A set of chromosome segment substitution lines (CSSLs),derived from Asominori/IR24 with Asominori as the recurrent parent,was planted and phenotyped for grain length (GL),grain width (GW) and length-width ratio (LWR) of milled rice in two successive years and four sites.

Using an indica variety 93-11,a japonica variety Nipponbare and seven chromosome segment substitution lines(CSSLs)with a genetic background of 93-11 introgressed from Nipponbare as the materials,we investigated seed shattering with 153 simple sequence repeat(SSR)markers on rice chromosomes,the introgressed segment and the quantitative trait loci(QTL)for seed shattering.

In the paper,with an indica variety 93-11,a japonica variety Nipponbare and 8 chromosome segment substitution lines(CSSLs) with the genetic background of 93-11 introgressed from Nipponbare as the materials,using 153 SSR markers distributed on 12 rice chromosomes,the substituted segment and the QTLs for grain shape were analyzed.

NC II(10×6) experiment derived from crossing between 10 indica-japonica chromosome segment substitution lines(CSSLs) with uniform japonica genome background and 6 japonica testers was conducted to analyze GCA,SCA,and relative genetic parameters of target chromosome segments.

NC Ⅱ(10×6)experiment derived from crossing between 10 indica-japonica chromosome segment substitution lines(CSSLs)with japonica genome background and 6 japonica testers had been conducted to analyze GCA,SCA and relative genetic parameters of target chromosome segments.