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1
Grant, C. A., and L. D. Bailey. "Fertility management in canola production." Canadian Journal of Plant Science 73, no. 3 (July 1, 1993): 651–70. http://dx.doi.org/10.4141/cjps93-087.
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A review of the world literature on canola, a type of oilseed rape with low glucosinolates and low erucic acid, indicated that canola is a heavy user of plant nutrients. Canola requires as much or more nitrogen than cereal crops. Although canola requires more P than cereal crops for optimum yield, it may require lower levels of P fertilizers, as it is very effective at utilizing both soil P and applied P. During growth, canola takes up large quantities of K, but only a small amount is removed in the seed, so canola appears to require less fertilizer K than cereals. Canola requires more S than do cereal crops and S deficiencies may severely restrict canola yield, particularly where high levels of N are applied. Micronutrient deficiencies in canola are not common, but may occur on specific soils. Increases in canola yield with application of B, Zn and Cu have been reported in field studies. Balanced nutrition of canola is important to ensure optimum seed yield and quality as well as the most economic response to applied fertilizer. Key words: Brassica campestris, Brassica napus, nitrogen, phosphorus, potassium, sulphur
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Hirazawa, Makoto, Kimiyoshi Kamada, and Takashi Sato. "Altruism, environmental externality and fertility." Environment and Development Economics 24, no. 3 (March 20, 2019): 317–38. http://dx.doi.org/10.1017/s1355770x19000068.
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AbstractWe investigate the interaction between environmental quality and fertility in an altruistic bequest model with pollution externalities created by the aggregate production. Despite the negative externality related to the endogenous childbearing decisions, parents may choose to have fewer children in the competitive economy than in the social optimum. To achieve optimality, positive taxes on childbearing are required even with an insufficient number of children, if the social discount factor equals the parents' degree of altruism. On the other hand, child allowances may constitute the optimal policy if the social discount factor exceeds the parents' degree of altruism.
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Wall, E., I. M. S. White, M. P. Coffey, and S. Brotherstone. "The relationship between fertility, rump and other type traits in Holstein Friesian cows." Proceedings of the British Society of Animal Science 2005 (2005): 53. http://dx.doi.org/10.1017/s1752756200009649.
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Cattle breeders, farmers and vets believe that the decline in fertility seen in recent years can be partially attributed to changes in rump angle with selection being for more angular cows. This suggests that animals with pin bones that sit above the hip bones (high rump angle) will have poorer fertility. Few studies have shown a significant relationship between fertility and rump traits. This study investigates the popular belief that high rump angle equates to poor fertility by examining the genetic and phenotypic correlation between rump angle and fertility traits. The relationship between rump angle and fertility was also examined to see if there was an intermediate optimum or threshold of rump angle for good/bad fertility. The correlation of other type traits (udder and composite traits) with fertility was also examined to see if they had potential to add information to the estimation of fertility breeding values.
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Thompson, Alan Bruce. "Fertility of crustal rocks during anatexis." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 87, no. 1-2 (1996): 1–10. http://dx.doi.org/10.1017/s0263593300006428.
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ABSTRACT:After many years of systematic experimental investigations, it is now possible to quantify the conditions for optimum fertility to melt production of most common crustal rock types as functions of temperature and to about 30 kbar pressure. Quartzo-feldspathic melting produces steady increases in melt proportion with increasing temperature. The exact melt fraction depends on the mineral mode relative to quartz-feldspar eutectics and the temperatures of mica dehydration melting reactions. Mica melting consumes SiO2 from residual quartz during the formation of refractory Al2SiO5, orthopyroxene, garnet or cordierite.A simple graphical interpretation of experimental results allows a deduction of the proportions of mica and feldspar leading to optimum fertility. In effect, the mica dehydration melting reactions, at specific pressure and are superimposed on quartz-feldspar melting relations projected onto Ab-An-Or. Fertility to melt production varies with the mica to feldspar ratio and pressure. Pelites are more fertile than psammites at low pressures (e.g. 5 kbar), especially if they contain An40 to An50 plagioclase. At higher pressure (e.g. 10-20 kbar) and for rocks containing albitic plagioclase, psammites are more fertile than pelites. For a typical pelite (e.g. with An25 at 20 kbar), the cotectic with muscovite lies at higher (≍·) and XAb (≍0·42) than with biotite :≍0·35; XAb(≍·), thus dehydration melting of muscovite requires 10% more plagioclase for fertility than does biotite.The first melts from dehydration melting of muscovite (with Plg + Qtz) are more sodic and form at lower temperatures than the first melts from Bio + Plg + Qtz. With increasing pressure, to at least 30 kbar, granite minimum and mica dehydration melts become more sodic. This indicates that of such melts is greater than 0·3.
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Johnson, Charles D., and Dennis R. Decoteau. "Nitrogen and Potassium Fertility Affects Jalapeño Pepper Plant Growth, Pod Yield, and Pungency." HortScience 31, no. 7 (December 1996): 1119–23. http://dx.doi.org/10.21273/hortsci.31.7.1119.
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The influence of N and K rates in Hoagland's nutrient solution on Jalapeño pepper (Capsicum annuum L.) plant growth and pod production was determined on greenhouse-grown plants in sand culture. Varying the rates of N (1 to 30 mm) and K (1 to 12 mm) in Hoagland's solution identified optimum concentrations for Jalapeño plant growth and pod production. Two experiments were conducted to determine Jalapeño pepper sensitivity to differential fertilization. In the experiment seeded in April, nutrient treatments began at transplanting, and in the one seeded in May, treatments began after all plants had flower buds and half had flowered. Biomass and pod production per plant responded curvilinearly to N rate in both experiments. Optimum N rate for pod yield was 15 mm. Nitrogen rate affected pungency of pods only in the first experiment, with 1 mm N reducing capsaicin levels in fruit compared to other N rates. Biomass, fruit count, and fruit weight per plant increased linearly with increasing K rate in the first experiment and curvilinearly with K rate in the second experiment. The optimum K rate for pod yield was 6 mm. Potassium rates did not affect pod pungency. Jalapeño peppers grown in sand culture required 15 mm N and at least 3 mm K for optimum pod production.
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TOURNEMAINE, FREDERIC, and CHRISTOPHER TSOUKIS. "STATUS, FERTILITY, GROWTH AND THE GREAT TRANSITION." Singapore Economic Review 55, no. 03 (September 2010): 553–74. http://dx.doi.org/10.1142/s0217590810003894.
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We develop an overlapping generation model to examine how the relationship between status concerns, fertility and education affect growth performances. Results are threefold. First, we show that stronger status motives heighten the desire of parents to have fewer but better educated children, which may foster economic development. Second, the government should sometimes postpone the introduction of an economic policy in order to maintain the process of economic development, although such a policy aims to implement the social optimum. Third, status can alter the dynamic path of the economy and help to explain the facts about fertility during the great transition.
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Nanyanzi, Mary, Elizabeth Balyejusa Kizito, Michael Masanza, Godfrey Sseruwu, and Moses Makoma Tenywa. "Effect of Different Rates of Poultry Manure and Bio-Slurry on the Yield of Solanum aethiopicum Shum." Journal of Agricultural Science 10, no. 4 (March 5, 2018): 158. http://dx.doi.org/10.5539/jas.v10n4p158.
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Poor soil fertility remains the major cause of low crop productivity on smallholder farms that are engaging in vegetable production in sub-Saharan Africa. Appropriate soil fertility regimes are therefore critical for improving crop productivity. Its yield has remained low mainly due to poor soil fertility. A field experiment in two different seasons was planted in a Completely Randomized Block Design using Solanum aethiopicum Shum (Nakati). The treatments were 3 sole fertilizer options applied at the following rates: poultry manure and bio-slurry manure at 5, 10, 15, 20, 25 and 30 t ha-1, NPK (25:5:5) at the recommend application rate for tomato which is a sister crop and a control without any fertilizer. Crop budgets were used to determine the economic optimum rates of both sole applications of manure and combinations of manure with NPK. The sole applications and showed significantly (p ≤ 0.05) increased the yield of S. aethiopicum compared with the control. The established biological optimum rates were at 24.19 t ha-1 and 21.51 t ha-1 for poultry manure and bio-slurry respectively. Using the crop budgets it was concluded that the established economic optimum rates were 20 t ha-1 and 10 t ha-1 for sole poultry manure and bio-slurry respectively. Recommendations for use of sole poultry manure and bio- slurry at the rate of 20 t ha-1 and 10 t ha-1 respectively were made.
