Effect of Nitrogen Application on Physiology of Flag Leaf and Grain Yield of Winter Wheat in Central Henan

In order to discuss the efficient nitrogen managements in central Henan province,we selected Bainong'aikang 58 as field experimental material,and studied the effects of nitrogen application on physiology of flag leaves and grain yield of winter wheat with split block design during 2009-2010.The results showed that,effects of nitrogen application on chlorophyll content,net photosynthetic rate,nitrate reductase activity and soluble protein content of flag leaves were significantly(P0.05).These four indexes of flag leaves tended to be higher when total nitrogen fertilizer amount increased,and they were raised significantly by more topdressing nitrogen fertilizer at jointing stage under the same basal nitrogen fertilizer.At the same level of total nitrogen fertilization,there were compensation effects between more topdressing and less basal application.Nitrogen fertilizer managements affected grain yield simultaneously.Among all the treatments,grain number per spike and grain weight tended to be the highest under the treatment of N120+150,while the ear number and grain yield showed the highest under N120+210.From the above,the treatment of N120+150was more rational nitrogen management in central Henan,which was total nitrogen fertilizer application was 270 kg per hectare and basal and topdressing nitrogen fertilizer at jointing stage was 120 and 150 kg per hectare,respectively.