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Soil compaction is a well-known harmful process for germination and seedling growth. Studies about compaction in mining tailings have been neglected despite being essential for the reforestation of impacted areas. This work evaluated the effects of compaction of iron mining tailings on the seedling emergence, early growth, and photosynthesis of Schinus terebinthifolia Raddi, a tolerant species with potential for reforestation. Experiments were implemented in a greenhouse where seeds of S. terebinthifolia were sown in iron mining tailings with four compaction treatments: (1) an uncompacted dry tailing, (2) uncompacted moistened tailing, (3) compacted dry tailing, and (4) compacted moistened tailing. Penetration resistance, seedling emergence, emergence speed index, seedling biometry, and photochemical traits were evaluated. Compacted moistened tailings showed the highest penetration resistance and uncompacted dry tailings the lowest. Other treatments showed intermediate means. The compacted moistened tailings produced the lowest seedling emergence rate and emergence speed index, and these parameters showed the highest means at uncompacted dry tailings with other treatments showing intermediate means. The compaction did not affect the seedling’s biometric parameters, with a similar growth among all treatments. S. terebinthifolia seedlings showed improved growth parameters during the experimental period, evidencing the potential of the species for the reforestation of impacted areas by iron mining tailings.
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Hall, Kip E., Larry H. McCormick, and Larry J. Kuhns. "Black Alder Seedlings Demonstrate Tolerance to Preemergence Herbicides in Preliminary Trials1." Northern Journal of Applied Forestry 3, no. 2 (1986): 76–79. http://dx.doi.org/10.1093/njaf/3.2.76.
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Abstract Seven preemergence herbicides, atrazine, metolachlor, napropamide, oryzalin, oxadiazon, oxyfiuorfen, and simazine, were screened for phytotoxic effects on newly planted black alder seedlings. All treatments containing atrazine significantly reduced seedling survival, as did simazine treatments greater than 3.4 kg/ha. The simazine rate of 3.4 kg/ha, the napropamide rate of 26.9 kg/ha, and metolachlor rates greater than 3.4 kg/ha temporarily stunted seedling height growth early in the first growing season. Temporary stunting was also observed for the highest rates of the granular and emulsifiable concentrate formulations of oxyfluorfen, 9.0 and 4.5 kg/ha respectively. However, those treatments that temporarily stunted height growth had no significant effect on seedling survival. Excluding atrazine, all of the preemergence herbicides evaluated in this study could be safely applied to newly planted black alder seedlings with no significant mortality or growth inhibition, providing the rate guidelines previously mentioned are observed. North. J. Appl. For. 3:76-79, June 1986.
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Abdelmalik, Abdelmalik M. "Enhanced Growth and Drought Resistance in Seedlings of Acacia tortilis due to Inoculation of Arbuscular Mycorrhiza Fungi and Bacillus subtilis." International Journal of Agriculture and Biology 26, no. 06 (2021): 750–60. http://dx.doi.org/10.17957/ijab/15.1891.
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A shade house experiment was conducted in Saudi Arabia to evaluate the impact of a mixture of three arbuscular mycorrhiza fungi (AMF) namely Funneliformis mosseae, Rhizophagus intraradices and Claroideoglomus etunicatum, a bacterium Bacillus subtilis, and their combinations on the growth and drought resistance potential of Acacia torilis seedlings under moderate and water deficit-stress. Thus, inoculants treatments (AMF, Bacillus subtilis, AMF+Bacillus, and control) and several watering intervals (1, 2, 3 and 4 weeks) were applied. Inoculation of AMF and Bacillus to A. tortilis seedlings found effective in terms of improved seedling growth. AMF and combined inoculation resulted in a larger shoot (shoot fresh and dry weights, seedling height, leaf number, leaf area) and root development (root fresh and dry weights, root length, root surface area, and root volume) as compared to the non-inoculated seedlings. Single inoculants of B. subtilis, showed better improvement in 1- and 2-week watering intervals compared to the control. Inoculated seedlings showed lower proline accumulation than non-inoculated seedlings, and thus improved seedling resistance to water deficit-stress. Mycorrhizal and mixed inoculation enhanced the amount of chlorophyll in the seedling’s leaves. Furthermore, seedlings with AMF and co-inoculants showed better drought tolerance even at 3- and 4-week watering intervals. © 2021 Friends Science Publishers
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Bachand, George D., John D. Castello, Michail Schaedle, Stephen V. Stehman, and William H. Livingston. "Effects of tomato mosaic Tobamovirus infection on red spruce seedlings." Canadian Journal of Forest Research 26, no. 6 (1996): 973–81. http://dx.doi.org/10.1139/x26-107.
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Height, weight, root volume, shoot length, needle length and weight, and total chlorophyll content were measured for both control and tomato mosaic Tobamovirus (ToMV)-inoculated red spruce (Picearubens Sarg.) seedlings in each of five, 3-month growth periods. Mean bud-break rating was determined for each seedling in growth period 5. In January 1995 the freezing tolerance of control and ToMV-infected seedlings was determined. Approximately 85% of the inoculated seedlings became infected with ToMV, as determined by enzyme-linked immunosorbent assay of young root tissue. Reduction in seedling height, weight, root volume, bud break, and mean shoot length of infected seedlings was observed when compared with control seedlings. The rate of increase over time in height, weight, and root volume was lower (54, 57, and 52%, respectively) in infected seedlings compared with control seedlings. Additionally, needles of infected seedlings were less susceptible to freezing damage than those of control seedlings. However, virus infection had no effect on the freezing tolerance of roots.
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Elliott, R. H., C. Franke, and G. F. W. Rakow. "Effects of seed size and seed weight on seedling establishment, vigour and tolerance of Argentine canola (Brassica napus) to flea beetles, Phyllotreta spp." Canadian Journal of Plant Science 88, no. 1 (2008): 207–17. http://dx.doi.org/10.4141/cjps07059.
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A 3-yr study was conducted on four Brassica napus L. cultivars to determine the effects of seed size and seed weight on the performance and tolerance of canola seedlings to feeding damage by flea beetles, Phyllotreta spp. (Coleoptera: Chrysom elidae). Seed lots of a doubled haploid cultivar Cyclone, hybrid cultivar AC H102 and two open-pollinated cultivars Profit and AC Elect were sieved to obtain small, medium, large and very large seeds (1.4–1.6, 1.6–1.8, 1.8–2.0 and 2.0–2.2 mm diameter, respectively). Under controlled environmental conditions, leaf area, shoot weight and biomass of seedlings from large and very large seeds were 1.3–2.0 times greater than those of seedlings from small seeds. Under field conditions without insecticides, seedlings from small seeds of each cultivar had the highest flea beetle damage, poorest establishment, and lowest shoot weight, biomass and yield. Compared with small seeds, large seeds improved seedling establishment, shoot weight, biomass and yield by 1.1, 1.6–2.0, 3.0–3.5 and 1.5 times, respectively. Results indicated that seedlings from large seeds are more vigorous and tolerant to flea beetle damage than seedlings from medium or small seeds. Seedling vigour and tolerance was due to a higher initial shoot biomass and higher growth rate when flea beetle damage was severe. When damage exceeded 50%, large heavy seeds had the best stand establishment, best shoot growth and highest yield in each cultivar. Key words: Canola, flea beetles, seed size, seed weight, seedling vigour, tolerance
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Rosyara, Umesh R., Amrit A. Ghimire, Sushil Subedi, and Ram C. Sharma. "Variation in south Asian wheat germplasm for seedling drought tolerance traits." Plant Genetic Resources 7, no. 1 (2009): 88–93. http://dx.doi.org/10.1017/s1479262108994247.
