Effects of nitrogen on photosynthetic characteristics of leaves from two different stay-green corn (Zea mays L.) varieties at the grain-filling stage

Li, G., Zhang, Z.-S., Gao, H.-Y., Liu, P., Dong, S.-T., Zhang, J.-W. and Zhao, B. 2012. Effects of nitrogen on photosynthetic characteristics of leaves from two different stay-green corn ( Zea mays L.) varieties at the grain-filling stage. Can. J. Plant Sci. 92: 671–680. The effects of nitrogen on the photosynthetic characteristics of two different stay-green corn (Zea mays L.) at the grain-filling stage were studied. Using a stay-green inbred line (Q319) and a non-stay-green inbred line (HZ4) as materials, using fast chlorophyll fluorescence-induction kinetics and 820 nm light-absorption curves, we analyzed the influences of nitrogen supplementation on photosystem I (PS I) and photosystem II (PS II). The results show that nitrogen fertilization has significant effects on promoting the net photosynthetic rate (P n ) in leaves at the grain-filling stage and on single-plant grain yield at the harvest stage (P n and grain yield were still significantly lower than those of Q319.