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Inheritance of grain yield and yield contributing traits in sorghum and implications for breeding
Abstract
Plant breeders can make better decisions in breeding if they know the inheritance and genetic variability of traits. Moreover, since grain yield comes from a combination of contributing traits, indirect selection may provide a better alternative to improve yield. The objectives of the study were to elucidate the inheritance of grain yield, yield components and grain filling parameters in various sorghum populations, determine the effectiveness of indirect selection, and characterize the best breeding parents. Two experiments of generation means analyses were conducted; one involving 16 sorghum crosses and six generations (P1, P2, F1, F2, BC1, and BC2), and another involving one cross and seven generations (P1, P2, F1, F2, BCIF2, BC2F2, and F3 progeny). With few exceptions, gene action was predominantly dominant for grain yield (GYP), grain number per plant (GNP) and rate of grain filling (RGF), predominantly additive for 100-grain weight (GW), and variable for length of grain filling (LGF). In all F2 populations the largest genetic coefficients of variation (GCV) were observed for GNP (from 18.5% to 26.8%). In the F3 progeny the GCV's for GYP, GW and GNP were very similar ranging from 10.2% to 12.1%. Direct selection for yield resulted in more favorable estimated gains in all traits compared to indirect selection. Similar estimated gains for GYP were observed using direct selection or using an index involving selection for GYP, GW, and GNP or GYP, LGF, and RGF, therefore direct selection should be easier and equally efficient. The female Wheatland and the pollinator 17473R were good combiners for GW and the best for GYP. The pollinator 22830R was the best only for GW. Only the 17473R crosses had dominant effects for GW and generated simultaneous heterosis for both yield components. Line 17473R should be useful as a parent for hybrid breeding, while fine 22830R should impart the largest genetic variability for most traits in populations, especially for GW.
Subject Area
Genetics|Agronomy|Plant sciences
Recommended Citation
Pena-Ramos, Alfonso, "Inheritance of grain yield and yield contributing traits in sorghum and implications for breeding" (1999). ETD collection for University of Nebraska-Lincoln. AAI9936767.
https://digitalcommons.unl.edu/dissertations/AAI9936767