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Higher seedling vigour and greater coleoptile length are important for early establishment of wheat crops and subsequently higher grain yield in many dry environments. Seedling vigour includes those seed properties that determine the potential for rapid, uniform emergence and development of normal seedlings under a wide range of field conditions. Genotypes with the widely used gibberellic acid (GA)-insensitive dwarfing genes Rht-B1b and Rht-D1b have good partitioning and grain yield under optimal conditions, but may perform poorly under stressed conditions due to poor crop establishment. Breeding programmes are in search of GA-sensitive dwarfing genes that do not affect seedling vigour under dry conditions. This study evaluated 40 genotypes currently used in wheat breeding programmes of south Asia for seedling vigour-related traits in greenhouse and field experiments during 2006–2007 at IAAS, Rampur, Nepal. Wide variation in coleoptile length, seedling vigour, as well as sensitivity to GA was observed. Among the genotypes studied, there were positive correlations among coleoptile length, leaf width and plant height. Genotypes, SW89-5193, SW89-5422/NL251 and SW89-5422, were found to have longer coleoptile, higher seedling vigour and response to GA application. This shows a promise for their further applications in the breeding programmes.
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Krishnan, Lalitha, Deepak Barua, and Mahesh Sankaran. "Dry-forest tree species with large seeds and low stem specific density show greater survival under drought." Journal of Tropical Ecology 35, no. 1 (2019): 26–33. http://dx.doi.org/10.1017/s0266467418000421.
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AbstractTree establishment in tropical dry forests is constrained by drought-related seedling mortality during early stages of recruitment. Predicted increases in the duration of growing-season droughts in the future pose a significant threat to these ecosystems that could significantly alter their vegetation structure and composition. Here, we examined drought tolerance in seedlings of seven common dry-forest tree species from the Indian subcontinent. We conducted a dry-down experiment on 3-wk-old seedlings, and asked whether the key plant functional traits, specific leaf area (SLA), leaf dry matter content (LDMC), seed size and stem specific density (SSD) were good predictors of seedling growth under well-watered conditions, and survival during drought. Seedlings displayed substantial drought tolerance with most seedlings surviving for more than 2 wk under protracted drought. Seed size in combination with SLA predicted seedling growth under well-watered conditions and seed size predicted survival under drought. In contrast to our expectations, seedlings with lower SSD survived for longer without water. Our results suggest that dry-forest species will be differentially affected by the predicted increases in the duration of growing-season droughts, and detrimental effects will be more severe for species with smaller seeds.
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Elliott, R. H., L. W. Mann, and O. O. Olfert. "Effects of seed size and seed weight on seedling establishment, seedling vigour and tolerance of summer turnip rape (Brassica rapa) to flea beetles, Phyllotreta spp." Canadian Journal of Plant Science 87, no. 2 (2007): 385–93. http://dx.doi.org/10.4141/p06-166.
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A 3-yr study was conducted on three synthetic Brassica rapa L. cultivars to determine the effects of seed size and seed weight on seedling establishment, seedling growth and susceptibility to feeding damage by flea beetles, Phyllotreta spp. (Coleoptera: Chrysomelidae). Seed lots of AC Boreal, Fairview and Hysyn 110 were sieved to obtain small, medium and large seeds (1.4–1.6, 1.6–1.8 and 1.8–2.0 mm, respectively). In the laboratory, seedlings grown from large seeds had the largest cotyledons, highest shoot dry weight and highest biomass. Shoot weights increased as seed size increased. Sized seeds of the three cultivars were grown in the field without insecticides in 1998–2000. Seedlings of small seeds had the highest flea beetle damage and poorest seedling establishment. Shoot dry weight and biomass 14–35 d after planting increased as seed size and seed weight increased. Compared with small seeds, large seeds improved shoot dry weight, biomass and seed yield by 13–43, 25–57 and 12%, respectively. Results indicated that seedlings of medium and large seeds are more vigorous and tolerant to flea beetle damage than seedlings of small seeds. Tolerance was due to a higher initial seedling weight rather than higher relative growth rate. Shoot dry weights, biomass and yield of the three cultivars were more strongly correlated with 1000-seed weight than with seed diameter. Key words: Canola, flea beetles, seed size, seedling vigour, tolerance, seed weight
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Huang, Zhenying, and Yitzchak Gutterman. "Seedling desiccation tolerance of Leymus racemosus (Poaceae) (wild rye), a perennial sand-dune grass inhabiting the Junggar Basin of Xinjiang, China." Seed Science Research 14, no. 2 (2004): 233–39. http://dx.doi.org/10.1079/ssr2004172.
Full textAbstract:
Leymus Racemosus, The Mammoth Wild Rye, Is A Rhizomatous Perennial Grass, Mainly Distributed In The Moving Or Semi-Stabilized Sand Dunes In Deserts Of The Junggar Basin In Xinjiang, China. The Revival Ability Of The Young Seedling After Periods Of Desiccation Can Be Influenced By Several Factors: (1) The Stage Of Seedling Development – The Later The Stage At Dehydration, The Longer The Root Length And The Lower Is The Percentage Of Seedlings That Survive; (2) The Length Of The Period Of Desiccation – The Longer The Period That The Seedlings Are Under Desiccation, The Lower Is The Percentage Of Seedlings That Survive; (3) Endosperm Size – The Smaller The Proportion Of Endosperm That Remains In The Caryopses, The Lower Is The Percentage Of Seedlings That Revive, Determined By (A) The Stage Of Seedling Development, And (B) The Proportion Of The Endosperm That Is Removed By Cutting; And (4) Caryopsis Size – The Larger The Polymorphic Caryopses, The Higher Is The Percentage Of Young Seedlings That Revive From Periods Of Desiccation. The Physiological And Ecological Implications Of L. Racemosus Seedling Desiccation Tolerance Are That Under Extreme Desert And Unpredictable Environmental Conditions, The Chances Of Seedling Establishment Are Increased.
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Pagano, Andrea, Giulia Folini, Paola Pagano, et al. "ROS Accumulation as a Hallmark of Dehydration Stress in Primed and Overprimed Medicago truncatula Seeds." Agronomy 12, no. 2 (2022): 268. http://dx.doi.org/10.3390/agronomy12020268.
