Effects Of Phosphate Fertilizers On The Growth And Rhizosphere Process Of Spring Maize Under Different Sowing Dates

In early spring,temperature is critical for soil phosphorus efficiency in Northeast China.Ordinarily,regulation of phosphorus fertilizer is one of solutions to improve the rhizosphere process so as to improve the phosphorus efficiency and yield of spring maize at low temperature.However,such research on black soil region in Northeast China is very limited.In this paper,field experiments were carried out to study the effects of sowing date(early sowing and conventional sowing date)and phosphorus fertilizer regulation mode(ratio,dosage,location,stages)on the capacity of soil phosphorus and shoot growth of spring maize,in order to find out effective ways to reduce phosphorus fertilizer and increase nutrient efficiency in black soil region of Northeast China.The main results are shown as follows:1.Under the condition of early sowing,the yield of treatments with phosphate fertilizer was higher than that of no phosphate fertilizer.Whereas,the increasing was not obvious under conventional sowing.2.Compared with farmers' habitual fertilization,application of monoammonium phosphate or polyammonium phosphate as the starter fertilizer maintained the yield despite reducing 25% of phosphorus fertilizer,no matter sowing dates.3.Under the condition of early sowing,phosphorus uptake of the plants at seedling stage significantly showed positive correlationship with the yield(r=0.750**,n=12).It indicates that the available phosphorus content and phosphorus uptake of the plants at seedling stage could be improved by optimizing the phosphorus fertilizer regulation,so as to realize the goal of production increase.