Relationships between panicle and the grain quality traits of hybrid sorghum

This study aimed to understand the relationships between panicle traits and the grain quality traits of hybrid sorghum. Using 58 hybrid combinations of sorghum, panicle traits (spike length, spike-stalk length, primary branch number, secondary branch number, grain number per spike, thousand seed weight, and single grain yield) and grain quality traits (crude protein, crude fat, starch, amylopectin, and tannins) were analysed by correlation and grey correlation analysis. Correlation and grey correlation analysis were based on the relationship between the main panicle traits and single grain yield showed similar results, and the sequence of the relationship was thousand seed weight>grain number per spike>secondary branch number>primary branch number>spike length>spike-stalk length. However, relationships between panicle traits and quality traits differed between the two methods of analysis. Grey correlation analysis showed a weak correlation between panicle character and tannin content, and that spike length, spike-stalk length or spike grain number and the three characters of grain quality traits had stronger correlation. Correlation analysis showed that crude fat content had strong significant negative correlation with spike length and spike-stalk length; Starch content had negative correlation with grain number per spike and was significantly positively related to thousand seed weight; Amylopectin had a significant negative correlation with grain number per spike and spike length; Tannins had strong significant negative correlation with primary branch number and secondary branch number, and was significantly negatively related to thousand seed weight. Correlation analysis results were more accurate than those of grey correlation degree analysis. As such, correlation analysis results can provide a theory basis for high yield and high quality sorghum hybrid breeding.