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Seed priming protocols implement incomplete imbibition phases, as well as physical, chemical or biological treatments, to activate pre-germinative metabolism and stress response, thus improving germination performances, seedling establishment and stress tolerance according to agricultural productivity requirements. The dehydration phase following priming treatments represents a critical variable, since an excessively prolonged imbibition (overpriming) impairs desiccation tolerance, compromising seed viability and seedling establishment. Priming protocols generally optimize imbibition-dehydration timing empirically to avoid overpriming. Hence, a better understanding of the dynamics underlying the loss of desiccation tolerance represents a promising route to test and develop efficient and cost-effective priming techniques. In the present work, priming and overpriming conditions were defined to explore the role of desiccation tolerance in seed priming efficiency in the model legume Medicago truncatula. The positive effects of hydropriming and kinetin-mediated hormopriming on germination parameters were screened in combination with conditions of short/prolonged priming and mild/severe overpriming. Biometric analyses highlighted contrasting responses in terms of germination performances and seedling development, while ROS (reactive oxygen species) levels measured during dehydration positively correlate with the loss of desiccation tolerance in early seedlings, suggesting possible applications to monitor priming progression and predict overpriming occurrence.
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Tang, Lisi, Wen Li, Qikun Yu, Zongjiu Sun, and Peiying Li. "Assessing Germplasm Variation and Tolerance Thresholds of Bermudagrass (Cynodon dactylon) to Neutral and Alkaline Salt Stress in Ecological Restoration." Agronomy 14, no. 9 (2024): 2023. http://dx.doi.org/10.3390/agronomy14092023.
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Bermudagrass (Cynodon dactylon), a salt-tolerant species surviving in environments with pH up to 9.3, and it exhibits variable germination responses under salt and alkaline stress. This study evaluates the impact of neutral and alkali salts with varying pH levels on bermudagrass seed germination. Six bermudagrass germplasm accessions were analyzed using neutral (NaCl: Na2SO4 = 1:1, pH 6.12–7.14) and alkali (NaHCO3:Na2CO3 = 1:1, pH 9.62–9.90) salt treatments. Salt concentrations ranged from 0 to 250 mmol/L, with increments of 25 mmol/L. The assessed parameters included seed germination rate, germination potential, germination index, radicle length, plumule length, seedling weight, and radicle and plumule length ratio. The salt tolerance threshold of each germplasm was calculated using a linear regression fitting model. Critical indicators of salt tolerance were selected through stepwise regression, and the salt-alkali tolerance ranking was determined using a combined membership function and discriminant analysis. The results indicated that the total score decreased with increasing salt concentration under neutral salt stress. Alkali salt stress was more damaging to bermudagrass seedlings than neutral salt stress, inhibiting germination at 50 mmol/L. Neutral salt tolerance thresholds ranged from 31.7 to 207.7 mmol/L, while alkaline salt tolerance thresholds ranged from 16.9 to 53.3 mmol/L. The six germplasm accessions exhibited different responses to salt and alkali stress. Key indicators for neutral salt tolerance included plumule length, radicle and plumule length ratio, and seedling weight. For alkali salt tolerance, key indicators were germination potential, radicle length, and seedling weight, which can be used to screen for resistant germplasms. Our study demonstrates that alkaline salts inhibit seed germination and seedling growth more than neutral salts, and pH affects root growth and the radicle-to-plumule length ratio in seedlings. This research has significant ecological implications, providing insights into the adaptation strategies of bermudagrass in salt-affected and alkaline environments, which could aid in the restoration and management of degraded ecosystems.
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Vergara, Georgina, and Abdelbagi Ismael. "Development and Characterization of Rice Lines Carrying both Sub1 and Anaerobic Germination Tolerance: SUB1A does not Inhibit AG [RESEARCH NOTE]." Philippine Agricultural Scientist 106, no. 3 (2023): 330–37. http://dx.doi.org/10.62550/dcd038023.
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Accelerated coleoptile elongation in flooded soils allowed seedling shoots to reach the water surface to maintain gas exchange and CO2 fixation. Rice genotypes with tolerance of flooding during germination (anaerobic germination, AG) exhibited fast coleoptile elongation as an escape mechanism. On the other hand, tolerance of complete submergence during the vegetative stage, conferred by SUB1A, involved growth retardation to conserve energy for maintenance metabolism, with resumption of growth upon de-submergence. Combining genes controlling flood tolerance at these two stages with contrasting mechanisms was necessary in flood-prone areas for protection during germination under direct seeding and during vegetative stage. Breeding lines combining AG + Sub1 were used to determine the timing of the expression of SUB1A and elucidate its impact when combined with tolerance of flooding during seed germination and to evaluate seedling performance under complete submergence. Time-points for SUB1A expression in IR64-Sub1 and AG + Sub1 lines germinated under hypoxia or submerged for 30 h at vegetative stage showed that during flooding treatment, SUB1A and SUB1C expression was inhibited in young seedlings (< 6 d old) in IR64-Sub1 and at 2 and 4 d of seedling growth under hypoxia in AG + Sub1 materials. SUB1A was weakly expressed in AG + Sub1 starting at seedling age of 6 d following 1 d of complete submergence, indicating that expression of SUB1A may be stage-specific. Physiological tests showed higher percentage of survival of AG + Sub1 lines under hypoxia, comparable to that of AG tolerant check and significantly different from intolerant check IR42, indicating that the presence of SUB1A does not affect tolerance of flooding during germination. When seedlings were completely submerged, Sub1 expression was not inhibited by the presence of AG and tolerant genotypes showed suppressed elongation that was significantly different from intolerant check IR42. Despite their contrasting mechanisms of tolerance, combining AG with Sub1 provides multiple flooding tolerance from early crop establishment using direct seeding through to the vegetative stages.
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Wu, Yingbao, Gaoyang Zhang, Chao Zhang, et al. "Pooled Mapping of QTLs Associated With Salt Tolerance Traits at Seedling Stage in Rice." Bangladesh Journal of Botany 53, no. 2 (2024): 405–10. http://dx.doi.org/10.3329/bjb.v53i2.74431.
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Salt stress has been identified as a vital limiting factor affecting rice output across the world. In rice, the salt tolerance nature is complicated, since it is dependent on different components and is lowly heritable. Consequently, it is a key method to breed salt-tolerant varieties for improving rice output upon salt stress. To investigate the genetic foundation for salt stress tolerance of rice seedlings (Oryza sativa L.), bulked segregant analysis coupled with whole-genome sequencing (BSA-seq) was performed in QTL mapping on the huge F2 population including totally 2,500 plants obtained through crossing the indica rice variety 1892S with the japonica rice variety Huaidao 5 (HD5). In BSA-seq, only extremely-sensitive (ES) and extremely-tolerant (ET) seedlings were utilized, making it not difficult for identification with no requirement of quantitative analysis. Therefore, the seedling survival state was an appropriate indicator trait in BSA-seq. HD5 in seedling stage exhibited enhanced tolerance to extended salt stress when compared with 1892S. The DNA pools prepared based on 235 ES together with 165 ET seedlings of F2 population through block regression mapping (BRM) were analyzed, and a QTL was mapped onto chromosome 3 and termed QTL qSLST3.1. There were numerous rice salt tolerance-associated QTLs on chromosome 3 in seedling stage, but just one was situated in the confidence interval of qSLST3.1. These QTLs did not have identical positions. So qSLST3.1 should be the new QTL. Moreover, our results can shed more lights on marker-assisted salt-resistant variety breeding and positional cloning of rice salt tolerance trait-related genes. Bangladesh J. Bot. 53(2): 405-410, 2024 (June)
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Bigras, Francine. "Frost Tolerance of Black Spruce Seedlings (Picea Mariana) during Budbreak." HortScience 30, no. 4 (1995): 849C—849. http://dx.doi.org/10.21273/hortsci.30.4.849c.
