Effect of Nitrogen Fertilizer on Photosynthetic Characteristics of Spring Wheat Leaf

By the pot trial of different nitrogen fertilizer,the photosynthetic characteristics of the last second leaf of spring wheat during flag stage were investigated.Results show that when we appropriately apply nitrogen fertilizer,the maximum photosynthetic rate(P_(max)),the light saturation point(LSP) clearly increase,the light compensation point(LCP),the apparent photon utilization efficiency(α) and the dark respiration rate(R_d) decrease.And so it has been boosted light use efficiency of the leaf of wheat on strong light and slight light.The increase of chlorophyll content and leaf area index may be cause that change of photosynthetic characteristics of leaf of wheat;and the study results indicate that accumulation of dry matter is able to enhance by increasing suitably nitrogen fertilizer.