Correlations among grain quality traits of different hybrid rice in different years

An analysis to determine the correlations of the grain quality traits of different hybrid rice in different years was conducted in various regions in Fujian from 2003 to 2005.Twelve indices were employed for the quality evaluation on 282 hybrid rice varieties,including early indica,medium season indica and late indica.Significant positive or negative correlations were detected between(a) brown rice rate and milled rice rate,(b) chalky rice rate and chalkiness degree,(c) gel consistency and quality indices,(d) chalky rice rate and transparency,(e) chalky rice rate and quality indices,and(f) amylose content and quality indices in the 3 rice types;and,also between(a) chalky rice rate and amylose content in early and medium season hybrid rice,(b) gel consistency and amylose content in early and late hybrid rice,and(c) head milled rice rate and grain length of medium and late hybrid rice.It was also found that the correlations among 9 traits were significant and stable regardless of year,rice types or varieties.The information might be of value in the breeding of hybrid rice.