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Spring frosts frequently cause significant damage to conifer seedlings during bud flushing and shoot elongation in forestry nurseries. To ensure adequate protection, levels of frost sensitivity must be known during these stages of development. Eight-month-old, containerized, black spruce seedlings were submitted to freezing temperatures of 0, –4, –6, –8, and –10C for 1, 2, 3, 4, 5, and 6 h at the following stages: 1) nonswollen buds; 2) swollen buds; 3) bud scales bursting, needle tips emerging; and 4) shoot elongation, 1 to 5 cm. After the treatments, seedlings were grown for 90 days in a greenhouse. Seedling survival then was estimated; dead seedlings discarded; and damage to buds, needles, and roots and shoot increment and diameter were measured on the remaining seedlings. Results show that frost sensitivity increases with the developing bud and shoot. A decrease in seedling and bud survival was noted with an increase in time of exposure (stages 2, 3, 4); otherwise, time exposure has no effect. Damage to needles and roots increases and diameter decreases with decreasing temperatures at all stages. Shoot increment was influenced by decreasing temperatures at stages 2 and 3 only.
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Li, Junming, Lei Liu, Yuling Bai, et al. "Seedling salt tolerance in tomato." Euphytica 178, no. 3 (2010): 403–14. http://dx.doi.org/10.1007/s10681-010-0321-x.
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van der Moezel, PG, LE Watson, GVN Pearce-Pinto, and DT Bell. "The Response of Six Eucalyptus Species and Casuarina obesa to the Combined Effect of Salinity and Waterlogging." Functional Plant Biology 15, no. 3 (1988): 465. http://dx.doi.org/10.1071/pp9880465.
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Seedlings of Eucalyptus camaldulensis, E. comitae-vallis, E. kondininensis, E. lesouefii, E. platycorys, E. spathulata and Casuarina obesa were grown in a glasshouse under non-saline drained, saline drained, non-saline waterlogged, and saline waterlogged conditions for 3 months. Measurements were taken of seedling height, seedling survival and the concentration of Na, K, Ca, Mg and Cl in plant tissues. Production of specialised roots containing aerenchyma in E. camaldulensis and C. obesa enabled these species to tolerate non-saline waterlogged conditions. Saline, but freely drained conditions reduced seedling growth for all species but only E. kondininensis recorded seedling deaths. C. obesa was the species most tolerant of saline waterlogged conditions with no seedling deaths and a lower reduction in growth compared to the Eucalyptus species. Exclusion of Na and Cl, together with the production of specialised roots by C. obesa are suggested as the probable factors relating to the high seedling tolerance in saline waterlogging. The species with highest tolerance to non-saline waterlogging were more tolerant of saline waterlogged conditions. The importance of this result for evaluating trees to be used in the rehabilitation of secondary salinised land in Australia is discussed.
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Wang, Jilin, Cheng Huang, Lijuan Tang, et al. "Identification of Submergence Tolerance Loci in Dongxiang Wild Rice (DXWR) by Genetic Linkage and Transcriptome Analyses." International Journal of Molecular Sciences 26, no. 5 (2025): 1829. https://doi.org/10.3390/ijms26051829.
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The submergence tolerance of rice is a key factor in promoting rice direct seeding technology and resisting flood disasters. Dongxiang wild rice (DXWR) has strong submergence tolerance, but its genetic basis is still unclear. Here, we report quantitative trait loci (QTLs) analysis for hypoxic germination rate (HGR), hypoxic seedling rate (HSR), budlet submergence survival rate (BSSR) and seedling submergence survival rate (SSSR) using a linkage map in the backcross recombinant inbred lines (BRILs) that were derived from a cross of DXWR, and an indica cultivar, GZX49. A total of 20 QTLs related to submergence tolerance of rice were detected, explaining phenotypic variations ranging from 2% to 8.5%. Furthermore, transcriptome sequencing was performed on the seeds and seedlings of DXWR before and after submergence. During the seed hypoxic germination and seedling submergence stages, 6306 and 3226 differentially expressed genes (DEGs) were detected respectively. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were conducted on these differentially expressed genes. Using genetic linkage analysis and transcriptome data, combined with qRT-PCR, sequence comparison, and bioinformatics, LOC_Os05g32820 was putatively identified as a candidate gene for qHGR5.2 co-located with HGR and SSSR. These results will provide insights into the mechanism of rice submergence tolerance and provide a basis for improving rice submergence tolerance.
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SAYYARI, Mohammad, Fardin GHANBARI, Sajad FATAHI, and Fatemeh BAVANDPOUR. "Chilling Tolerance Improving of Watermelon Seedling by Salicylic Acid Seed and Foliar Application." Notulae Scientia Biologicae 5, no. 1 (2013): 67–73. http://dx.doi.org/10.15835/nsb518293.
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Chilling temperatures lead to numerous physiological disturbances in the cells of chilling-sensitive plants and result in chilling injury and death of tropical and subtropical plants such as watermelon. In this study, the possibility of cold stress tolerance enhancing of watermelon seedling (Citrullus lanatus) by exogenous application of Salicylic acid (SA) was investigated. SA was applied through seed soaking or foliar spray at 0, 0.5, 1 and 1.5 mM concentration. After SA treatment, the seedlings were subjected to chilling 5 h/day at 4°C for 5 days. Statistical analysis showed significant effects of the application methods and SA concentrations on plant growth parameters, photosynthetic pigments, electrolyte leakage, proline and chilling injury index. SA application improved growth parameters and increased chlorophyll content of watermelon seedling subjected to chilling stress and provided significant protection against chilling stress compared to non-SA-treated seedlings. Although two SA application methods improved chilling stress tolerance, seed soaking method provided better protection compared to foliar spray method. SA ameliorated the injury caused by chilling stress via inhibiting proline accumulation and leaf electrolyte leakage. The highest cold tolerance was obtained with 0.5 mM SA application. Results indicate that SA could be used effectively to protect watermelon seedling from damaging effects of chilling stress at the early stages of growth.
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Couvillon, Gary A. "Cercis canadensis L. Seed Size Influences Germination Rate, Seedling Dry Matter, and Seedling Leaf Area." HortScience 37, no. 1 (2002): 206–7. http://dx.doi.org/10.21273/hortsci.37.1.206.
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Several studies with annual crops have shown that large seeds improve percent germination, seedling growth, and uniformity, yield, seedling vigor, and stress tolerance. Little information is available on the influence of seed size on the resulting seedlings of woody plant species. Cercis canadensis L. seeds were divided into large and small seed size fractions and the seeds scarified, stratified, and planted. A larger percentage of large seeds germinated than did small seeds. Seedlings from large seeds had a greater peak and germination value than small seeds, indicating greater vigor and a more rapid germination rate thus more uniform seedlings. Seedlings from large seeds, as indicated by fresh and dry weights, were larger and contained a greater leaf area than those produced by small seed.