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Hayashikawa, Shuji, and Ken Takesaki. "An estimate of optimum timing for control of alfalfa weevil fertility." Kyushu Plant Protection Research 58 (2012): 100–103. http://dx.doi.org/10.4241/kyubyochu.58.100.
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Stott, A. W., R. F. Veerkamp, and T. R. Wassell. "The economics of fertility in the dairy herd." Animal Science 68, no. 1 (February 1999): 49–57. http://dx.doi.org/10.1017/s1357729800050074.
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AbstractA method to establish the economic optimum (minimum) cost of fertility in the dairy herd is described and demonstrated. A Markov chain model is used iteratively to establish the gross margin of the herd in the long term at various levels of oestrous detection rate and under two different rebreeding strategies. These gross margins are required by the optimization methodology. Under the initial assumptions reflecting current commercial practice in the United Kingdom, gross margin was £806 per cow. This figure varied by proportionately 0·15 over the range of oestrous detection rates assumed (0·4 to 0·7) while delaying rebreeding by 20 days caused gross margin to drop by approximately 0·04. It was concluded that it is important to optimize fertility control as well as rebreeding strategy in order to establish the economic impact of fertility in the dairy herd.The economic value of fertility was also expressed per unit of calving interval and adjusted calving interval (ACI). ACI was calculated by dividing calving interval by the proportion of cows not culled for reproductive failure. Under the assumptions made, the marginal value of calving interval at the optimum oestrous detection rate was £6·22 per day, rising to £7·44 per day if rebreeding was delayed. The corresponding figures for ACI were £1·57 per day and £1·24 per day. The range in marginal values at sub-optimal oestrous detection rates were £4·38 for calving interval and £0·61 for ACI. It was concluded that the lower variation in ACI at different levels of fertility may make it a more representative trait for inclusion in a selection index provided the necessary genetic parameters can be reliably estimated.
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Bratte, L., and S. N. Ibe. "Optimal insemination interval, semen dose and dilution for optimum fertility in chickens under humid tropical conditions." Animal Reproduction Science 20, no. 3 (September 1989): 179–85. http://dx.doi.org/10.1016/0378-4320(89)90083-3.
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Ranjbar Aghdam, H., Y. Fathipour, and D. C. Kontodimas. "Evaluation of non-linear models to describe development and fertility of codling moth at constant temperatures." ENTOMOLOGIA HELLENICA 20, no. 1 (June 1, 2017): 3. http://dx.doi.org/10.12681/eh.11501.
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Developmental rate of immature stages and age-specific fertility of females of codling moth at constant temperatures was modeled using non-linear models. The equations of Enkegaard, Analytis, and Bieri 1 and 2 were evaluated based on the value of adjusted R2 (R2adj) and Akaike information criterion (AIC) besides coefficient of determination (R2) and residual sum of squares (RSS). All models have goodness of fit to data especially for development [R2, R2adj, RSS and AIC ranged 0.9673-0.9917, 0.8601-0.9861, 0.08-6.7x10-4 and (-75.29) – (-46.26) respectively]. Optimum temperature (Topt) and upper threshold (Tmax) were calculated accurately (Topt and Tmax ranged 29.9-31.2oC and 35.9-36.7oC) by all models. Lower temperature threshold (Tmin) was calculated accurately by Bieri-1 model (9,9-10,8oC) whereas Analytis model (7,0-8,4oC) underestimated it. As far as fertility is concerned the respective values were better fitted near the optimum temperature (in 30oC) [R2 ,R2adj, RSS and AIC ranged 0,6966-0,7744, 0,5756-0,6455, 2,44-3,33 x10-4 and (-9,15)-7,15 respectively].
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Hag Husein, Hussam, Bernhard Lucke, Rupert Bäumler, and Wahib Sahwan. "A Contribution to Soil Fertility Assessment for Arid and Semi-Arid Lands." Soil Systems 5, no. 3 (August 4, 2021): 42. http://dx.doi.org/10.3390/soilsystems5030042.
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Soil fertility must be viewed as a dynamic concept that involves the constant cycling of nutrients between organic and inorganic forms. In this context, it refers also to supply adequate amounts of water and aeration for plant growth. Soil fertility under arid and semi-arid lands is constrained not only by limited water availability but also by small organic matter contents. Most fertility assessment systems are based on organic matter contents as the main parameter. However, crop experiments from various irrigated arid and semi-arid soils indicate that productivity is less-affected by organic matter contents than assumed. Therefore, we propose a new soil fertility system for dryland soils. It is a rule-based set of algorithms, mainly using additions and subtractions. Soil, climate, and landscape factors are integrated to calculate the numerical value of fertility for a given soil. We expect the system, which is focused on soil properties that keep or increase optimum soil moisture (such as texture), to be applicable in arid and semi-arid lands and to provide more realistic estimates of fertility regarding agricultural purposes. The manuscript will provide an outline of the main aspects of the system, illustrated by various case applications.
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Lazuardi, Andika, Syahril Nedi, and Sofyan Husein Siregar. "FERTILITY ANALYSIS OF BUNGUS TELUK KABUNG WATERS BASED ON THE CONCENTRATIONS OF NITRATE, PHOSPHATE, AND THE ABUNDANCE OF PHYTOPLANKTON." Asian Journal of Aquatic Sciences 5, no. 1 (April 2, 2022): 26–33. http://dx.doi.org/10.31258/ajoas.5.1.26-33.
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Water fertility is the capacity or ability of waters to provide suitable nutrients for the life of phytoplankton so that it can produce optimum production. This research was conducted on June 2021 in the Waters of Bungus Teluk Kabung, Padang, West Sumatra. The purpose of this study was to determine the fertility level of Bungus Teluk Kabung waters based on the concentration of nitrate, phosphate, and the abundance of phytoplankton. The results of this study show that the fertility rate of Bungus Teluk Kabung waters based on the value of nitrate concentration, phosphate, and phytoplankton abundance in the waters of Bungus Teluk Kabung, Padang, West Sumatra, belongs to the category of waters with low fertility levels (Oligotrophic) to moderate fertility levels (Mesotrophic). The concentration of nitrate and phosphate has a weak relationship with the abundance of phytoplankton in the waters of Bungus Teluk Kabung and there isn’t any significant effect between the concentration of nitrate and phosphate with the abundance of phytoplankton in the waters of Bungus Teluk Kabung, Padang, West Sumatra
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Saba, Tahseen, Wanlin Liu, Jingyan Wang, Fariha Saleem, Xikun Kang, Wenkai Hui, Wei Gong, and Hebiao Li. "Effects of organic supplementation to reduced rates of chemical fertilization on soil fertility of Zanthoxylum armatum." Dendrobiology 87 (May 25, 2022): 123–36. http://dx.doi.org/10.12657/denbio.087.009.
