Relationship between Ear-Removal-Induced Leaf Senescence and Green Score in Maize
1987
Willman, M. R. | Below, F. E. | Hageman, R. H. | Lambert, R. J.
Ear removal (or pollination prevention) in maize (Zea mays L.) accelerates leaf senescence in certain hybrids and may be a useful means of identifying genotypes with extended leaf-area duration independent of grain development. The present study was undertaken to clarify the relationship between ear-removal-induced leaf senescence and leaf stay-green when ears are present, and to determine the effect of hybrid pedigree, relative maturity, and environment on the expression of these two traits. A sample of 130 and 101 commercial and precommercial maize hybrids were evaluated in 1984 and 1985, respectively. The hybrids, representative of seven relative maturity groups, were evaluated as separate groups in separate randomized complete block designs at one of two locations. Four of the seven groups were evaluated in both 1984 and 1985. Plants were visually assessed for the rate of ear-removal-induced leaf senescence and for the percent green leaf tissue on eared plants at physiological maturity. In each maturity group, significant variation among hybrids was observed for both traits. Although seven of the eight yearby-genotype interactions were significant, the proportion of the total sums of squares accounted for by this interaction was minor (6-15%). Simple correlations and comparisons among hybrid pedigrees indicated that the relationship between ear-removal-induced and normal leaf senescence is complex and is influenced by hybrid genotype. The results suggest that ear-removal-induced senescence represents a phenomenon independent of grain development and raise the possibility that this trait may be beneficial as an additional means of identifying hybrids with late-season plant health.
显示更多 [+] 显示较少 [-]