The Effects Of Different Nitrogen Levels On Distribution Pattern Of Photosynthate And Physio-ecological Characteristics Of Winter Wheat

Pot and field experiments were carried out in Feng-qiu Agricultural Experiment station of CAS. Three different treatments were applied, they were: N1 with nitrogen content keeping at 30kg/ hm2; N2 keeping at 120kg/ hm2; N3 keeping at 300kg/hm2. Crop growth, dry matter accumulation and distribution, carbohydrate content in vegetative oragans and physio-ecological characteristics were measured at each development stage. The mechanism of photosynthetic distribution pattern and regulatin of physio-ecological characteristics were revealed. And it is verey significant for the research on the balance between source and pool and divert fertilizer to water to increase production.The results showed that N3 effect growth and development of wheat and dry matter accumulation and transportation in the whole stage.and it is not obvious in the early stage. N3 promotes obviously in the after stage. Compensation period on winter to nitrogen at jointing.The plant hight, tiller numbers, leaf areas, root length, root surface area, root volume were increased after jointing. Totle dry matter and percent of dry matter in stem, sheath, spike increased. The carbohydrate contents were decreased as nitrogen increased, the most in N1 treatment, it can improved osmatically adjustment, then adapted the nitrogen stress condition.The amout of nitrogen can improve the translated amout, but decreased translated ration and contribution ration. The translated amout of stem, sheath were higher, it showed N3 > N2 > N1. The translated ration and contribution ration of stem, corncobs and yingpian were higher, it showed N1 > N2 > N3. From the charecteristic of yield, All Indicators of zhoumai18 were higher than jimai20, and yield was the most in N3 treatment of two types.Form the relationship of dry matter distribution,sucrose content and yield of winter wheat in different growth stages, distribution of dry matter in vegetable oragans was negatively correlated with yield at jointing, correlation coefficients were respectively R=-0.39,R=-0.38,R=-0.47. The positive relation with the growth period forward, it was enhanced in filling, correlation coefficients were respectively R=0.81,R=0.847,R=0.844. Sugar content and yield positively correlated before anthesis, it was higher in jointing, correlation coefficients were respectively R=0.53,R=0.11,R=0.54; negative relation was higher in filling, correlation coefficients were respectively R=-0.31,R=-0.359,R=-0.617.Photosynthetic characteristics, chlorophyll, root activity, soluble protein at nitrogen trentments of wheat were enhanced, it was increased as nitrogen increased. It reaches the maximum in the anthesis stage, and it increased during early stages and then decreased. Relation analysis were found that Pn and carbohydrate content were correlated negatively, correlation coefficient was R=-0.747**, and soluble protein correlated positively, correlation coefficient was R=-0.702**; Tr and water potential correlated positively, correlation coefficient was R=0.784**; Carbohydrate content and soluble protein were correlated negatively, correlation coefficient was R=0.783**.