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Soil acidification, fertility depletion, food insecurity, and environmental pollution all are consequences of the extensive use of chemical fertilizers (CF) in intensively managed plantations. Recent studies have shown that incorporating organic manure (OM) to partially replace CF can help to maintain productivity and soil health. There are no reports on integrated fertilizer management of Zanthoxylum armatum, for optimal ecological services and economic profitability. A pot experiment with Z. armatum was performed to investigate the possibility of incorporating OM in reducing CF use, enhancing soil fertility, and increasing plant growth. For this, seven treatments were designed: NPK, PK, NP, NK, OM, MNPK (50%NPK+50%OM), and control (CK, no fertilizer application). The results showed that NPK application significantly (P < 0.05) increased plant growth, soil nitrate-N, ammonium-N and available K compared to CK. However conventional CF application induced soil acidification. OM application raised the soil pH from 5.50 (CK) to 6.58 and significantly enhanced soil fertility by increasing alkali-hydrolysable N (2.3 times), ammonium-N (1.4 times), available P (4.3 times), the activity of invertase (1.5 times), catalase (2.8 times), acid phosphatase (1.5 times), and count of soil culturable microbes (2.9 times) compared to CK. Conversely, sole OM application did not result in optimum plant growth. Integrating OM with NPK (MNPK), on the other hand, not only provided the highest growth comprehensive value (0.84), but also substantially higher soil fertility comprehensive value (0.71) than traditional CF treatments. Correlation analysis also indicated a positive and significant correlation between soil microbes, enzyme activities and available nutrients. Therefore, OM+NPK could be an optimum measure to get maximum benefits regarding soil fertility, growth of Z. armatum, fertilizer savings and sustainable agroecology.
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Mandal, Anuj Kumar, Pankaj Kumar Yadav, and Krishna Hari Dhakal. "COMPARATIVE STUDY OF EVALUATION OF SOIL FERTILITY STATUS IN RICE ZONE, MORANG." Tropical Agroecosystems 2, no. 1 (November 13, 2020): 12–25. http://dx.doi.org/10.26480/taec.01.2021.12.25.
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A study was conducted in the rice zone of Morang district to examine soil fertility status and the most limiting nutrient in the research area in accordance with rice cultivation requirements. Hundred samples were collected from two different locations of Ratuwamai Municipality ward number 6 and 8 at depth of 0-15 cm from surface soil. Samples were analyzed to find texture, pH, Nitrogen, Phosphorus, Potassium and Soil Organic Matter (SOM). Statistical tools were used to analyze the data. The most limiting nutrient in rice fields were determined by comparing the observed value with the standard requirement for rice fields. From analysis, it was revealed that, nitrogen content was found medium. Phosphorus was low in ward 6 whereas medium in ward 8. Potassium was high in ward 8 whereas medium in ward 6. SOM was low due to less application of organic fertilizer. Majority sample were of acidic probably due to more use of urea. Thirty percent samples of ward 8 were neutral and with equal alkalinity in both wards. Majority of sample was sandy loam except in ward 8 where ten percent sample was clayey loam. Both wards show equal behavior of loamy soil. Nutshell, majority of samples were of low fertility. Nitrogen and Potassium was most limiting as per the rice cultivation requirement with optimum soil pH. Various extension works regarding the importance of soil fertility management, sustainable soil management, optimum application of organic and inorganic fertilizers and the techniques to enhance the soil fertility status is required.
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Medvedev, V. "Soil Spatial Heterogeneity and Systems of Agriculture." Agricultural Science and Practice 2, no. 1 (April 15, 2015): 50–59. http://dx.doi.org/10.15407/agrisp2.01.050.
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Aim. To consider soil continuality and discreteness as features of heterogeneity manifestation in a soil cover, important for construction of agriculture systems. Methods. Geostatistical research of soil spatial heterogeneity, revealing the contours of a fi eld with various parameters of fertility. Results. The use of principles of precise agriculture and inspection of indicative properties of fi eld soils using a regular grid allowed to divide a fi eld into contours with three levels of fertility: the fi rst one is characterized by optimal or close to optimum properties which allows refusing from (or reducing substantially) tillage, introduction of fertilizers or chemical ameliorates; the second one has average parameters of fertility corresponding to zonal soils and demands the application of zonal technologies; the third one (with the worst parameters of fertility) presupposes regular use of the improved technologies. Conclusions. The introduction of precise agriculture will allow replacing a traditional zonal system with thenew which is soil-protecting and resource-saving one.
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Shi, Xue Yi, Yun Ping Wang, and Xiao Dan Sun. "Quality of Soils on Reclaimed Land from a Coal Mining Area." Advanced Materials Research 610-613 (December 2012): 2974–79. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.2974.
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Paper provides the results of research to determine the optimum technique of soil quality analysis in reclaimed land areas. The method involves topsoil stripping and mixed replacement techniques. The soils are sampled in different years after placement. Soil properties were analyzed. The data comes from the Wu-yang mine, Shanxi Province, China. Research has resulted in four conclusions: i) by topsoil stripping, soil fertility is nearly the same as the original soil, soil nutrients are higher in the tilth layer than in the bottom soil, and there is an upward tendency. ii) by mixed pushing, soil fertility is low and heterogeneous and needs to improve fertility. iii) changes of soil heavy metal concentrations are affected by dust and sewage and have little connection with reclaimed techniques and years after reclamation. iv) reclamation by topsoil stripping is better in the plain areas. Paper discusses how to choose the best reclamation technique and decide on the recovery time of land fertility.
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Guttieri, Mary J., Katherine O’Brien, Cecile Becker, Jeffrey C. Stark, Juliet Windes, and Edward Souza. "Managing nitrogen fertility of irrigated soft white spring wheats for optimum quality." Canadian Journal of Plant Science 86, no. 2 (May 5, 2006): 459–64. http://dx.doi.org/10.4141/p05-036.
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Irrigated wheat growers often choose to apply only part of the crop’s nitrogen fertilizer requirement at planting to avoid over-fertilizing the crop at early stages of growth. Later in the growing season, producers will apply additional nitrogen fertilizer as needed to optimize production. This study evaluated effects of top-dress nitrogen fertilizer application timing and rate on the milling and baking quality of two soft white spring wheat cultivars produced in an irrigated environment when the pre-plant fertility rates were insufficient for optimal crop yield. Top-dress N increased lactic acid solvent retention capacity (SRC), a measure of gluten strength, of the resulting flour by increasing flour protein concentration. Although lactic acid SRC response and the grain yield response to top-dress fertilizer were unaffected by application timing, other quality parameters, including break flour yield, flour ash, and, in the case of the cultivar Alturas, sugar snap cookie diameter, were affected by application timing. Earlier timing of top-dress fertilization minimized the detrimental effects of the fertilizer application on break flour yield and flour ash concentration. Key words: Soft wheat, nitrogen, gluten, flour ash
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Kanayo, Ogujiuba, Ogujiuba Chinelo, and Appunni Sathiya Susuman. "Consumption and Population Dynamics in Nigeria: Analysis and Micro simulations using Fertility Rate Variants." Journal of Asian and African Studies 51, no. 6 (July 28, 2016): 700–717. http://dx.doi.org/10.1177/0021909614557294.
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This paper examines how changes in Fertility Rate Differentials affect household portfolio demand (expenditure on food, monetary transactions, goods and services and non-cash expenditure) in Nigeria. The paper disaggregated household portfolio into four categories and established a link between population dynamics (demographic variables) and household expenditure components using the Vector Error Correction Methodology. The estimated equations are used to project the pattern of the different components of household demand based on the optimum case population scenario. The results suggest that fertility dynamics in Nigeria can produce significant effects on the economy via the expenditure profiles of households.
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Kachanoski, R. G., and G. L. Fairchild. "Field scale fertilizer recommendations: The spatial scaling problem." Canadian Journal of Soil Science 76, no. 1 (February 1, 1996): 1–6. http://dx.doi.org/10.4141/cjss96-001.
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Soil fertility may vary considerably within a field. The effects of variable soil fertility on the relationships among average crop yield response, average soil test, and fertilizer applied evenly to a field have not been examined. This paper develops stochastic equations to describe the average yield gain on a field basis from the application of a single constant rate of fertilizer, in fields with variable soil fertility. The equations are solved numerically for the specific case of nitrogen fertilizer on corn (Zea mays L.) in Ontario, Canada. The results suggest that since the relationships among yield response, soil test, and applied fertilizer are non-linear, a single soil test calibration cannot exist for fields with different spatial variability. Soil test calibrations obtained from sites with low variability (for example small plots) will not hold for sites with higher variability (for example farm fields). Calibrations obtained from sites with low variability will under-predict the optimum economic fertilizer rate for sites with low variability will under-predict the optimum economic fertilizer rate for sites with high variability. The results do not invalidate soil test calibration relationships per se. The challenge is to combine these calibrations with additional knowledge about the spatial distribution and field-scale variability of soil test values in order to maximize economic benefit. Key words: Spatial variability, soil test, fertilizer recommendation, yield, corn, field scale
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Ganaie, M. Imran, Manzoor A. Wani, Aisha Dev, and Ishtiaq A. Mayer. "Appraisal Soil Quality in the Agrarian Society of Pir Panjal Himalayas." Alinteri Journal of Agriculture Sciences 36, no. 2 (July 15, 2021): 104–11. http://dx.doi.org/10.47059/alinteri/v36i2/ajas21121.
