Effects of New Microelement Foliar Fertilizer on Flag Leaf Senescence, Grain Yield and Quality of Spring Wheat

In order to investigate the effects and mechanism of new foliar fertilizer on crop yield and quality, spring wheat (Yangmai 16) was as the experiment material. By applying foliar fertilizer with different dose and times, contents of chlorophyll (Chl), soluble protein (SP), malondialdehyde (MDA) and activities of antioxidant enzymes in flag leaves were studied, and the grain yield and quality were also determined. The results show:contents of Chl and SP, activities of superoxide dismutase (SOD), ascorbate-peroxidase (APX) and glutathione reductase (GR) in flag leaves were all increased under spraying fertilizer, and MDA contents in flag leaves were decreased significantly. Foliar fertilizer spraying increased 1 000-grain weight, grain yield, also increased protein content, wet gluten content, sedimentation and stabilization time of grain. However, these above-mentioned effects were more obvious when fertilizer spray was combined with carbendazim, and these differences all did not reach significant level (P>0.05). There was no significant difference in yield and quality between spraying twice and once (P>0.05). Thus, foliar fertilizer application at flowering or heading stage can prevent leaf senescence and improve chlorophyll content by increasing the leaf antioxidation, and enhance grain filling, grain yield and quality.