Root-Shoot Balance in Relation to Grain Formation in Maize Hybrids Differing in Leaf Senescence

摘要

Many characteristics associated with stay-green and their relations to high yield remain unclear. In this study, field experiment was conducted to investigate root-shoot balance in relation to grain formation in maize (Zea mays L.) hybrids with different senescent appearance. The stay-green (Van P3845) and the other earlier senescent (Van Hokkou 55) hybrid were used in this study. In comparison with Hokkou 55, the higher contents of N, ribulose-1,5 -bisphophate carboxyase (Rubisco; EC 4.1.1.38) and phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) and the higher PEPC activity in leaves and the higher specific N absorption rate by roots were observed in P3845, which led to a better balanced C and N metabolism between shoots and roots, resulting in a higher grain yield in stay green hybrid than in earlier senescent hybrid.