Effects of Different Nitrogen Fertilizers on Yield and Photosynthetic Characteristics of Early Rice

The effects of different nitrogen application patterns on photosynthetic characteristics and yield of early rice were studied by the field plot experiment to determine rational application amount of controlled-release nitrogen and promote application of controlled-release nitrogen in rice production.The results showed that nitrogen application could significantly increase leaf chlorophyll content,net photosynthetic rate,stomatal conductance,and transpiration rate,decrease leaf intercellular CO2 concentration and improve photosynthetic performance of early rice compared with CK(without nitrogen application).The leaf chlorophyll content of early rice applied with controlled-release nitrogen with the same nitrogen amount was low at earlier stage but maintain the higher level at later stage compared with the common urea treatment.Leaf chlorophyll content,net photosynthetic rate and rice yield of 90% controlled-release nitrogen treatment was lower than the common urea treatment but the difference between two treatments was no significance.In conclusion,applying controlled-release urea can reduce nitrogen application amount and nitrogen pollution in rice production.