Research Of Influence On Relay-cropping Potatoes’ Physiology Effect And Yield Quality By Different Density And Nitrogen Fertilizer

In order to explore the rule of potatoes’ photosynthetic physiology, nutrition physiology and yield formation by different density and nitrogen fertilizer, to get the high yield and good qualitys’configuration on density and nitrogen fertilizer, this experiment studied the potatoes’photosynthetic physiology rule, the accumulation and distribution of NPK, dry matter accumulation and yield formation by different density and nitrogen fertilizer through two facors split plot experiment. Main conclusions are as follows:(1)Influence on concent of LAI, SLW and chlorophyll of potatoes’ photosynthetic leavesThe rule of LAI change was unimodal change in the potato growth period, namely, the maximum value appeared in the starch accumulation stage, and the potato plant in low density (2000 plants/667 m2 and 2600 plants/667m2) has a higher LAI, in 7.5 kg/ 667 m2 nitrogen levels has the highest LAI, and the plant has the lowest LAI without nitrogen. In low density (2000 plants/667 m2 and 2600 plants/667 m2), SLW was reduced and then slightly increased with the advancement, and the minimum value appeared in the starch accumulation stage. The change trend of chlorophyll first increased and then reduced, the maximum value appeared in tuber growth, under the high density, plant has relatively higher chlorophyll concent in middle nitrogen leavel, the chlorophyll content of nitrogen free processing performance was the lowest. If increased density, a moderate amount of nitrogen should be inputted.(2)Influence on photosynthetic physiology of potatoAlong with the change of leaf position, Pn, Tr, Ci, Gs had changed significantly stratified, in totally, Pn, Tr and Gs had a same performance that upper leaves had the highest value, and then was the middle leaves, the lower leaves was the loweswt, but Ci was in contrast. Pn, Tr, Ci, Gs were affected bigger by nitrogen fertilizer than density, plant growed best in density of 3200plants/667 m2, nitrogen fertilizer of 7.5kg/667m2, which had a higher photosynthetic, this was the potato yield of photosynthesis. The research of light and regulation of enzyme(RuBP and SPS) energy results showed the effect of nitrogen fertilizer is greater than the density, the influence of the impact on potato photosynthesis regulation of enzyme activity were the influence law of parabola changes. Among them, the effect of nitrogen fertilizer and density on Rubpcase was the same with Pn, Tr and Gs, that A3B2 was the best, but SPS was in contrast.(3) Influence on nutrition physiology of potatoAs the plant growth period, the accumulations of N, P, K elements in leaf and stem were first increased and then reduced, accumulation in tuber was a trend of increasing, and the accumulation of nutrient elements in different organs arrived the maximum was in different period, the biggest accumulation in leaf was in tuber growth, tuber was in the mature period, stem was not in same period. The influence of nitrogen fertilizer was greater than the influence of density in various nutrient elements accumulation in different organs, the configuration of density of 3200 plant/667m2 and nitrogen of 7.5kg/667m2 was the most conducive to each element in the potato accumulation in different organs. In combination with the result of photosynthetic characteristics, various nutrient elements in different organs was the same with it in different density and nitrogen fertilizer.(4) Influence on dry matter accumulation and potato yield, qualityAs the plant growth period, the accumulations of dry matter in leaf and stem were first increased and then dereased, in tuber was increasing, in totally, A3B2 had the highest dry tuber matter accumulation. RGR results indicated that the most prolific combination in tuber formation to the tuber growth growed fastest, this is the biological basis of yield obtained. The influence of nitrogen fertilizer on interplanting potato yield was bigger than density, nitrogen shortage was serious influencing the formation of production, A3B2 treatment had the highest yield, the commodity potato rate and the number of large and medium-sized potato processing were also higher, namely the best production combination was the configuration by density of 3200 plants/667m2, nitrogen of 7.5 kg/667 m2. Density on the influence of the soluble sugar content was bigger then nitrogen, under the high density, the higher nitrogen fertilization levels, the more the soluble sugar content, nitrogen fertilizer had a bigger effect on starch content, in totally, if want more tuber starch contents, the density can increase appropriately, but should be a medium or medium low nitrogen levels.