Study On N And K Managment And Nutrition Diagnosis Techniques Of Corn In Cold Region

In recent years, nitrogen fertilizer supper- potassium scarcity resulted in of yield-increasing effect droop and environmental pollution problem in our country corn capacity,especially north coldly corn capacity. This text systemly analysed on spring corn nutrient accumulation, transfer law, yield, quality and recognize that potassium and nitrogen's best dosage. The results are as follows:1. Nitrogen accumulation of the corn stem leaf performanced for raise first behind lower of trend, hited maximum at tasseling stage, N accumulation had positive correlation with yidld at 0.01 significant level after tasseling stage, and the bigger N accumulation, and the higher herbage yield of maize. N accumulation performanced for the up-trend in seed at whole time, and N accumulation of A2B2(N 150 kg·hm^-2+K₂O100 kg·hm^-2) treatment was maximum. The proper N/K could promote N in the nourishment body to transport to the seed shot, but nitrogen potassium shortage and the nourishment body N transshipment abundance could spark nourishment body progeria. Excess of nitrogen potassium dosage, nourishment body nitrogen metabolized prosperous, nitrogen of seed reduced, the yield was lower.2. Stem leaf's potassium accumulation raised first, and then lowed, and hited maximum at tasseling stage. Seed shot's potassium accumulation was slow-moving to raise, and the opposite contents was lower, which explained , at yield forming process, that the potassium only took part in seed metabolism process, and the big fraction moved from seed behind potassium's physiology function completes, and hardly stored in the seed.3. The N, K cooperativeness and amount of foot were advantageous to growth of the plant nourishment body and the life of the extension function leaf, and were advantageous to compose photosynthesis. The testing showed: the A2B2(N 150 kg·hm^-2+K₂O100 kg·hm^-2) treatment had highest yield, N/K was 2.09, and indicated higher-or lower N/K were disadvantageous to form yield. The yield increased as the amount taxed increases at the same N/K level, the reasonable N/K wanted to hit the best yield level, had to exchange the effect of N/K cooperativeness by fertilizer quantitative increase.4. The plant dry matter weight was up-trend, and the caulis leaf dry matter descended after raised first at the whole time, and took out tasseling-filling stage to hit maximum. The dry matter weight change of different nitrogen potassium dosage had a dissimilarity, the A2B2 (N 150 kg·hm^-2+K₂O100 kg·hm^-2)treatment expressed a good trend. Dry matter weight did not proper higher or lower, and the lower leaded dry matter backlog and transfered toward seed at later stage, and the higher lead decline of yield.5. Effect of N and K dosage on yield: The best economic reasonable dosage of nitrogen was 170.7 kg/hm2, the best economic reasonable of potassium was 106.9 kg/hm². N and K dosage hasd little influence on yield, and content of protein and starch are all highest in A2B2 (N 150 kg·hm^-2+K₂O100 kg·hm^-2)treatment.6. The obvious correlativity existed between leaf SPAD readings and yield at different growth and development period. The relativity of 12th leaf was maximum for 0.8253 in upper position leaf, and that of the tasseling stage was maximum for 0.8151 at ear position.