Ideal Type of Rice Core Germplasm Huanghuazhan and Its Derivatives with Good Grain Quality

To construct the ideal type of core germplasm Huanghuazhan and its derivatives,the performances of Huanghuazhan and its pedigree varieties were investigated in early and late-cropping seasons of 2007 in Guangzhou,China (113°17'E,23°8'N). In early-cropping season,the yield was significantly and positively correlated to spikelet number per panicle (r=0.716) and the length of the 2nd top leaf (r=0.825),and significantly negatively correlated to productive panicle number per plant (r=-0.795). Every 1 unit increase in the spikelet number factor caused an increase of 3.17 unit in yield. In late-cropping season,the yield was significantly and positively correlated to 1000-grain weight (r=0.734). Eating quality was significantly and positively correlated to length of flag leaf,length of the 2nd top leaf and length of the 3rd top leaf,with correlation coefficients of 0.798,0.794 and 0.831,respectively. Every 1 unit decrease in the flag leaf width factor had a 2.06 unit increase in yield. Ideal type of the core germplasm Huanghuazhan and its derivatives for early cropping season was different from that for late-cropping season. Emphasis should be paid on selection of the plant type with fewer panicles,bigger and longer panicle,and longer functional leaves in early-cropping season and higher 1000-grain weight,longer and narrower functional leaves in late-cropping season in the breeding nursery in Guangzhou,China.