Effect of ecological environments on subspecies characteristics and economic traits in filial generations of cross between indica and japonica rice

Abstract

Two recombinant inbred lines (RILs) populations, RILSA derived from the cross between "Zhongyouzao8" (indica) and "Toyonihiki" (japonica) rice cultivars, and RILSB derived from the cross between "Qishanzhan" (indica) and "Akihikari" (japonica) rice cultivars, were grown in Liaoning and Sichuan Provinces, China to understand the effects of ecological environments on the subspecies characteristics and economic traits in filial generations of cross between indica and japonica. The results showed that both the subspecies characteristics and economic traits changed significantly. The effects of ecological environments on Cheng's index and six subspecies characteristics were different on the basis of populations or characteristics. The distribution of Cheng's index in RILSA was japonicalinous in Liaoning and Sichuan. The distribution of Cheng's index in RILSB approached to normal distribution in Liaoning, but it was japonicalinous in Sichuan. As a whole, the two populations were more japonicalious in Sichuan than in Liaoning. The panicle number, seed setting rate and per-thousand-grain weight were decreased significantly in Sichuan. The grain number per panicle showed no significant change. A significant positive correlation was found between Cheng's index and the economic traits, including six subspecies traits. It suggested that the reason that the filial generation of cross between indica and japonica in northern China showed japonicanous subspecies characteristics might be the artificial selection by breeders on the economic traits. In addition, indica-japonica differentiation and the relationship with ecological environments were discussed.

Effect of Environment and Genetic Recombination on Subspecies and Economic Trait Differentiation in the F2 and F3 Generations from indica-japonica Hybridization

“…KW was significantly and positively correlated with subspecies characteristics, with KW ordered from highest to lowest according to japonica>japonica-like>indica-like>indica. This result is consistent with the results of previous research (Xu et al 2008;Gu 2010). The correlations observed with SSR and GYP, on the other hand, differ from results of earlier studies.…”