| Popis: |
D2 analysis in single cross hybrids of maize over seasons indicated the influence of seasons on clustering patterns based on morpho-physiological and yield components. The cluster analysis assigned the 45 hybrids of maize single cross hybrids into five, six and seven major clusters in rabi, summer, and kharif, respectively based on the quantitative characters indicating the importance of phenotypic descriptors to differentiate between them. The component characters viz., cob girth, kernel weight, and days to 50% tasseling contributed much to the clustering pattern of hybrids in all three seasons, while the number of kernel rows cob-1, number of kernels row-1, cob length, SPAD meter reading, days to 50% silking and specific leaf weight contributed much less to the genetic diversity. Cluster means for different yield contributing characters also varied across seasons maximum being in rabi, kharif, and summer, respectively, while morpho-physiological characters were high in kharif followed by rabi and summer emphasizing the need for multi-environment testing for the identification of stable and superior hybrids. High levels of intra and inter-cluster distances indicated the presence of broad genetic variation between and within a cluster and utilization of them in crop improvement programmes. The top high-yielding hybrids viz., BML 7 × DFTY, BML 15 × PDM 1474, DFTY × Heypool and DFTY × PDM 145 consistently were included in the same clusters over seasons indicating their genetic similarities and stability in performance. |