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Background: The present study pertains to appraise the soil fertility in the foot hills of Pir Panjal by measuring different physico-chemical parameters such as pH, electrical conductivity (EC), organic carbon (OC), nitrogen (N), phosphorus (P), and potassium (K) in the foothill of Himalayas. Study area with unique physiographic and socio-economic identities have attributed to the soil fertility. Methods: Soil tests were carried at Soil Testing Laboratory (STL), Department of Horticulture. Soil samples at 1-30 cm depth were collected from 10 sample sites selected through composite sampling. Samples were collected randomly keeping in mind the maximum areal coverage. From each site, three sub samples were taken from selected locations to have holistic view of the soil fertility. Conclusion: The study showed deficiency of N & K in all the soil samples, with little variations in other parameters. Sample sites adopting organic farming showed optimum soil fertility. In the study we concluded that practice of adapting organic fertilizers is suitable for maintaing soil fertility. Least perception in the use of different fertilizers (organic & inorganic) a potent cause in the soil deformities in the region.
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GUBBELS, G. H., and W. DEDIO. "EFFECT OF PLANT DENSITY AND SOIL FERTILITY ON OILSEED SUNFLOWER GENOTYPES." Canadian Journal of Plant Science 66, no. 3 (July 1, 1986): 521–27. http://dx.doi.org/10.4141/cjps86-071.
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Field experiments were conducted in the 1979 to 1982 seasons to determine the response of sunflower (Helianthus annuus L.) genotypes with different growth habits to different plant densities at two levels of soil fertility in the Morden, Manitoba area. Treatments included hybrids and an open-pollinated cultivar, no fertilizer and 250 kg ha−1 of 27-14-0 and plant densities of 30 000, 45 000, 60 000 and 75 000 plants ha−1. Hybrids and open-pollinated cultivar responded similarly to the fertility and plant density levels. An increase in plant density did not affect yield, but slightly delayed flowering time, increased plant height, test weight and oil concentration and decreased achene weight. A plant density of about 45 000 plants ha−1 was required to ensure optimum yield.Key words: Sunflower, Helianthus annuus L., plant density, soil fertility
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Çevik, Kerim Kürşat, Hasan Erdinç Koçer, and Mustafa Boğa. "Deep Learning Based Egg Fertility Detection." Veterinary Sciences 9, no. 10 (October 17, 2022): 574. http://dx.doi.org/10.3390/vetsci9100574.
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This study investigates the implementation of deep learning (DL) approaches to the fertile egg-recognition problem, based on incubator images. In this study, we aimed to classify chicken eggs according to both segmentation and fertility status with a Mask R-CNN-based approach. In this manner, images can be handled by a single DL model to successfully perform detection, classification and segmentation of fertile and infertile eggs. Two different test processes were used in this study. In the first test application, a data set containing five fertile eggs was used. In the second, testing was carried out on the data set containing 18 fertile eggs. For evaluating this study, we used AP, one of the most important metrics for evaluating object detection and segmentation models in computer vision. When the results obtained were examined, the optimum threshold value (IoU) value was determined as 0.7. According to the IoU of 0.7, it was observed that all fertile eggs in the incubator were determined correctly on the third day of both test periods. Considering the methods used and the ease of the designed system, it can be said that a very successful system has been designed according to the studies in the literature. In order to increase the segmentation performance, it is necessary to carry out an experimental study to improve the camera and lighting setup prepared for taking the images.
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Islam, M. Sh, MNH Mahmud, F. Rahman, and MA Saleque. "Farmers Participatory Site Specific Nutrient Management in Tidal Flooded Soil for High Yielding Aus Rice." Bangladesh Rice Journal 17, no. 1-2 (November 10, 2014): 1–6. http://dx.doi.org/10.3329/brj.v17i1-2.20838.
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Experiments were conducted in farmers fields at Bakergonj, Barisal and Kathaltoli, Potuakhali districts to develop site-specific nutrient management package for high yielding aus rice. The participating farmers delineated soil fertility as the most fertile (grade I), medium fertile (grade II) and the least fertile (grade III) soil. Omissions of N, P, and K were compared with added NPK fertilizers in different fertility grades. At Bakergonj, the NPK treat plots yielded 4.29, 4.36 and 2.09 t ha1 in soil grade I, II and III, respectively. Omission of N, P and K reduced grain yield by 0.76, 0.95 and 0.29 t ha-1 in grade I, 1.53, 0.87 and 1.25 t ha-1 in grade II and 0.64, 0 and 0.28 t ha-1 in grade III, respectively. At Kathaltoli, the grain yield (6.21 t ha1) in grade I was higher than grade II (5.58 t ha1) and grade III (5.11 t ha1). Omission of N, P and K reduced grain yield by 0.93, 0.18 and 0.09 t ha-1 in grade I, 1.30, 0.37 and 0.93 t ha-1 in grade II and 1.86, 1.30 and 1.30 t ha-1 in grade III, respectively. For Bakergonj, the calculated optimum doses of N were 34, 69 and 29 kg ha1, P were 4.0, 4.0 and 0.0 kg ha-1 and K were 7.0, 31.0 and 7.0 kg ha1 for fertility grade I, II and III, respectively. For Kathaltoli, the calculated optimum doses of N were 42, 59 and 84 kg ha1, P were 1.0, 2.0 and 5.0 kg ha-1 and K were 2.0, 23.0 and 33.0 kg ha1 for fertility grade I, II and III, respectively. The application of predicted fertilizer dose might increase rice yield in all fertility grades of soil in both the locations.DOI: http://dx.doi.org/10.3329/brj.v17i1-2.20838Bangladesh Rice j. 2013, 17(1&2): 1-6
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Reis, André Fróes de Borja, Adriano Stephan Nascente, Rodrigo Estevam Munhoz de Almeida, and Aloísio Freitas Chagas Júnior. "Growth and nutrient contents in lowland rice due to phosphorus and potassium fertilization." Pesquisa Agropecuária Tropical 48, no. 2 (April 2018): 98–108. http://dx.doi.org/10.1590/1983-40632018v4850666.
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ABSTRACT In order to reach an optimum and sustainable production, growers must know the fertilizing potassium (K) and phosphorous (P) application rates. The present study aimed to determine the rice development in response to combined rates of P and K, on Plinthaquults (380-400 g kg-1 of clay), under high and low fertility conditions, in the tropical lowland plain of the Araguaia river, Brazil. Three field experiments were performed, each one consisting of a completely randomized factorial block design, with three replications. Treatments included a combination of six K2O rates (0 kg ha-1, 30 kg ha-1, 60 kg ha-1, 90 kg ha-1, 120 kg ha-1 and 150 kg ha-1) with six P2O5 rates (0 kg ha-1, 30 kg ha-1, 60 kg ha-1, 90 kg ha-1, 120 kg ha-1 and 150 kg ha-1). No interaction effect between P and K rates was observed for the evaluated variables in any fertility level/year. Phosphorous application under low fertility conditions, as well as K under high fertility conditions, affect overall crop nutrition, tillering capacity, yield components and grain yield of lowland rice, though no effects were observed due to the P application in high fertility soils and K in low fertility soils. Under high fertility conditions, the grain yield increment rate due to the K application was 4.04 kg ha-1, whereas in the low fertility areas, such as recently cleared fields, a maximum yield of 7,161 kg ha-1 was achieved by applying 140 kg ha-1 of P.
