Analysis on photosynthesis characteristics in rice under different irrigations
不同水分灌溉下水稻光合特征分析

The cumulation photosynthesis effect in the condition of different irrigations on the paddy has the different results.The contrast of colony photosynthesis efficiency after heading between different irrigations in the paddy is notable but very little in the early paddy.The midday depression always appears regardless of the sunny days or cloudy days in the condition of normal irrigation.The photosynthesis reaches the peak values at 9 o'clock and 15 o'clock in the cloudy days,and at 11 o'clock and 17 o'clock in the sunshine days.Data indicate that the air humidity and the concentration of CO2 are the two dominant environmental factors affecting the photosynthesis peak value.The peak value of Tianguan appears ahead of time by the other measurements in the sunshine days,but: it has the nearly reversed result in the cloudy days.Of the four kinds of irrigation,Tianguan has the weakest photosynthesis velocity,Yanguan has the strongest,and Peiguan stands in the middle.