Effect Of N Application And Planting Density On Nitrogen Uptake And Yield Quality Of Mulched Drip Irrigation Potato

The studied materials of the field experiments were potato cv.zihuabai.The research methods are field experiments and laboratory analysis. In this thesis, systematically studied the affect of nitrogen and density on potato Drip Irrigation under film. Research contents are dry matter accumulation, different nitrogen uptake and utilization and the formation of yield and quality.The main results were as follows:1.Potato population dry matter accumulation dynamics and the cumulative nitrogen absorption amount of different nitrogen and density treatments during the whole growth period is a "S" curve. Increasing the amount of nitrogen fertilizer, can improve the population dry matter accumulation and nitrogen uptake; With the increasing of planting density, dry matter accumulation and nitrogen uptake were gradually increased. Nitrogen application combined with density can significantly promote the dry matter accumulation and nitrogen uptake of potato population.2.The chlorophyll content of potato leaves in the whole growth period showed a single peak curve. The period of the tuber formation reached a peak Nitrogen application significantly increased the chlorophyll content of leafs in each period. Increasing planting density improved the content of chlorophyll, but the effect is not significant. Increasing the amount of nitrogen fertilizer, the Pro and MDA of potato leaves are significantly reduced, but the activity of SOD was increased significantly. The affect of planting density on the content of Pro, MDA and activity of SOD is little. In The high-density and low-density combinations, the content of Pro and MDA in potato leaves are higher; the activity of SOD is lower.3.Increasing the amount of nitrogen fertilizer, agronomic efficiency (AE),nitrogen uptake and utilization rate (RE), partial factor productivity (PFP), physiological efficiency (PE) were decreased. With the increasing of planting density, agronomic efficiency (AE), nitrogen uptake and utilization rate (RE), partial factor productivity (PFP) were increased, physiological efficiency (PE) were increased slowly. When planting density was65550～77100plants/hm2and nitrogen fertilizer was142.50kg/hm2,the nitrogen use efficiency are the highest.4.Potato tuber yield increased with nitrogen fertilizer, with the trend of increased at first and then reduced; and with the increase of planting density showed an increasing trend. Increasing the amount of nitrogen fertilizer and planting density, the one thousand kilograms of nitrogen uptake yield and nitrogen consumption coefficient was improved, but nitrogen production efficiency was reduced. When planting density was65550plants/hm2and nitrogen fertilizer was250.00kg/hm2,The potato tuber yield and net profits are the highest, can be used as effective nitrogen density combinations.5.Increasing the amount of nitrogen fertilizer, the tuber and starch yield were increased significantly, starch content decreased significantly, the content of reducing sugar increased significantly. With the increasing of planting density, the tuber and starch yield and starch content were increased; the content of reducing sugar was decreased. Under this experimental condition, When planting density was65550-77100plants/hm2and nitrogen fertilizer was250.00kg/hm2, the potato starch yield are the highest, can be used as effective nitrogen density combinations.6.The tuber and starch yield are very significantly positive correlated with dry weight per plant, content of chlorophyll, nitrogen fertilizer, nitrogen accumulation, nitrogen absorption and nitrogen use efficiency. Nitrogen utilization rate of absorption is significantly positive correlated with cumulative nitrogen absorption amount, but negatively correlated with nitrogen rate.