Quantitative genetic analysis of full-sib family recurrent selection in an F_2 maize population

摘要

Seven cycles of full-sib family recurrent selection were conducted in an source F_2 population derived from a cross of maize lines D145 and KW1292. The objective of this study was to evaluate the effects of selection on the population mean, genetic variance and inbreeding coefficient. A pseudo-factorial crossing scheme was used to generate 144 full-sib families in each cycle, which were evaluated in three locations from 1994 to 2003. The selection intensity was 25 %. Grain yield increased 9.7 % per cycle and dry matter content 1.7 % per cycle. Inbreeding coefficient increased from zero in the source population to 0.12 in cycle 7. Estimates of additive and dominance variance were significantly different from zero, except for dry matter content in cycle 3 and cycle 6. No significant decrease in additive and dominance variance could be shown for both traits after seven cycles of selection. The results indicate that full-sib family recurrent selection has been effective in increasing the per se performance of the population while maintaining the genetic variance.