Broadening the Genetic Base of Chinese Maize Heterotic Pools with Exotic Germplasm. Issue 5 (1st September 2013) - Yong, Hongjun
ABSTRACT: Introgression of elite exotic maize ( Zea mays L.) germplasm into breeding programs would increase genetic variation within heterotic groups and counter the narrowing of the Chinese germplasm base. This study measured the performance of exotic populations in northern China to allow use of elite germplasm to broaden the genetic base of Chinese germplasm. Fifteen International Maize and Wheat Improvement Center (CIMMYT) and U.S. populations were testcrossed with Csyn 5, Cpop.11, and Cpop.12, which represent Chinese Sipingtou, Lancaster Sure crop, and Reid Yellow Dent subgroups, respectively. Forty‐five testcrosses and 18 populations were evaluated using Miranda Filho and Geraldi's analysis for variety effects and combining ability for grain yield, stalk lodging, ear height, and days to silking in northern China. The results indicated that additive genetic effects were more important than nonadditive genetic effects for all traits measured. Pop28 and BS29 were most adapted to northern China for grain yield and other adaptation traits, and Pool 26, Pop32, Tuxpeño, and Suwan 1 exhibited more favorable alleles for stalk lodging tolerance and high yield potential. We propose to introgress Pool 26 and Suwan 1 into Sipingtou, BS29 and Pop32 into Lancaster, and Pop28 and Tuxpeño into Reid to enrich the genetic base of Chinese heterotic pools.