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Thapa, Soni, Sara Rawal, and Sandesh Thapab. "EFFECTS OF INTEGRATED NUTRIENT MANAGEMENT PRACTICES ON VEGETATIVE GROWTH AND YIELD RELATED PARAMETERS OF SUNFLOWER: A REVIEW." Reviews In Food and Agriculture 3, no. 2 (January 6, 2022): 72–75. http://dx.doi.org/10.26480/rfna.02.2022.72.75.
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Sunflower is a day-neutral, short duration, drought, and salinity tolerant potential oilseed crop in the world. Although it is an important source of vegetable oil for human consumption, its production is not satisfactory worldwide due to declining soil fertility and poor Nutrient management practices over the years. To enhance the productivity of sunflower and soil fertility status, several research attempts have been made on fertility management. Recent studies have depicted that the balanced and integrated use of organic and inorganic fertilizers resulted in a significant increase in vegetative growth and Yield parameters of sunflower along with improvement in seed oil content and protein content. Along with breeding for improved nutrient conditions adoption of INM is also a sound methodology for those who are resource-poor farmers. Thus, this review addresses the various Integrated nutrient management practices that be the best strategy for the sustainable and optimum production of sunflowers.
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SRIVASTAVA, A. K. "Citrus nutrition: An Indian perspective." Annals of Plant and Soil Research 24, no. 1 (February 1, 2022): 1–15. http://dx.doi.org/10.47815/apsr.2021.10116.
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Diagnosis and management of nutrient constraints are the two important pillars of sound citrus fertilizer program, although its history in India is as old as cultivation of citrus. Of the different diagnostic tools (leaf nutrient standards, soil thresholds of soil available nutrients, metalloenzyme activity, inflorescence analysis, juice nutrient standards, xylem sap analysis); leaf and soil-based nutrient standards have established their superiority over rest of the diagnostic methods. Optimum leaf nutrients standards developed for different commercial cultivars in Indiahave further warranted the necessity of identifying nutrient constraints through cultivar specific diagnostics in order to inflict precision diagnosis. Similar observations were envisaged through optimum soil fertility limits suggested for Indian citrus cultivars, primarily governed by prevailing soil fertility constraints. Multi-location nutrient specific field response studies lacked heavily on the point of uniformity in yield and quality improvements when replicated at other locations. Site-specific nutrient management studies demonstrated soil type-based fertilization, suggesting the fertilizers to be tailored as per canopy size within an orchard to derive rationality in fertilizer use within an orchard. Fertigation has further reduced the optimum fertilizer requirement by 30-40%, in addition to microbial consortium-based integrated nutrient management saving 30% cut from conventional RDF. Many other significant advances have taken place to improve the fertilizer-use-efficiency e.g. sensor-based variable rate application, fertigation using magnetized irrigation, open field hydroponics and dual purpose microbially loaded substrate (organic manure) enriched with limited inorganic fertilizers collectively known as INM a plausible alternative.
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Findlater, R. C. F., W. Haresign, and R. M. Curnock. "Effect of timing of intrauterine insemination with frozen-thawed semen on conception rates in ewes." Proceedings of the British Society of Animal Production (1972) 1987 (March 1997): 27. http://dx.doi.org/10.1017/s0308229600034681.
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The widespread use of artificial insemination (AI) in the United Kingdom sheep industry has been limited by the poor conception rates obtained after cervical insemination of frozen-thawed semen. The major problem in this respect is the impairment of sperm transport through the cervix, particularly when AI is used in conjunction with oestrus synchronisation.Previous studies (Killeen and Caffery, 1982; Maxwell, 1984) have indicated that a laparo-scopic technique for intrauterine insemination in ewes may overcome such limitations. At the moment, however, sufficient data on the optimum time of insemination and sperm doses required to maximise fertility in British breeds are not available. The present study was conducted to establish the optimum time of intrauterine insemination using frozen-thawed semen.
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SRIVASTAVA, A. K. "Citrus nutrition: An Indian perspective." ANNALS OF PLANT AND SOIL RESEARCH 24, no. 1 (February 1, 2022): 1–15. http://dx.doi.org/10.47815/apsr.2022.10116.
Full textAbstract:
Diagnosis and management of nutrient constraints are the two important pillars of sound citrus fertilizer program, although its history in India is as old as cultivation of citrus. Of the different diagnostic tools (leaf nutrient standards, soil thresholds of soil available nutrients, metalloenzyme activity, inflorescence analysis, juice nutrient standards, xylem sap analysis); leaf and soil-based nutrient standards have established their superiority over the rest of the diagnostic methods. Optimum leaf nutrients standards developed for different commercial cultivars in India have further warranted the necessity of identifying nutrient constraints through cultivar specific diagnostics in order to inflict precision diagnosis. Similar observations were envisaged through optimum soil fertility limits suggested for Indian citrus cultivars, primarily governed by prevailing soil fertility constraints. Multi-location nutrient specific field response studies lacked heavily on the point of uniformity in yield and quality improvements when replicated at other locations. Site specific nutrient management studies demonstrated soil type-based fertilization, suggesting the fertilizers to be tailored as per canopy size within an orchard to derive rationality in fertilizer use within an orchard. Fertigation has further reduced the optimum fertilizer requirement by 30-40%, in addition to microbial consortium-based integrated nutrient management saving 30% cut from conventional RDF. Many other significant advances have taken place to improve the fertilizer-use-efficiency e.g. sensor-based variable rate application, fertigation using magnetized irrigation, open field hydroponics, and dual purpose microbially loaded substrate (organic manure) enriched with limited inorganic fertilizers collectively known as INM a plausible alternative.
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Sun, Lingwei, Mengqian He, Caifeng Wu, Shushan Zhang, Jianjun Dai, and Defu Zhang. "Beneficial Influence of Soybean Lecithin Nanoparticles on Rooster Frozen–Thawed Semen Quality and Fertility." Animals 11, no. 6 (June 13, 2021): 1769. http://dx.doi.org/10.3390/ani11061769.
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The present study aimed to investigate the impact of different concentrations (0%, 0.5%, 1.0%, 1.5%, and 2.0%) of nano-soybean lecithin (SL) in the extender on sperm quality, sperm motion characteristics, and fertility outcomes of post-thawed rooster semen. Adult Ross broiler breeder roosters (n = 20) were subjected to semen collections twice a week for three weeks. At each collection, semen samples were pooled and allocated into five treatments corresponding to different nano-SL concentrations (control, SL0.5, SL1.0, SL1.5, and SL2.0). Sperm parameters, including motility (collected using a computer-assisted sperm analysis system), plasma membrane and acrosome integrities, and mitochondrial activity were assessed. Sperm malondialdehyde (MDA) and antioxidant activities (total antioxidant capacity (TAC); superoxide dismutase (SOD); glutathione peroxidase (GPx)) were evaluated. The fertility and hatchability obtained with frozen–thawed rooster semen supplemented with the optimum nano-SL concentration were assessed after artificial insemination. The results showed that the addition of 1% nano-SL into the extender led to a higher semen motility in roosters, improved plasma membrane and acrosome integrities, and higher mitochondrial activity of post-thawed rooster semen in comparison to controls (p < 0.05). The MDA levels in the SL0.5 and SL1.0 groups were lower than the other groups (p < 0.05). TAC activities in SL0.5, SL1.0, and SL1.5 groups were significantly higher than those in the other groups (p < 0.05). It was observed that the concentration of SOD was higher in the SL1.0 group than in the other groups (p < 0.05). The activity of GPx was not influenced in any of the cases (p > 0.05). Moreover, the percentages of fertility and hatchability in the SL1.0 group were higher (56.36% and 58.06%) than those in the control group (42.72% and 40.43%). In summary, the addition of nano-SL to the extenders enhanced the post-thawed semen quality and fertility of roosters by reducing the level of oxidative stress. The optimum nano-SL concentration was 1.0%. These results may be beneficial for improving the efficacy of semen cryopreservation procedures in poultry breeding.