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NOREEN, Tabinda, Muhammad KABIR, Muhammad Zafar IQBAL, Muhammad SHAFIQ, and Zia-ur-Rehman FAROOQI. "ANALYSIS OF EFFECTS OF LEAD AND IRON TREATMENT ON EARLY SEEDLING GROWTH OF ALBIZIA LEBBECK L. (BENTH.) AND EUCALYPTUS GLOBULUS LABILL. IN VITRO STUDIES." Journal of Plant Development 29, no. 1 (2022): 95–102. http://dx.doi.org/10.47743/jpd.2022.29.1.910.
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Pollution by heavy metals in the environment is a worldwide problem. The aim of the research study was to record the effect of lead (Pb) and iron (Fe) elements on early seedling growth of Albizia lebbeck L. (Benth.) and Eucalyptus globulus Labill. The obtained results showed that higher level of lead (Pb) and iron (Fe) elements treatment present in the substrate had wide a spectrum of toxicity activity against seedlings growth performance of A. lebbeck and E. globulus as compared to control in lab conditions. Statistically analyzed data showed that seedling growth of A. lebbeck and E. globulus were reduced significantly (p<0.05) with increased concentrations of Pb and Fe 5 to 20 ppm as compared control (0 ppm). The percentage of seedling tolerance index of A. lebbeck and E. globulus showed different level of iron and lead. A. lebbeck showed greater tolerance indices (61.19%) in the presence of Fe than Pb treatments (50.39%). It was also noted that tolerance indices of E. globulus was reduced more in Fe (41.19%) as compared to Pb treatments (55.32%).
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Ham, Tae-Ho, Yebin Kwon, Yoonjung Lee, Jisu Choi, and Joohyun Lee. "Genome-Wide Association Study Reveals the Genetic Basis of Cold Tolerance in Rice at the Seedling Stage." Agriculture 11, no. 4 (2021): 318. http://dx.doi.org/10.3390/agriculture11040318.
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We conducted a genome-wide association study (GWAS) of cold tolerance in a collection of 127 rice accessions, including 57 Korean landraces at the seedling stage. Cold tolerance of rice seedlings was evaluated in a growth chamber under controlled conditions and scored on a 0–9 scale, based on their low-temperature response and subsequent recovery. GWAS, together with principal component analysis (PCA) and kinship matrix analysis, revealed four quantitative trait loci (QTLs) on chromosomes 1, 4, and 5 that explained 16.5% to 18.5% of the variance in cold tolerance. The genomic region underlying the QTL on chromosome four overlapped with a previously reported QTL associated with cold tolerance in rice seedlings. Similarly, one of the QTLs identified on chromosome five overlapped with a previously reported QTL associated with seedling vigor. Subsequent bioinformatic and haplotype analyses revealed three candidate genes affecting cold tolerance within the linkage disequilibrium (LD) block of these QTLs: Os01g0357800, encoding a pentatricopeptide repeat (PPR) domain-containing protein; Os05g0171300, encoding a plastidial ADP-glucose transporter; and Os05g0400200, encoding a retrotransposon protein, Ty1-copia subclass. The detected QTLs and further evaluation of these candidate genes in the future will provide strategies for developing cold-tolerant rice in breeding programs.
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Temel, Fatih, G. R. Johnson, and W. T. Adams. "Early genetic testing of coastal Douglas-fir for Swiss needle cast tolerance." Canadian Journal of Forest Research 35, no. 3 (2005): 521–29. http://dx.doi.org/10.1139/x04-183.
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The possibility of early testing coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) for Swiss needle cast (SNC; caused by Phaeocryptopus gaeumannii (Rohde) Petrak) tolerance was investigated using 55 Douglas-fir families from western Oregon. Seedlings were inoculated with P. gaeumannii naturally in the field and were visually scored for a variety of SNC symptom traits (i.e., needle and foliage color, and retention) at the seedling stage (age 2) and in "mature" (ages 10 and 12) trees at two test sites for both the seedling and mature ages. Seedlings were also assessed in the laboratory for SNC symptom traits, for proportion of needle stomata occluded with pseudothecia (PSOP), and for amount of P. gaeumannii DNA in needles. Although families differed significantly at both ages for all SNC symptom traits and for PSOP, they did not differ for amount of fungal DNA. Thus, genetic variation in SNC symptoms appears to be primarily due to differences in tolerance to the disease rather than to resistance to infection per se. Estimated individual-tree heritabilities for SNC symptom traits were low to moderate (mean hi2 = 0.19, range 0.060.37) at both ages, and within each age-class these traits were moderately to strongly genetically correlated (mean rA = 0.69, range 0.420.95). Type B genetic correlations between SNC symptom traits in seedlings and mature trees ranged from 0 to 0.83 and were weakest for traits measured in the laboratory. Genetic gain estimates indicated that family selection for SNC tolerance (i.e., greener needles or greater foliage retention) at the seedling stage can be very effective in increasing tolerance in older trees.
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Reuling, Laura F., Alan J. Z. Toczydlowski, Robert A. Slesak, and Marcella A. Windmuller-Campione. "Effects of Biochar on Drought Tolerance of Pinus banksiana Seedlings." International Journal of Plant Biology 14, no. 3 (2023): 811–24. http://dx.doi.org/10.3390/ijpb14030060.
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Drought is a major stressor of tree seedlings regarding both natural and artificial regeneration, especially in excessively drained, sandy outwash soils. While climate change is expected to cause an increase in the total annual precipitation in the Upper Midwest, USA, the timing of the precipitation is predicted to result in longer periods of drought during the growing season. Biochar, a material created through the pyrolysis of organic matter, such as wood waste, has been proposed as a soil amendment that may increase the water holding capacity of a soil. Biochar has mostly been studied in agricultural settings, and less is known about the impact of biochar on forest soils and tree seedlings. We used a greenhouse experiment to test the ability of biochar to improve the drought tolerance of jack pine (Pinus banksiana) seedlings via increased soil water holding capacity. The seedlings were planted in sandy soil treated with three levels of biochar (none, 3% by weight, and 6% by weight) in two experiments, one manipulating the timing of drought onset and the other controlling the amount of water that seedlings received. Our results showed no significant effects of biochar on seedling survival, growth, or physiology under drought conditions. While this outcome did not support the hypothesis that biochar would increase seedling performance, the biochar amendments did not negatively affect seedlings, indicating that biochar may be added to soil for carbon storage without having negative short-term impacts on tree seedlings.
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Liu, Fangfang, Wenxin Cao, Qiqi Zhang, Yao Li, Heng Zhou, and Yingxiu Wan. "Winter Wheat Vernalization Alleles and Freezing Tolerance at the Seedling and Jointing Stages." Plants 14, no. 9 (2025): 1350. https://doi.org/10.3390/plants14091350.
