Off-campus UNL users: To download campus access dissertations, please use the following link to log into our proxy server with your NU ID and password. When you are done browsing please remember to return to this page and log out.
Non-UNL users: Please talk to your librarian about requesting this dissertation through interlibrary loan.
PROTEIN AND GRAIN YIELD INHERITANCE IN FOUR POPULATIONS OF HARD RED WINTER WHEAT (TRITICUM AESTIVUM L.)
Abstract
Grain-yield and grain-protein inheritance was investigated in crosses of six hard red winter wheat cultivars. Parents for these crosses consisted of four high-protein cultivars--Lancota Selection, Century II, 77Y10442, and 77Y10456; and two moderately low-protein cultivars--Newton and Bennett. Early-generation testing was carried out on the crosses of Newton/Lancota Selection and Lancota Selection/Century II. F(,1), F(,2), and backcrosses of these two crosses and their parents were planted in two separate field experiments. Early generations of the crosses of Bennett/77Y10442 and Lancota Selection/77Y10456 were evaluated in a similar fashion by Chaudhry (1982). Advanced generations (F(,3), F(,4), and F(,5)) of all four crosses also were evaluated in this study. Frequencies for grain-protein content, grain yield, number of grains per plant, 100-grain weight, number of spikes per plant, and number of grains per spike had normal distribution curves, suggesting quantitative inheritance for these traits. Heritability estimates for grain-protein content and grain yield, determined by the components of variance in the early generations and parent-offspring regressions in the advanced generations, were low and inconsistent in different generations. Heritability estimates were generally lower for grain yield than for grain-protein content. Both yield and protein expressions were under strong environmental influence. The mode of gene action varied in different crosses. Additive and additive x additive gene effects were significant in protein expression of Newton/Lancota Selection (low x high) crosses and additive gene effects had a major role in the protein expression of Lancota Selection/Century II (high x high) crosses. The modes of gene action and inconsistency in the heritability estimates suggest that several major and minor genes may be involved in protein expression in the crosses studied. Grain-protein content was negatively associated with grain yield but in varying magnitudes in different generations. The correlation coefficient for the highest negative association was -0.56 and the lowest was nearly zero. The major components of grain yield were number of grains per plant and number of spikes per plant.
Subject Area
Agronomy
Recommended Citation
GHARZAI, MOHAMMAD KARIM, "PROTEIN AND GRAIN YIELD INHERITANCE IN FOUR POPULATIONS OF HARD RED WINTER WHEAT (TRITICUM AESTIVUM L.)" (1984). ETD collection for University of Nebraska-Lincoln. AAI8503428.
https://digitalcommons.unl.edu/dissertations/AAI8503428