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Full-Text Articles in Agronomy and Crop Sciences
Predicted Response To S1 Selection For Agronomic And Disease Resistance Traits In Two Sunflower Populations, Syed Sadaqat Mehdi
Predicted Response To S1 Selection For Agronomic And Disease Resistance Traits In Two Sunflower Populations, Syed Sadaqat Mehdi
Electronic Theses and Dissertations
Variances, heritabilities, genetic and phenotypic correlations, and predicted gains were computed for quantitative disease resistance and agronomic traits from pooled S1 family data of Gene Pool II and ND 761 Helianthus annuus L. populations. Broad-sense heritability estimates for all traits were significant in both populations. Observed genotypic correlation coefficients were larger than their corresponding estimates of phenotypic correlation coefficients. Significant positive genetic correlations between resistance to Alternaria blight and Septoria leaf spot; and non-significant genetic correlations between Sclerotinia wilt disease reaction and agronomic traits were observed in both populations. Resistance to Phoma black stem was not significantly correlated with resistance …
Growth And Development Of Oat (Avena Sativa L.) Cultivars In Response To Water Stress, Abdel-Fattah H. Belal
Growth And Development Of Oat (Avena Sativa L.) Cultivars In Response To Water Stress, Abdel-Fattah H. Belal
Electronic Theses and Dissertations
Water stress occurs frequently in the North Central Plains and causes significant reductions in plant growth, development and grain yield. These effects of water stress apparently are dependent on the ability of plants to adapt to less than optimal environments. Plant water potential is dynamic, changing not only with the soil water content and atmospheric conditions, but also with the stage of growth. When plant water potentials become limiting, various physiological processes associated with plant growth, development and final yield are affected. The reduction in productivity in semi- arid environments is directly related to the inability of crop plants to …
The Effect Of Soil Storage Methods And Soil Microbes On Carbofuran And Terbufos Degradation, Muriel Monteleone Runholt
The Effect Of Soil Storage Methods And Soil Microbes On Carbofuran And Terbufos Degradation, Muriel Monteleone Runholt
Electronic Theses and Dissertations
The purpose of this research was to determine optimal soil storage methods for soils used in carbofuran and terbufos degradation studies. The effect of soil microbes on degradation was also observed. An LD50 study, using 22 day old crickets (Acheta domestica), was undertaken to establish the appropriate LC dose for carbofuran in the soil storage studies. A carbofuran use history failure soil and a noninsecticide use history soil of the same type were collected from the SDSU experimental farm in Centerville, South Dakota. After initial degradation and microbial analysis, the soils were stored air-dried and with a moisture level …
Genetics Of Flower Abortion And Pod Type In Soybean, Krishna P. Sharma
Genetics Of Flower Abortion And Pod Type In Soybean, Krishna P. Sharma
Electronic Theses and Dissertations
Field studies were conducted in 1982, 1983 and 1984 in ten soybean (Glycine max (L.) Merrill) genotypes of maturity group 00 to III, to evaluate the effects of genotype and year on flower abortion (FA), flowers/raceme (FPR), raceme length (RL), pod types (PT), seeds/raceme (SPR), seed weight (SW), and yield/raceme (YPR). Reproductive efficiency index (REI) was calculated for parental genotypes and their segregating populations. The effects of main stem node position and raceme flower position on FA and PT were also studied. Genetic studies were on F2's of 13 crosses plus F3 and F4 generations of …
Atrazine And Cyanazine Interception And Retention On Crop Residue, Mark A. Wrucke
Atrazine And Cyanazine Interception And Retention On Crop Residue, Mark A. Wrucke
Electronic Theses and Dissertations
The effect of several variables on herbicide interception and retention by crop residue was investigated. Variables considered include residue type and amount, amount of rain, time of rainfall occurrence, and herbicide formulation. Experiments were conducted in the greenhouse using corn (Zea mays), soybean (glycine max), and wheat (Triticum aestivum) residue. Simulated rainfall was applied using a modified potsprayer. Herbicide concentration in washoff water was determined using the pyridine-alkali colorimeteric technique for chloro-s-triazine herbicides. As the percent ground cover increased, the amount of herbicide reaching the soil surface at application decreased. With normal residue levels attained in South Dakota, 60% or …
Modeling Of Soil Water Flow And Root Uptake, V. Rasiah
Modeling Of Soil Water Flow And Root Uptake, V. Rasiah
Electronic Theses and Dissertations
The soil water pressure head, h, versus soil water content, 9, and the hydraulic conductivity, K, versus θ, relationships appear as functional coefficients in the non-linear partial differential water flow model. Before the flow equation can be used to simulate the flow of water through soils, the h versus θ and K versus θ relationships must be established. This requires the estimation of the parameters that describe the h versus θ and K versus θ functional relationships. In-situ water retention and hydraulic conductivity measurements were determined from the knowledge of initial and boundary conditions and water content profiles during drainage. …
The Relationship Between Reciprocal Spring By Winter Wheat Crosses And The Contribution Of Their Parents To Hybrid Performance, George Warren Partelow
The Relationship Between Reciprocal Spring By Winter Wheat Crosses And The Contribution Of Their Parents To Hybrid Performance, George Warren Partelow
Electronic Theses and Dissertations
Five diverse spring and five diverse winter wheat cultivars were crossed in all possible spring by winter combinations including their reciprocals to determine whether agronomic differences in reciprocal spring by winter crosses occur, and to determine the relative contribution of spring and winter parents to general and specific combining ability. Traits examined in the F1 generation in this greenhouse study included: 1) grain yield (g/plant) 2) number of spikelets per spike 3) total kernel weight (g) per spike 4) number of kernels per spike 5) number of tillers per plant 6) weight (g) of 100 kernels 7) length (mm) of …
Technology And Economics Of Commercial Scale Ethanol Production From Fodder Beets, William Ray Gibbons
Technology And Economics Of Commercial Scale Ethanol Production From Fodder Beets, William Ray Gibbons
Electronic Theses and Dissertations
Fodder beets yield two to three times more fuel ethanol per hectare than corn. This increased productivity should reduce feedstock costs and, consequently, ethanol production costs. The major factor that has limited use of this crop is the lack of a proven technology to process fodder beets -- economically and energy efficiently -- to fuel ethanol on a commercial scale. Research reported herein rectifies this situation by examining the technical and economic feasibility of community scale fuel ethanol production from fodder beets using two novel, continuous fermentation systems solid-phase fermentation and diffusion fermentation. Laboratory scale, batch fermentation trials were first …