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This study explores the relationship between allelic variation of the vernalization genes (VRN) and the freezing tolerance at the seedling and jointing stages of winter wheat growth. It provides a basis for molecular marker development for freezing tolerance breeding of winter wheat. A total of 435 wheat accessions were used to identify and evaluate the freezing tolerance at the seedling stage using field tests, while 192 wheat accessions were used to evaluate the freezing tolerance at the jointing stage in climate chamber tests. The VRN genes of the wheat accessions were detected using allele-specific markers of the VRN-A1, VRN-B1, VRN-D1 and VRN-B3 loci, and the relationship between VRN genotype and freezing tolerance at the two developmental stages was tested. There were significant differences in freezing tolerance between the wheat accessions. Assessing the freezing tolerance of 52 wheat accessions at both the seedling and jointing stages revealed no significant correlation between tolerance at these two stages. The genotypic analysis found that Vrn-D1 was the most frequent dominant allele in winter wheat, while no accession contained the dominant alleles Vrn-A1 and Vrn-B3. Notably, freezing tolerance showed stage-specific genetic regulation; seedling-stage freezing tolerance strongly correlated with vernalization gene allelic combinations (p < 0.05), whereas jointing-stage freezing tolerance exhibited no such association. The presence of all recessive alleles vrn-A1, vrn-B1, vrn-D1 and vrn-B3 was required for strong seedling-stage freezing tolerance. The VRN-D1 marker was effective for screening freezing tolerance materials under the premise that vrn-A1 and vrn-B1 alleles are recessive at winter wheat seedling stage.
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Chang, L. S., A. F. Iezzoni, and G. Adams. "Excised-shoot Assay for Tolerance of Peach to Leucostoma persoonii." HortScience 24, no. 6 (1989): 1011–12. http://dx.doi.org/10.21273/hortsci.24.6.1011.
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Abstract Dormant, excised shoot segments from peach [Prunus persica (L.) Batsch.] seedlings previously identified as tolerant, intermediate, or susceptible to Leucostoma persoonii were evaluated for longitudinal canker necrotic length after incubation in contact with a culture of L. persoonii growing on clarified oatmeal agar. The differences in seedling canker necrotic lengths were significant and corresponded with field ratings of disease susceptibility. Seedling Yennoh 1-39 and NJ672017002 1-8 were the most tolerant, whereas Loring 14-20 and Elberta 8-25 were the most susceptible. The excised-shoot assay is sufficiently quick, reliable, and related to field disease reaction to be used as a screening procedure in the breeding of peach cultivars tolerant to L. persoonii.
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Augustine, Steven P., and Keith Reinhardt. "Differences in morphological and physiological plasticity in two species of first-year conifer seedlings exposed to drought result in distinct survivorship patterns." Tree Physiology 39, no. 8 (2019): 1446–60. http://dx.doi.org/10.1093/treephys/tpz048.
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Abstract First-year tree seedlings represent a critical demographic life stage, functioning as a bottleneck to forest regeneration. Knowledge of how mortality is related to whole-seedling carbon and water relations is deficient and is required to understand how forest compositions will be altered in future climatic conditions. We performed a greenhouse drought experiment using first-year seedlings of two common pine species found in the Intermountain West, USA. Gas exchange, biomass gain, allometry and xylem water potentials were compared between well-watered and droughted seedlings from emergence until drought-induced mortality. In both species, morphological adjustments to confer drought tolerance, such as increased leaf mass per unit area, were not observed in seedlings exposed to drought, and droughted seedlings maintained photosynthesis and whole-seedling carbon gain well into the experiment. Yet, there were important differences between species in terms of carbon budgets, physiological responses and mortality patterns. In Pinus ponderosa P. & C. Lawson, physiological acclimation to drought was much greater, evident through stronger stomatal regulation and increased water-use efficiency. Photosynthesis and carbon budgets in P. ponderosa were greater than in Pinus contorta Dougl. ex. Loud., and survival was 100% until critical hydraulic thresholds in leaf water content and seedling water potentials were crossed. In P. contorta, physiological adjustments to drought were less, and mortality occurred much sooner and well before injurious hydraulic thresholds were approached. First-year conifer seedlings appear canalized for a suite of functional traits that prioritize short-term carbon gain over long-term drought tolerance, suggesting that conifer seedling survival is linked with carbon limitations, even during drought, with survival in species having narrower carbon survival margins being more hampered by carbon limitations.
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Jennings, Paul H., and Ann Fitzpatrick. "Involvement of HSP Synthesis and Protease Inhibitors in Heat Shock-induced Cucumber Seedling Chilling Tolerance." HortScience 30, no. 4 (1995): 775F—775. http://dx.doi.org/10.21273/hortsci.30.4.775f.
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Heat shock induction of chilling tolerance in cucumber seedlings is not blocked by inhibitors of protein synthesis. Treatment of germinating seeds with cycloheximide and actinomycin-D, prior to heat shock and chilling, does not block the heat shock induction of chilling tolerance, while the inhibitors alone promote chilling tolerance of seedling roots. To test whether the heat shock effect might be acting on proteases, two protease inhibitors (bestatin and PMSF) were tested for their ability to induce chilling tolerance. Although PMSF slowed germination, it still provided protection against chilling, but bestatin was much more effective.
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Lorca, E. Agostina, Ana E. Ferreras, and Guillermo Funes. "Seed size and seedling ontogenetic stage as modulators of damage tolerance after simulated herbivory in a woody exotic species." Australian Journal of Botany 67, no. 2 (2019): 159. http://dx.doi.org/10.1071/bt18093.
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Herbivory is one of the most important threats that plants face during early stages of development. Previous studies have indicated that seed size and seedling ontogeny strongly influence the response to herbivory at the seedling stage. However, little is known about their interactive effect. We simulated herbivory on seedlings of the exotic Gleditsia triacanthos L. and evaluated the combined effects of seed size and ontogenetic stage at which herbivory occurred on tolerance to herbivory. A greenhouse experiment was performed, with three non-overlapping levels of seed size. Seedlings from each seed size were clipped at two ontogenetic stages (two and five leaves). After three weeks, seedling survival, height, leaf number and dry biomass were measured. Damaged seedlings were not able to reach the size of the undamaged ones. Seedlings from small seeds showed the lowest values in most of the growth variables. Seedlings cut at two-leaf stage showed a higher compensation capacity than those cut at five-leaf stage. Seedlings from large seeds cut at ontogenetic stage I showed the highest compensation capacity in most of the variables. Partly compensating herbivory at this stage may be an advantage for the expansion of this exotic species to new areas.
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V, Aparna, Lakshmi Prayaga, Sarada C, and Arti Guhe. "Evaluating thermotolerant sunflower genotypes with temperature induction response (TIR) technique." Environment Conservation Journal 25, no. 1 (2024): 175–83. http://dx.doi.org/10.36953/ecj.24062640.
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High temperature affects various physiological processes of the plant. Delayed sowing and changing climate both subject the crop to increasing temperatures during the crop growth period. There is a need to take on a technique to screen the wide number of genotypes for high-temperature tolerance. In the present study, a screening protocol was followed based on the principle of “acquired tolerance” in which 47 sunflower seedlings were exposed to sub-lethal heat stress to induce tolerance before subjecting to subsequent lethal stress and the second set were directly exposed to lethal stress. Significant variation was observed for the traits - survival percentage, total seedling length, and seedling weight. Tolerant inbreds were identified using Z distribution and PCA. Results suggested that TIR is a rapid and powerful technique that can be used to screen large number of germplasms to identify thermotolerant lines.
