Establishment And Application Of Leaf Age Fertilizer Model Of Corn In Cold Region

In this paper, The basis of the law of nutrient demanding of corn ,nitrogen accumulation and distribution at different growth stages, as well as the distribution of metastasis in different organs, nitrogen recovery rate,using a combination of the traditional leaf age fertilizer and contemporary diagnostic techniques of plant nutrition method. Builded a suitable diagnosis of fertilization model of corn in cold regin, The main results obtained as followed:1. In corn life,the nitrogen uptake of the three major peak were: the jointing stage to tasselling period, tasselling a view to filling period and grain filling stage to maturity. Phosphorus uptake of maize was proceeding with the upward trend in all growth period, and to the ripening period got the greatest.K were mostly accumulated in the stem. The demand of producting per 100 kilograms in maize grain nutrient amount and proportion: 100kg grain per unit volume of the required nutrients: nitrogen (N) 1.94kg; phosphorus (P) 0.38kg; potassium (K) 1.29kg, nitrogen (N), phosphorus (P), potassium (K) absorption ratio was 1:0.22:0.66.2. 2008 Fenghe-1 production descripted: The best treatment was the 150 kg hm-212 leaf-stage treatment.Xinken-3 production descripted: The best treatment was the 150 kg m-210 leaf-stage treatment.With the amount of nitrogen increased,yield first increased then decreased , set up a fertilizer quadratic equation.The best economic and reasonable amount of nitrogen was 148.8 kg hm-2; Experiment in 2009 showed that 40% pop-up + fertilizer topdressing8 leaves 30%+ 12 leaves 30% of top-dressing treatment had the highest yield, relative kinds of fertilizer 40% + 10 leaves 60% of top-dressing treatment had no significant difference. Combination of field production, once adapted to local fertilizer topdressing fertilizer rate is still the main way.The nitrogen recovery rate in different treatments in 2008 were between 13.1%~56.6%. The nitrogen recovery rate in treatment 50 kg hm-212 leaf-stage (Fenghe-1) and treatment100 kg hm-210 leaf-stage (Xinken-3)got the best and it increased with the amount of nitrogen decreased. Top-dressing experiment on nitrogen recovery rate in 2009,showed that 40% pop-up + fertilizer topdressing8 leaves 30%+ 12 leaves 30% of the treatment had high volume.3. The studies of research of the relationship between SPAD values and chlorophyll content and leaf nitrogen content and crop yield in a certain growth period had shown that: different growth stages SPAD values showed a significant quadratic related to the relationship, SPAD values predicted output can be used to achieve nitrogen nutrition diagnosis, rational fertilizer logistics. SPAD peak appeared in the 12-leaf stage (Fenghe-1), 10-leaf stage (Xinken-3),It was indicated that nitrogen from the vegetative organs to gradually shift for reproduct organs,which is a large demand of maize for nitrogen period. Testing determined SPAD threshold was (Fenghe-1) 62 and Xinken-3 was 59.4. Test about the SPAD measurement process showed that the upper leaves was better than the ear leaf. From the leaf base at 40% ~55% coefficient of variation was small. In different growth period 55% of SPAD values and chlorophyll content had the greatest correlation coefficient. Experiment showed that at 1cm from the edge of leaves 55% of the total length value was the best location.