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Danso, I., S. A. Okyere, E. Larbi, F. Danso, and B. N. Nuertey. "Assessment of nutrients status of areas supporting optimum oil palm (Elaeis guineensis Jacq. L) cultivation in Ghana." Ghana Journal of Agricultural Science 54, no. 2 (December 20, 2019): 1–14. http://dx.doi.org/10.4314/gjas.v54i2.1.
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In Ghana, information on the fertility status to support oil palm growth and productivity and possible fertilizer recommendation is not common. The objective of this study was to assess the nutrition-related limitations to production of oil palm across areas climatically delineated as optimum for sustainable oil palm production. Based on Ghana Interim Soil Classification System, benchmark soils identified in these areas were: Temang (Lixisols), Akroso (Acrisol), Kokofu (Alisols), Basitia (Acrislos), Firam (Acrisols) and Nkwanta (Acrisols). Results indicated generally strongly acidic soil and exchangeable acidity values obtained were high and consistent with very acidic soil conditions. There were generally- high C: N ratios (>20) except some few sites, thus supplementary nitrogen is required to reduce C: N ratio and improve N availability. The Total Exchangeable Bases (TEB), Effective Cation Exchange Capacity (ECEC) and available P values were less than the optimum values for sustainable oil palm production. Both soil and foliar analysis indicated that soils in areas assessed have low soil fertility with relatively good soil physical conditions. It is recommended that instead of superphosphate fertilizer application, rock phosphate should be administered due to high acidity. Raising the low ECEC levels of the soil calls for composted empty fruit bunches incorporation.
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BHOGAL, A., A. D. ROCHFORD, and R. SYLVESTER-BRADLEY. "Net changes in soil and crop nitrogen in relation to the performance of winter wheat given wide-ranging annual nitrogen applications at Ropsley, UK." Journal of Agricultural Science 135, no. 2 (September 2000): 139–49. http://dx.doi.org/10.1017/s0021859699008035.
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The effects of eight rates of nitrogen (N) application (0–245 kg/ha) on the performance of winter wheat over five seasons (1991–1995) on a long-term field experiment (established 1978) at Ropsley (UK) are described. In each of the five seasons, N was withdrawn from replicate plots in order to study the residual effect of fertilizer. N applications in excess of 140 kg/ha left significant residues as soil mineral N (SMN) in the autumn which, despite some loss over-winter, had a significant effect on the yield and N offtake of the subsequent crop. The amount of N carried over was equivalent to 8–20% of the fertilizer N and was observed at N applications up to 40 kg/ha lower than the optimum rate (c. 200 kg/ha). Part of the unrecovered N was also considered to contribute to the long-term build-up of fertility at the site. The results suggest that restrictions on N use to below the optimum will reduce leachable N, but may have an impact on soil fertility and future crop productivity. In addition, the rate of N applied to preceding crops should be taken into account when formulating fertilizer advice on retentive soils.
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Alvarez, A., J. A. Morábito, and C. Schilardi. "Spatial Variation in the Water Footprint of Corn under Rainfed and Irrigated Conditions in Northeastern Argentina." Agrociencia 19, no. 3 (December 2015): 69. http://dx.doi.org/10.31285/agro.19.283.
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The water footprint of a crop shows the volume of evapotranspired water required to produce a given yield. The water footprint splits up into the green water footprint, which is the volume of rainwater consumed, and the blue water footprint, which refers to the volume of surface and ground water applied through irrigation. It is expressed as a water volume per unit of product. The project consists in calculating the green and blue water footprint value for corn in central and northeastern provinces of Argentina under three conditions: 1) rainfed farming, 2) irrigated agriculture, and 3) optimum irrigation and soil fertility conditions. Internationally accepted methodology and the AquaCrop model were used to simulate ETc and crop yield. Once the model was calibrated, crop production was modeled for a twenty-year period (1990-2010) for 10 meteorological stations located in Argentina's corn producing region. The following aspects were taken into consideration: climate, soils in each location, planting density, harvest index, water table depth and furrow irrigation. Simulated yield values were compared with those registered by local institutions. It was observed that by applying irrigation and increasing fertility the water footprint is reduced, and this is due to the increase in yield. The green water footprint represents 92% of the combined sum (green plus blue). The calculated mean water footprint (green plus blue) is 803 L kg-1 for rainfed farming, 602 L kg-1 for irrigated agriculture; and 488 L kg-1 for production under optimum irrigation and soil fertility conditions. The paper suggests a potential target value of the water footprint which producers could reach with proper water management and fertilization practices.
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Katharine, S. Praveena, M. Suguna Devakumari, and S. Sumaiya Parveen. "Integrated Plant Nutrition System in Cotton – An Approach Towards Climate Change Mitigation." Journal of University of Shanghai for Science and Technology 23, no. 10 (October 9, 2021): 413–18. http://dx.doi.org/10.51201/jusst/21/10754.
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Agriculture is both affected by climate change but also contributes to it. As a sector, agriculture must therefore both adapt to changes and offers options for mitigation ie reducing greenhouse gas emissions and store carbon. The objective of the study is to explore the optimum level of plant nutrient for sustaining the desired crop productivity in hybrid cotton through optimization of benefit from all possible resources of plant nutrients in an integrated manner and to mitigate the green house gas emission through the adoption of Integrated Plant Nutrition System. The experiment was carried out in three locations with different soil fertility status with special emphasis to nitrogen levels in the soils. The fertilizer doses were fixed based on the soil test values and fertility grouping / indexing by International soil fertility evaluation and improvement programme. As part of organics, FYM was applied at two different levels, and the fertilizers were reduced accordingly. The results proved that application of organic manure @ 12.5 t ha-1 along with the recommended doses of nutrients proved superior in seed cotton production as well reduced nitrous oxide emissions.
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Chaiwongsar, Suraphon, Allison K. Strohm, Joshua R. Roe, Roxana Y. Godiwalla, and Catherine W. M. Chan. "A cyclic nucleotide-gated channel is necessary for optimum fertility in high-calcium environments." New Phytologist 183, no. 1 (July 2009): 76–87. http://dx.doi.org/10.1111/j.1469-8137.2009.02833.x.
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Jagusiak, W., E. Ptak, A. Żarnecki, and A. Satoła. "The relationship between fertility and intermediate optimum type traits in Polish Holstein-Friesian cows." Journal of Animal and Feed Sciences 23, no. 1 (March 3, 2014): 23–28. http://dx.doi.org/10.22358/jafs/65712/2014.
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Sibbald, Rachel. "Cystic ovarian disease in female guinea pigs." Veterinary Nurse 10, no. 6 (July 2, 2019): 318–22. http://dx.doi.org/10.12968/vetn.2019.10.6.318.
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This article will look at cystic ovaries in female guinea pigs. Cystic ovaries can be functional or non-functional fluid filled cysts that usually develop spontaneously in the older sow. The presence of cysts usually reduces fertility and potentially causes serious uterine disease. Identifying common symptoms related to this condition can aid the veterinary nurse when performing clinical examinations. Species specific care is vital to securing optimum patient care and the chance of a good outcome.
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Cakmak, Dragan, Biljana Sikiric, Jelena Beloica, Snezana Belanovic-Simic, Veljko Perovic, Vesna Mrvic, and Elmira Saljnikov. "Soil acidification as a limiting factor to agricultural production in the municipality of Ljubovija." Bulletin of the Faculty of Forestry, no. 109 (2014): 49–62. http://dx.doi.org/10.2298/gsf1409049c.
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The process of soil acidification means, above all, a reduction of soil solution pH. It can be the result of slow, years-long natural process or considerably accelerated due to a combination of natural processes and anthropogenic influences. Acidification is a very important factor in the permanent degradation of the fertility of soil, as the most important and hardly renewable natural resource. Studies on soil susceptibility to the process of acidification were carried out in the Municipality of Ljubovija, using three methods. Defining of the degree of soil susceptibility to the process of acidification allows timely activities aimed at the reduction of overall soil acidity. Management of agricultural land, in isolated areas, must be focused on a balanced use of fertilizers and agrotechnical measures, using proper planting /crops to achieve the optimum use of resources and sustainable soil fertility.