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Zhou, Xiangyu, Yu Zhang, Suohu Leng, et al. "Uniconazole and Adaptability of Transplantations by Enhancing the Competition Tolerance in a High Sowing Density of Rapeseed Blanket Seedlings." Agronomy 12, no. 11 (2022): 2637. http://dx.doi.org/10.3390/agronomy12112637.
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Having nursery rapeseed (Brassica napus L.) seedlings at a high density in a tray is an indispensable step to realizing mechanized transplanting for rapeseed. The reduction in seedling quality caused by high sowing density is one of the key factors affecting transplanting quality and yield. Uniconazole has been considered as a potential plant growth regulator to improve plant growth under diverse unfavorable circumstances. In two sowing densities (400 and 800 seeds per tray), an experiment was carried out between 2021 and 2022 to investigate the effects of uniconazole seed-coating treatments on pre-transplant and post-transplant seedling characteristics. The results demonstrate that uniconazole treatment can effectively reduce the high-density-induced reduction in seedling dry matter and leaf area, stem thinness, and stem and petiole overgrowth. Further evidence that uniconazole can improve seedling quality, enhance yield, and lessen yield loss due to high-density sowing was provided by yield at maturity. However, because of the uncontrolled growth during the late stage in the tray, the relative growth rate of seedlings after transplant in the transplant shock stage revealed that lower doses of uniconazole treatment have a negative effect on the seedling recovery. The results of principal coordinate analysis and partial correlation analysis proved that the yield and net assimilation rate were related to the improvement of seedling high-density tolerance by uniconazole treatment. Consequently, 500–750 mg L−1 uniconazole coating per 100 g of seeds in 5 mL is recommended by this study, considering the potential risk of seedling emergence and growth caused by an overdose of uniconazole treatment.
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Cheng, C., L. M. Pei, T. T. Yin, and K. W. Zhang. "Seed treatment with glycine betaine enhances tolerance of cotton to chilling stress." Journal of Agricultural Science 156, no. 3 (2018): 323–32. http://dx.doi.org/10.1017/s0021859618000278.
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AbstractChilling injury is an important natural stress that can threaten cotton production, especially at the sowing and seedling stages in early spring. It is therefore important for cotton production to improve chilling tolerance at these stages. The current work examines the potential for glycine betaine (GB) treatment of seeds to increase the chilling tolerance of cotton at the seedling stage. Germination under cold stress was increased significantly by GB treatment. Under low temperature, the leaves of seedlings from treated seeds exhibited a higher net photosynthetic rate (PN), higher antioxidant enzyme activity including superoxide dismutase, ascorbate peroxidase and catalase, lower hydrogen peroxide (H2O2) content and less damage to the cell membrane. Enzyme activity was correlated negatively with H2O2 content and degree of damage to the cell membrane but correlated positively with GB content. The experimental results suggested that although GB was only used to treat cotton seed, the beneficial effect caused by the preliminary treatment of GB could play a significant role during germination that persisted to at least the four-leaf seedling stage. Therefore, it is crucial that this method is employed in agricultural production to improve chilling resistance in the seedling stage by soaking the seeds in GB.
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Bodnaryk, R. P., and R. J. Lamb. "Influence of seed size in canola, Brassica napus L. and mustard, Sinapis alba L., on seedling resistance against flea beetles, Phyllotreta cruciferae (Goeze)." Canadian Journal of Plant Science 71, no. 2 (1991): 397–404. http://dx.doi.org/10.4141/cjps91-055.
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Seedlings of Brassica napus L. 'Westar' or Sinapis alba L. 'Ochre' grown from seeds of various size were offered to flea beetles, Phyllotreta cruciferae (Goeze) in feeding tests for damage assessment. The proportion of cotyledon area damaged in both species was highest for seedlings grown from small seeds in choice and no-choice feeding tests. The proportion of seedlings killed by flea beetle feeding was also highest in seedlings from small seeds, an effect that was especially pronounced at high beetle densities (10/seedling) where 100% of seedlings from small seeds of B. napus were killed compared to 28.3% of seedlings from big seeds. For S. alba, at 20 beetles/seedling, 45.4% of seedlings from small seeds were killed compared to only 9.1% of seedlings from big seeds. Seedlings grown from big seeds of S. alba tolerated low levels of damage caused by flea beetle feeding or by scissors. No evidence for tolerance was obtained for seedlings from small seeds of S. alba or for seedlings from big or small seeds of B. napus. "Big seeds" appears to be a desirable trait that enhances crucifer seedling resistance to flea beetle attack and results in increased seedling survival. Key words: Brassica napus 'Westar', Sinapis alba 'Ochre', Phyllotreta cruciferae, flea beetle, seed size, resistance
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Benítez-Malvido, Julieta, Miguel Martínez-Ramos, José Luis C. Camargo, and Isolde D. K. Ferraz. "Responses of seedling transplants to environmental variations in contrasting habitats of Central Amazonia." Journal of Tropical Ecology 21, no. 4 (2005): 397–406. http://dx.doi.org/10.1017/s0266467405002439.
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In the Central Amazon we investigated whether seedling performance (survival, and relative growth rates in height and leaf numbers) was affected by initial seedling size (height and leaf numbers) in habitats that varied in their degree of human disturbance: cattle pasture, young secondary forest, 1-ha forest fragment and old-growth forest. Additionally, effects of photosynthetically active radiation (PAR), litter standing crop (LSC) and insect herbivory were evaluated 12 mo after transplantation in seedlings from the native canopy trees Chrysophyllum pomiferum, Micropholis venulosa and Pouteria caimito. Seedling performance changed rank across the understorey environment depending on species. Seedlings of Chrysophyllum thrived in all conditions but under high PAR, Micropholis thrived only in intermediate light conditions, whereas Pouteria thrived under high PAR. Effects of initial seedling size, PAR and herbivory after 1 y were specific to species, whereas LSC had no effect on performance. Initially larger seedlings resulted in lower survival for Chrysophyllum and Pouteria. Herbivory affected seedling performance in all species. Negative effects of herbivory were intensified under low PAR. Overall, our results showed that, as seedlings, species of the same family and characteristic of old-growth forests respond differently to the environmental constraints present in contrasting human-disturbed conditions. Larger seedlings may not always present greater tolerance to physical and biotic mortality risks.
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Robbins, JoAnn, and Thomas M. Sjulin. "Selection for Virus Tolerance in Strawberry Seedlings in Relation to Virus Source and Plant Age." Journal of the American Society for Horticultural Science 113, no. 6 (1988): 924–27. http://dx.doi.org/10.21273/jashs.113.6.924.
