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Narrow Sense Heritability And Additive Genetic Correlations In Alfalfa Subsp. Falcata, Heathcliffe Riday, E. Charles Brummer
Narrow Sense Heritability And Additive Genetic Correlations In Alfalfa Subsp. Falcata, Heathcliffe Riday, E. Charles Brummer
Journal of the Iowa Academy of Science: JIAS
The complex genetics of autotetraploid alfalfa (Medicago sativa L.) make additive genetic variance component estimation difficult. Halfsib family variances often are used to estimate additive genetic variances and, by extension, narrow sense heritabilities and additive genetic correlations. These estimates contain a portion of the dominance variance. Using such calculations, in conjunction with parent-offspring covariance estimates, the dominance component can be separated from the additive genetic component. This is rarely done. This study reports average estimates across 30 populations, of both additive and dominance variance component estimates based on between halfsib family variance and parent-offspring covariance for biomass yield, plant height, …
Biomass Yield Stability In Alfalfa, Joseph G. Robins, Heathcliffe Riday, Sara J. Helland, E. Charles Brummer
Biomass Yield Stability In Alfalfa, Joseph G. Robins, Heathcliffe Riday, Sara J. Helland, E. Charles Brummer
Journal of the Iowa Academy of Science: JIAS
In addition to biomass production, alfalfa (Medicago sativa) cultivars also need to express yield stability across diverse environments. The objective of this experiment was to analyze the nature of biomass yield stability in ten commercial alfalfa cultivars by evaluating performance of individual genotypes. Biomass yield was measured in each of five environments across two years, and the yield stability computed for the overall cultivar mean performance and the mean performance of each of the genotypes comprising the cultivars using the genotype x environment variance statistic of Shukla and the superiority statistic of Lin and Binns'. The GxE variance of the …
Engineering Proteinase Inihibitor Genes For Plant Defense Against Predators, Clarence A. Ryan, Thomas Moloshok, Gregory Pearce, Gynhueng An, Robert W. Thornburg, Gerald Hall, Russell Johnson, Edward E. Farmer, Curtis Palm
Engineering Proteinase Inihibitor Genes For Plant Defense Against Predators, Clarence A. Ryan, Thomas Moloshok, Gregory Pearce, Gynhueng An, Robert W. Thornburg, Gerald Hall, Russell Johnson, Edward E. Farmer, Curtis Palm
Journal of the Iowa Academy of Science: JIAS
Small proteinaceous inhibitors (Mr<20,000) of the digestive serine proteinases of animals and microorganisms are found as moderately abundant proteins in storage organs and leaves of many plant genera. The proteins are powerful inhibitors of the digestive enzymes of plant predators and therefore are considered to be part of the array of defensive chemicals of plants. Proteinase inhibitor genes show excellent promise, using DNA technology, to manipulate plant genomes to express these biologically active proteins in order to improve natural defense systems. Members of two unrelated families of serine proteinase inhibitors found in tomato and potato plants, called Inhibitor I (monomer Mr 8000) and Inhibitor II (monomer Mr 12,300), are under both environmental and developmental regulation in different tissues of the plants. Genes coding for wound-inducible Inhibitors I and II have been isolated from both tomato and potato genomes and characterized. Tobacco plants have been transformed with the chimeric genes containing wound-inducible promoters fused with the reporter gene, chloramphenicol acetyl transferase, to assess promoter function and signal transmission. Transacting factors that regulate their expression in response to wounding are also being identified and purified. Intact genes are being employed to transform agriculturally important crop plants to determine their potential usefulness to enhance defensive capabilities of plants against herbivores and pathogens.