63 Genetic dissection on the top three leaves in rice using progenies derived from an japonica-indica cross 

Changbin Yin#, Huihui Li#, Zhigang Zhao, Zhiquan Wang, Shijia Liu, Liangming Chen, Xi Liu, Yunlu Tian,
Juan Ma, Lidong Xu, Dashuang Zhang, Susong Zhu, Danting Li, Jianmin Wan and Jiankang Wang*.2017.Genetic dissection of top three leaf traits in rice using progenies from a japonica
indica cross.JIPB.doi: 10.1111

Abstract The size of the top three leaves of rice plants is strongly associated with yield; thus, it is important to consider quantitative traits representing leaf size (e.g., length and width) when breeding novel rice varieties. It is challenging to measure such traits on a large scale in the field, and little is known about the genetic factors that determine the size of the top three leaves. In the present study, a population of recombinant inbred lines (RILs) and reciprocal single chromosomal segment substitution lines (SSSLs) derived from the progeny of a japonica Asominori
indica IR24 cross were grown under four diverse environmental conditions. Six morphological traits associated with leaf size were measured, namely length and width of the flag, second and third leaves. In the RIL population, 49 QTLs were identified that clustered in 30 genomic region. Twenty-three of these QTLs were confirmed in the SSSL population. A comparison with previously reported genes/QTLs revealed eight novel genomic regions that contained uncharacterized ORFs associated with leaf size. The QTLs identified in this study can be used for markerassisted breeding and for fine mapping of novel genetic elements controlling leaf size in rice.

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