Effects of Different Doses of Control Fertilizer for Continuous Cropping Obstacle on Soil Physical Properties and Economic Benefits of Corn Seed

Objective To study the effects of different doses of control fertilizer for continuous cropping obstacles on soil physical properties and the economic benefits of corn.MethodField test method was used in 13 years continuous cropping soil of maize seed.Using field experiment method,in order to control corn continuous cropping obstacle of Fertilizer Design 7 treatments for the gradient were: CK,0.85,1.70,2.55,3.40,4.25 and 5.10 t/hm2.no fertilizer as CK,each treatment was repeated 3 times,randomized block design.ResultAlong with the increase of continuous cropping obstacle control fertilizer from 0.85 t/hm2 to 5.10 t/hm2,compared with the control,the soil total porosity,aggregates,saturated water content were increased by 6.42;,14.63;and 17.91;,and soil bulk density decreased by 11.11;,which was a significant difference(P< 0.01);Maize plant height,stem diameter,growth rate,fresh weight and dry weight on the ground were increased by 26.06;,32.12;,26.05;,48.05;and 48.06;,respectively with significant differences(P < 0.01);Corn kernel number,kernel weight and 100 kernel weight were increased by 52.24;,46.06;and 20.70;with significant differences(P< 0.01);The corn yield was increased by 46.04;with significant difference(P < 0.01);but the increased yield of fertilizer per kilogram for continuous cropping obstacle decreased by 63.64;with the increased amount of the fertilizer.ConclusionWhen the control fertilizer application amount of continuous cropping obstacle was more than 3.40 t/hm2,the negative value in profit of fertilization appeared,from which it is clear that the amount should be better below 3.40 t/hm2.Applying this amount,the theoretical corn yield is probably over 6.91 t/hm2,reaching the best economic benefit.