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Pilaquinga, Fernanda, Sofía Cárdenas, Doris Vela, Eliza Jara, Jeroni Morey, José Luis Gutiérrez-Coronado, Alexis Debut, and María de las Nieves Piña. "Fertility and Iron Bioaccumulation in Drosophila melanogaster Fed with Magnetite Nanoparticles Using a Validated Method." Molecules 26, no. 9 (May 10, 2021): 2808. http://dx.doi.org/10.3390/molecules26092808.
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Research on nanomaterial exposure-related health risks is still quite limited; this includes standardizing methods for measuring metals in living organisms. Thus, this study validated an atomic absorption spectrophotometry method to determine fertility and bioaccumulated iron content in Drosophila melanogaster flies after feeding them magnetite nanoparticles (Fe3O4NPs) dosed in a culture medium (100, 250, 500, and 1000 mg kg−1). Some NPs were also coated with chitosan to compare iron assimilation. Considering both accuracy and precision, results showed the method was optimal for concentrations greater than 20 mg L−1. Recovery values were considered optimum within the 95–105% range. Regarding fertility, offspring for each coated and non-coated NPs concentration decreased in relation to the control group. Flies exposed to 100 mg L−1 of coated NPs presented the lowest fertility level and highest bioaccumulation factor. Despite an association between iron bioaccumulation and NPs concentration, the 500 mg L−1 dose of coated and non-coated NPs showed similar iron concentrations to those of the control group. Thus, Drosophila flies’ fertility decreased after NPs exposure, while iron bioaccumulation was related to NPs concentration and coating. We determined this method can overcome sample limitations and biological matrix-associated heterogeneity, thus allowing for bioaccumulated iron detection regardless of exposure to coated or non-coated magnetite NPs, meaning this protocol could be applicable with any type of iron NPs.
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Rakha, Bushra Allah, Muhammad Sajjad Ansari, Shamim Akhter, and Elisabeth Blesbois. "Cryoprotective Effect of Glycerol Concentrations on Indian Red Jungle Fowl (Gallus Gallus Murghi) Spermatozoa." Avian Biology Research 11, no. 2 (May 2018): 80–88. http://dx.doi.org/10.3184/175815618x15180876264262.
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Semen cryopreservation protocols for wild avian species need to be optimised in order to achieve optimum post-thaw sperm quality and fertility. The present study was designed to evaluate the cryoprotective effect of different glycerol concentrations (11%, 15% and 20%) on post-thaw quality, recovery rates, absolute livability index and fertility of Indian Red Jungle Fowl (Gallus gallus murghi) semen. Semen was collected from eight mature cocks and cryopreserved for storage at −196 °C. Frozen semen was thawed at 37 °C for 30 s and assessed for motility, plasma membrane integrity, viability and acrosome integrity at 0, 2 and 4 h incubation at 37 °C. Percentages of motility, plasma membrane integrity, viability and acrosome integrity were recorded higher (P<0.05) post-thaw at 0, 2 and 4 h at 37 °C with 20% glycerol compared to 15% and 11% glycerol. Likewise, recovery rates (%) of aforementioned parameters after cryopreservation and absolute livability index were observed highest (P<0.05) with 20% glycerol. By comparing values of R2 after multivariate regression analysis, least negative effects of hours of incubation were observed on semen quality in extenders with 20% glycerol followed by 15% and 11% glycerol. The fertility outcomes (number of fertile eggs, fertility [%], number of hatched chicks, percent hatch and hatchability of fertilised eggs) were recorded higher (P<0.05) with 20% glycerol followed by 15% and 11% glycerol. It is concluded that the concentration of 20% glycerol gives the best cryoprotection for quality and fertility of Indian Red Jungle Fowl semen.
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Cunliffe, K. V., A. C. Vecchies, E. S. Jones, G. A. Kearney, J. W. Forster, G. C. Spangenberg, and K. F. Smith. "Assessment of gene flow using tetraploid genotypes of perennial ryegrass (Lolium perenne L.)." Australian Journal of Agricultural Research 55, no. 4 (2004): 389. http://dx.doi.org/10.1071/ar03156.
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Ryegrass species are among the most important species in sown pastures, turf settings, and weed populations worldwide. Perennial ryegrass (Lolium perenne L.) is an outcrossing, wind-pollinated grass. Recent research has demonstrated the feasibility of developing transgenic perennial ryegrass varieties. In order to model the consequences of gene flow from transgenic grass genotypes in a field situation, the model non-transgenic trait of fertility among autotetraploid genotypes was chosen. Gene flow over distance and direction from a donor plot to surrounding sexually compatible recipient plants was studied. Reproductive isolation was achieved through the fertility barrier that arises between tetraploid and diploid ryegrass genotypes, despite the presence of diploid plants in a meadow situation. Fertility was used as an indication of effective gene flow over distance and direction. Measures of the fertility of recipient plants included total seed production (TSP), floret site utilisation (FSU), and relative fertility of recipient plants as a percentage of those within the donor plot (RF%). A leptokurtic distribution for gene flow was identified, with differences in the rate of decline over distance depending on direction. Simple sequence repeat (SSR) polymorphism was used to identify the paternity of progeny plants. The proportional representation of parents among the progeny was not significantly different from that expected due to the numerical representation of the different donor parent genotypes. The results of this research will have important implications for risk analysis prior to the field release of transgenic ryegrasses, fescues, and other pasture grass species, and for seed production in terms of cultivar purity and optimum isolation distance.
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Odion, Ehiabhi Cyril, Idris Salihu Ahmadu, Ahmed Rufai Aminu, Grace Lamba Luka, Shero Abdulazeaz Isah, and Uthman Lucky Arunah. "Determination of Production Efficiency of Crop Mixtures: the Relevance of the Agronomic Efficiency Method." Agricultura Tropica et Subtropica 48, no. 3-4 (December 1, 2015): 59–66. http://dx.doi.org/10.1515/ats-2015-0009.
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Abstract The paper looks at estimation of the agronomic efficiency (AE) for various crop mixtures at varying levels of fertility management. To evaluate the concept, three trials using different cropping patterns and fertility rates were reviewed by calculating and comparing the relative yield and agronomic efficiency of the main crop. AE was higher in the mixtures compared to the sole crop in all the trials, and in the mixtures while efficiency between the control and the fertility levels employed were high, those between the fertility levels were not as high and increased at a reducing rate, sometimes tending to be constant. These responses gave rise to situations similar to a quadratic response and could therefore permit for optimum fertility levels for crop mixtures to be predicted. This therefore means that sustainable intensification is possible under small scale production systems as increase in efficiency was higher at lower fertilizer rates compared to the higher rates. Assessment of AE for crop mixture could also result in staggered recommended production practices, thus discouraging the excessive use of fertilizers – chemical or organic – and cut cost of production, reduce the pollution of the environment with its attendant consequences while production costs could be within reach of the small scale farmers. Small scale family farmers seeking alternative methods of soil fertility management could be encouraged to undertake the clipping/thinning management of companion leguminous crops as such measures could enhance their productivity as the estimation of AE has shown in these investigations. The practice of either clipping or thinning of the leguminous companion crop is similar or close to current production practices employed by these farmers and therefore should not be difficult to adapt and adopt.
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Ahmed, Ahmed, Yvan Gariepy, and Vijaya Raghavan. "Influence of wood-derived biochar on the compactibility and strength of silt loam soil." International Agrophysics 31, no. 2 (April 25, 2017): 149–55. http://dx.doi.org/10.1515/intag-2016-0044.
