Importance of over-dominance as the genetic basis of heterosis in rice

J Zhuang; Y Fan; J Wu; Y Xia; K Zheng

doi:10.1007/BF02879340

Importance of over-dominance as the genetic basis of heterosis in rice

Sci China C Life Sci. 2001 Jun;44(3):327-36. doi: 10.1007/BF02879340.

Authors

J Zhuang¹, Y Fan, J Wu, Y Xia, K Zheng

Affiliation

¹ National Center for Rice Improvement, China National Rice Research Institute, 310006, Hangzhou, China, cnrrib@public.fy.hz.zj.cn.

PMID: 18726413
DOI: 10.1007/BF02879340

Abstract

In populations derived from commercial hybrid rice combination Shanyou 10, F(1) heterosis and F(2) inbreeding depression were observed on grain yield (GYD) and number of panicles (NP). Using marker loci evenly distributed on the linkage map as fixing factors, the F(2) population was divided into sub-populations. In a large number of sub-populations, significant correlations were observed between heterozygosity and GYD, and between heterozygosity and NP. This was especially true in type III sub-populations in which the genotype of a fixing factor was heterozygotes. In type III sub-populations, 15 QTL for GYD and 13 QTL for NP were detected, of which the majority exhibited over-dominance effects for increasing the trait values. This study showed that over-dominance played an important role in the genetic control of heterosis in rice.