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Abstract Strawberry (Fragaria × ananassa Duch.) seedlings were planted in a greenhouse at 3- to 4-week intervals and simultaneously inoculated at ages 80, 101, 129, or 157 days with either of two naturally occurring virus sources each of which contained a mottle, mild yellow edge, and crinkle virus complex. Inoculation by aphids with either virus source reduced vigor, petiole length, leaflet width, stolons per plant, and vegetative dry weight of plants in the greenhouse. The tendency of virus inoculation to reduce vigor and petiole length was inversely proportional to increasing seedling age. In the field, inoculated seedlings were also less vigorous than control seedlings. Virus source effects and seedling age interactions with virus source were not significant. Selection for virus tolerance, based on greenhouse vigor, petiole length or leaflet width measurements, increased the frequency of seedlings subsequently classified as virus-tolerant in the field in both 80- and 101-day-old seedlings. Selection based on greenhouse vigor or petiole length increased the frequency in 129-day-old seedlings. No greenhouse selection method evaluated was effective in 157-day-old seedlings.
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Safitri, Heni, Bambang Sapta Purwoko, Iswari Saraswati Dewi, and Sintho Wahyuning Ardie. "SALINITY TOLERANCE OF SEVERAL RICE GENOTYPES AT SEEDLING STAGE." Indonesian Journal of Agricultural Science 18, no. 2 (2018): 63. http://dx.doi.org/10.21082/ijas.v18n2.2017.p63-68.
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<p class="abstrakinggris">Salinity is one of the most serious problems in rice cultivation. Salinity drastically reduced plant growth and yield, especially at seedling stage. Several rice genotypes have been produced, but their tolerance to salinity has not yet been evaluated. The study aimed to evaluate salinity tolerance of rice genotypes at seedling stage. The glasshouse experiment was conducted at Cimanggu Experimental Station, Bogor, from April to May 2013. Thirteen rice genotypes and two check varieties, namely Pokkali (salt tolerant) and IR29 (salt sensitive) were tested at seedling stage. The experiment was arranged in a randomized complete block design with three replications and two factors, namely the levels of NaCl (0 and 120 mM) and 13 genotypes of rice. Rice seedlings were grown in the nutrient culture (hydroponic) supplemented with NaCl at different levels. The growth and salinity injury levels of the genotypes were recorded periodically. The results showed that salinity level of 120 mM NaCl reduced seedling growth of all rice genotypes, but the tolerant ones were survived after 14 days or until the sensitive check variety died. Based on the visual injury symptoms on the leaves, five genotypes, i.e. Dendang, Inpara 5, Inpari 29, IR77674-3B-8-2-2-14-4-AJY2, and IR81493-BBB-6-B- 2-1-2 were tolerant to 120 mM salinity level, while Inpara 4 was comparable to salt sensitive IR29. Hence, Inpara 4 could be used as a salinity sensitive genotype for future research of testing tolerant variety. Further evaluation is needed to confirm their salinity tolerance under field conditions. </p>
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García, M. R., G. P. Bernet, J. Puchades, I. Gómez, E. A. Carbonell, and M. J. Asins. "Reliable and easy screening technique for salt tolerance of citrus rootstocks under controlled environments." Australian Journal of Agricultural Research 53, no. 6 (2002): 653. http://dx.doi.org/10.1071/ar01071.
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Three salt tolerance experiments using 5 common citrus rootstocks were carried out to find a reliable and easy screening technique for salt tolerance in breeding programs. The experiments were: (1) in vitro seed culture where salt tolerance was mainly evaluated as germination percentage, (2) hydroponic culture of 2-month-old seedlings where salt tolerance was mainly evaluated as survival percentage, and (3) hydroponic culture of satsuma-rootstock combinations where salt tolerance was evaluated by leaf and fruit characters. Treatments were: 4 mm K2CO3 and 0-100 mm NaCl in Expt 1; 3.5 mm K2CO3 and 0-50 mm NaCl, with and without K2CO3, in Expt�2; and 25 mm NaCl in Expt 3. Volkamer lemon was the most salt-sensitive genotype during seed germination (Expt�1), whereas Troyer citrange was the most sensitive when used as rootstock of satsuma (Expt 3). For seedling survival (Expt 2), the trifoliate orange variety Flying dragon showed the highest survival percentage, and chloride content of satsuma leaves and fruit juice were high on this rootstock under salinity (Expt 3). Alkalinity (pH = 8.5) greatly affected seedling survival of Cleopatra mandarin and Volkamer lemon (Expt 2), probably due to major disturbances in seedling nutrition. Analysis of trait values for the rootstocks in the different saline treatments in both the in vitro germination and the seedling survival experiments revealed some significant changes compared with control conditions. Most of these changes were not consistent between genotypes, except for chloride concentration in both shoot ([Cl]s) and root ([Cl]r). The ordering of genotypes for salt tolerance found in the literature, which corresponds to the ordering as chloride excluders in our satsuma Expt 3, agrees with the inverse ordering of genotypes regarding the increment of both [Cl]s and the ratio [Cl]s/[Cl]r from control to low salinity, but does not agree with salt tolerance measured as a percentage of germination or seedling survival. The increments of both [Cl]s and the ratio [Cl]s/[Cl]r from control to low salinity are suggested as criteria for early selection of salt-tolerant citrus rootstocks. Three salt tolerance mechanisms have been observed: chloride exclusion, water saving, and accumulation of soluble solids. They all seem to be presented by Cleopatra mandarin when used as rootstock, supporting its utilisation as donor of salt tolerance in breeding programs of citrus rootstocks.
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Sun, Changwei, Jian Chen, Lanlan Wang, et al. "Thymol Deploys Multiple Antioxidative Systems to Suppress ROS Accumulation in Chinese Cabbage Seedlings under Saline Stress." Agronomy 14, no. 5 (2024): 1059. http://dx.doi.org/10.3390/agronomy14051059.
Full textAbstract:
Developing biostimulants is a promising approach for sustainable agriculture under a saline environment. Thymol is a plant-derived compound with a potential antioxidative capacity. However, little is known about whether and how the antioxidative property of thymol plays a role in inducing plant tolerance against abiotic stresses. Here, we find that thymol induces saline tolerance in Chinese cabbage seedlings via enhancing the antioxidative capacity. Treatment with NaCl (100 mM) decreased the seedling fresh weight by 59.9% as compared to a control. Thymol at 20 μM showed the greatest effect on promoting seedling growth under saline stress, with the seedling fresh weight being increased by 71.0% as compared to NaCl treatment. Thymol remarkably decreased the overaccumulation of ROS (hydrogen peroxide and a superoxide radical); cell membrane damage (evaluated by lipid oxidation, membrane integrity, and relative conductivity); and cell death in seedlings under saline stress. Thymol induced three antioxidative systems to lower the ROS level in salt-treated seedlings. First, thymol remarkably activated a set of antioxidative enzymes, such as SOD (superoxide dismutase), APX (ascorbate peroxidase), CAT (catalase), and POD (peroxidase). Second, thymol balanced the cellular redox status by increasing the ratio of AsA/DHA (ascorbic acid/dehydroascorbic acid) and GSH/GSSG (glutathione/oxidized glutathione). Third, thymol significantly enhanced the level-two kinds of antioxidants (total phenol and flavonoid). All of these physiological responses were observed in both the shoots and the roots. In sum, thymol deploys multiple antioxidative systems to help Chinese cabbage seedlings against saline stress. Such findings suggest that thymol has great potential to be developed as a novel biostimulant enhancing crop tolerance against saline stress.