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Abstract Biochar is proven to enhance soil fertility and increase crop productivity. Given that the influence of biochar on soil compaction remains unclear, selected physico-mechanical properties of soil amended with wood-derived biochar were assessed. For unamended silt loam, the bulk density, maximum bulk density, optimum moisture content, plastic limit, liquid limit, and plasticity index were 1.05 Mg m-3, 1.69 Mg m-3, 16.55, 17.1, 29.3, and 12.2%, respectively. The penetration resistance and shear strength of the unamended silt loam compacted in the standard compaction Proctor mold and at its optimum moisture content were 1800 kPa and 850 kPa, respectively. Results from amending the silt loam with 10% particle size ranges (0.5-212 μm) led to relative decreases of 18.1, 17.75, 66.66, and 97.4% in bulk density, maximum bulk density, penetration resistance, and shear strength, respectively; a 26.8% relative increase in optimum moisture content; along with absolute increases in plastic limit, liquid limit, and plasticity index of 5.3, 13.7, and 8.4%, respectively. While the biochar-amended silt loam soil was more susceptible to compaction, however, soil mechanical impedance enhanced.
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Guttieri, Mary J., Reuben McLean, Jeffrey C. Stark, and Edward Souza. "Managing Irrigation and Nitrogen Fertility of Hard Spring Wheats for Optimum Bread and Noodle Quality." Crop Science 45, no. 5 (September 2005): 2049–59. http://dx.doi.org/10.2135/cropsci2004.0756.
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Reyes Moreno, Giovanni, Aquiles Enrique Darghan Contreras, and Diego Andrés Ramírez Lesmes. "Design of a surface response model to determine the optimal value for wood volume in Acacia mangium Willd, by applying different doses of biochar to the soil." DYNA 86, no. 211 (October 1, 2019): 26–31. http://dx.doi.org/10.15446/dyna.v86n211.78331.
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The low fertility of soils of the eastern plains of Colombia makes it necessary to search for methods of improving different soil properties. Fertile soils increase yields of different crops in the region, and particularly agroforestry agroecosystems will increase wood volume. Including stabilized waste residues such as biochar will probably increase fertility. The objective of this research was to estimate the optimal volume of Acacia mangiumwood that can be obtained, when using two fertilizers applied to the soil at two levels, fitting a central composite design with star points. In the model, two levels of treatment were applied: 40 and 80 ton · ha-1of biochar and 50 and 100 g per plant ofsynthetic fertilizer 15-15-15. The optimum wood volume was found at 8566.9 cm3when the biochar was combined with 63.1 ton·ha-1and 15-15-15 at a dose of 84.4 g per plant.
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Sawa, A., and S. Krężel-Czopek. "Effect of first lactation milk yield on efficiency of cows in herds with different production levels." Archives Animal Breeding 52, no. 1 (October 10, 2009): 7–14. http://dx.doi.org/10.5194/aab-52-7-2009.
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Abstract. Lifetime performance was analysed in 6 981 Black and White cows with different proportion of Holstein Friesian inheritance from the active population in the Kujawsko- Pomorskie province according to first lactation yield. It was shown that from the viewpoint of lifetime efficiency, the optimum milk yield of first calvers depends on the milk yield level of the herd. In herds with ≤5 000 kg milk production, the best efficiency was shown by the cows that produced 6 001–7 000 kg milk as first calvers. A decrease in lifetime milk yield, reduced life span and length of productive life, and lower fertility should be taken into account for more efficient first calvers. In herds with 5 000–6 500 and >6 500 kg milk production, lifetime milk yield and milk yield per day of (productive) life increased with increased first lactation milk yield, while fertility deteriorated.
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Granberry, Darbie M., and William Terry Kelly. "IMPROVING QUALITY OF CONTAINER-GROWN PEPPER TRANSPLANTS THROUGH FERTILITY MANIPULATION." HortScience 30, no. 3 (June 1995): 428d—428. http://dx.doi.org/10.21273/hortsci.30.3.428d.
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During summer in southern Georgia, greenhouses often reach or exceed 49C. Subsequently, transplants grown in these houses tend to exceed optimum height. To determine effects of N and P fertility levels on pepper (Capsicum annuum) transplant growth, applications of nutrient solutions with 58, 12, and 0 ppm N and 114, 57, and 0 ppm P205 were applied to recently emerged Capistrano bell pepper beginning 12 Aug. 1994. Plants were grown in polystyrene flats using a commercial noncharged artificial soil mix. Nutrient solutions were applied as needed to maintain adequate moisture until 31 Aug., except for two treatments that received only water after 22 Aug. Data were taken on 22 and 31 Aug. With 58 ppm N, 0 P decreased plant height, leaf count, leaf area, and plant weight. Higher N increased plant height, ratings of intact root plugs and washed roots, stem diameter, leaf count, leaf area, and plant weight. At 12 ppm N, P had no significant effect on transplant growth. Withholding fertilizer the final week reduced plant height, ratings of intact root plugs, stem diameter, number of leaves, leaf area, and plant weight.
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Kościński, Krzysztof. "Fertility, offspring survival, and adaptive value as related to morphological traits – methodological and interpretation problems." Anthropological Review 63 (June 30, 2000): 103–18. http://dx.doi.org/10.18778/1898-6773.63.08.
Full textAbstract:
A great deal of research has been carried out in order to find a relationship between somatic traits and fertility, offspring survival rate and adaptive value. However, the results of these studies lack consistency. The reason behind these discrepancies is the use of inadequate statistical methods and the application of unreliable principles of interpretation. The purpose of this paper is to indicate the methods of data analysis and result interpretation, which permit optimum utilisation of the information contained in a given sample and make it possible to draw the correct conclusions.
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RAHMAN, OMAR, JANE MENKEN, and RANDALL KUHN. "The impact of family members on the self-reported health of older men and women in a rural area of Bangladesh." Ageing and Society 24, no. 6 (November 2004): 903–20. http://dx.doi.org/10.1017/s0144686x04002314.
Full textAbstract:
The purpose of this study is to examine whether the co-residence of spouses and children affects self-reported general health among older men and women in a rural area of Bangladesh. Binary logistic regression has been used to explore the impact of spouses and children on self-reported health, with particular attention to the gender of children and interactions with chronic disease. The data are from the Matlab Health and Socio-Economic Survey. A sample of 765 women and 979 men aged 60 or more years with at least one surviving child was available. The principal result is that for an older woman, optimum self-reported health is most likely when a spouse and at least one son and one daughter are present. Any deviation from this family pattern (either no spouse or children of only one sex) leads to a significantly increased risk of poor self-reported health. On the other hand, among older men there were no differences in self-reported health among the various spouse-child combinations. The relationship between a balanced gender distribution of children and optimum self-reported health among older women may explain the levelling out of fertility at roughly three children per women despite intensive family planning promotion in the area. Further reductions in fertility (an important policy concern) may depend on improving the substitutability of sons and daughters in the support of their elderly mothers.
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Diomandé, L. B., G. R. Soro, S. Soro, and Et Yao Kouamé A. "CHEMICAL SOIL FERTILITY DIAGNOSIS FOR COTTON CROPPING IN NORTHERN COTE D'IVOIRE." International Journal of Research -GRANTHAALAYAH 9, no. 8 (August 31, 2021): 27–34. http://dx.doi.org/10.29121/granthaalayah.v9.i8.2021.4130.
Full textAbstract:
The work was conducted in the north of Cote d’Ivoire, central pivot cotton production savannah area, to make the diagnosis of soil fertility for cotton cropping. Cotton cropping, the mainstay of the savannah's economy, suffered from low productivity in relation to the soils chemical properties. Prior cultivation, soils samples were collected at a depth of 0 to 30 cm, collecting 32 simple samples to generate a complete sample. The samples were sent to the soil laboratory to measure the pH unities, CEC, nitrogen, phosphorus, potassium, calcium, magnesium, sodium, iron, zinc, copper and manganese contents. In order to facilitate the interpretation of analysis results, the nutrients critical level recommended for optimum production of cotton were used. Results showed that soils had pH ranging from 4.4 to 6.4. On the other hand, the need to add nitrogen, magnesium and phosphorus to the soils and to augment the low carbon, calcium and potassium content. There is the need to search for fertilizer formulations with nitrogen, magnesium phosphorus and calcium for the Cote d'Ivoire cotton belt.