Study On Efficiency Applying Fertilizer On Corn In The New Cultivated Gray-Calcium Soil

In Ningxia, newly explored gray-calcium soil is an important agrarian resource to be developed. Focusing on the deficiency of mineral nutrients and lower productivity in gray-calcium soil, a four-year long turn experiment was carried out to investigate the effects of P fertilizer application on the improvement of soil fertility and on the yield of corn. The main results were shown as follows:1 Applying of P-fertilizer increased the yield of corn significantly in newly cultivated gray-calcium soil in experiment season, the residue effects of P fertilizer on the following crops were sustained to three years. The residue effects were increased with increasing of P application. was able to The soil available P was increased by rapidly by applying of P-fertilizer. When doses of P₂O₅ applied were 138.0 kg,207.0 kg,279.0 kg and 414 kg per hm² , the available-P was increased by 1.8mg/kg¹0.4 mg/kg comparing with the non-fertilized treatment.2 Using N-fertilizer or organic fertilizer only could make a remarkable yield increasing as well as using NP, NPZn or NP-fertilizer only. There into, treatment only used N-fertilizer by 255 kg/hm2 could averagely make a higher yield the unfertilized treatment (comparison) by 46.9%;And treatment fertilized more P₂O₅ by 103.5²07.0 kg/hm²could averagely increase yield more than the unfertilized treatment (comparison) by 31.3% as well as rapidly effective-phosphorus by one or two times; Yield of treatment which is added more ZnSO₄ . 7H₂O 45 kg of /hm² in the first year increased by 7.7% averagely than NP-proportion one. Effectual zinc in soil also has been enhanced by 1¹.5times; Yield of the treatment which is added more manure of sheep 11250²2500 kg of per hm2 has been increased by 14.1% averagely than NP-proportion one. The content of organic materials in soil synchronously makes a 30% approximate increasing. The author consequently make a suggestion that in early days of corn growing fertilization should be emphasized on stabilizing N-fertilizer, increasing P-fertilizer and supplementing Zn-fertilizer. With the development of corn production the emphases should transform to stabilizing N-fertilizer, controlling P-fertilizer and adding organic fertilizer.