Comprehensive evaluation of dehydration of maize hybrid combinations based on principal component analysis
[Objective]To study the yield traits of 36 maize hybrid combinations and do a comprehensive evaluation of the rate of grain dehydration at harvest in the hope of selecting the varieties with fast grain dehy-dration,for the breeding of sports materials of high generation group.[Methods]Using 4 maize inbred lines as test species and 9 maize high generation lines as pending test lines,NCII incomplete double-diallel hybrid group was adopted to comprehensively evaluate the correlation,principal component,membership function and cluster analysis of grain dehydration rate and yield characters.[Results]The results showed that the order of variation coefficients of various characters in the hybrid combination was as follows:growth period<plant height<ear diameter<number of rows per ear<shaft diameter<hundred-grain weight<number of grains per row<ear length<ear height<corncob water content<single grain weight<grain dehydration rate<grain water content at harvest<bract water content<grain dehydration water content<bald tip length;and the bald tip length was 64.63%and grain dehydration water content was 27.31%,the growth pe-riod was only 1.39%.The grain water content at harvest was positively correlated with plant height,ear diame-ter,grain number per row and growth period.The grain dehydration rate after maturity is significantly negative-ly correlated with plant height,ear diameter,grain number per row and growth period was extremely signifi-cantly negatively correlated with the corncob water content at maturity.The characteristic vector-value and contribution rate of the first eight principal components reached 86.39%.[Conclusion]According to the con-tribution rate of each comprehensive index,based on the comprehensive index of cluster analysis,7 hybrid combinations with fast dehydration have been selected,which is conducive to mechanical harvest.These excel-lent combinations have utilization value in breeding.