Association Analysis over Seasons among Morphological, Physiological and Yield Components with Kernel Yield in Maize (Zea mays L.)

Abstract

Forty five single cross hybrids made from 10 inbred lines of maize through diallel mating design were evaluated for three seasons viz. rabi, summer and kharif from 2016-17 to 2017-18.Kernel yield had consistent significant and positive associations with SPAD meter readings, specific leaf area, cob length, cob girth, number of kernel rows cob-1,number of kernels row-1,100 kernel weight and harvest index in rabi, summer and kharif seasons. Similar trend of positive and significant association of kernel yield with all the above characters were recorded at genotypic level indicating existence a close relationship among these characters. Days to 50% tasseling, days to 50% silking, days to maturity and specific leaf weight showed consistent negative and significant correlations with kernel yield both at phenotypic and genotypic level indicating yield penalty with increase in days to 50% tasselling, days to 50% silking and specific leaf weight because more of vegetative growth and less time for reproductive growth which consequently  lead to less kernel yield. The associations of anthesis-silking interval with kernel yield were consistently negative and non-significant in all the three seasons at phenotypic level revealing that narrow interval of anthesis silking interval facilates good seed setting. Plant height showed either negative and significant or negative but non-significant association with kernel yield across seasons suggesting that any increase in plant height  may lead to reduction in kernel yield  and thus  medium plant  height is desirable for recording higher kernel yields in Maize.  Based on the results of character association analysis it was concluded that SPAD chlorophyll meter readings, specific leaf area, cob length, cob girth, number of kernel rows cob-1, number of kernels row-1, 100 kernel weight and harvest index might be given due importance, while formulating selection indices aimed at kernel yield improvement as these characters had showed consistently positive and significant associations with kernel yield. A plant  with medium plant height and duration coupled with higher SPAD meter readings, specific leaf area, cob length, cob girth, number of kernel rows cob-1,number of kernels row-1,100 kernel weight and harvest index is desirable for getting higher kernel yield in maize.