Effects Of Deep Tillage During Fallow Period And Phosphorus Fertilizer On Soil Water Stoage,Yield,Grain Quality And Utilization Efficiency Of Water And Fertilizer Of Dryland Wheat

In order to explore the optimum amount of phosphorus application under the condition of deep tillage of dryland wheat,the experiment was carried out in dryland wheat experiment base of Shanxi Agricultural University in 2016-2017,Yunhan 618 as test material,under the deep tillage and traditional tillage(CK),six phosphorus application P2O5 0 kg·hm-2、75 kg·hm-2、150 kg·hm-2、225 kg·hm-2、300 kg·hm-2、375 kg·hm-2 to study the effects of different phosphorus application on soil moisture,soil physical and chemical properties,root growth characteristics,population structure,plant nutrient utilization,yield and quality of dryland wheat.Main result were as follows:(1)After deep tillage during fallow period,the water storage efficiency was increased by 48%,increased the moisture at sowing stage by 32 mm,pre-wintering stage by 18-26 mm,jointing stage by 20-27 mm,booting stage by 25-32 mm,anthesis stage by 2-8 mm,maturity stage by 6-17 mm,and the soil water storage from wintering stage to booting stage was significantly highest under P2O5150 kg ·hm-2.(2)Compared with CK,the content of available P and organic matter in 0-40 cm layer from sowing stage to maturity stage were increased,and the organic carbon and particulate organic carbon in surface layer at maturity stage were increased,The activities of urease,alkaline phosphatase,invertase and catalase increased in 0-40 cm layer from pre-winter stage to maturity stage.Soil nutrients and soil enzyme activities at different stage,organic carbon content at maturity stage were the highest under P2O5 150 kg·hm-2.(3)The total root length,the total root system area,the total projection area and total root volume of 0-80 cm under deep tillage were higher CK.The root growth characteristics of all soil layers also increased at the jointing stage.The total root length,total root surface area,total projected area and total root volume of 0-80 cm in each growth period were the highest under P2O5150 kg ·hm-2.(4)The number of group tillers and plant dry matter,the dry matter mass of the middle and late growth stage,the dry matter accumulation after anthesis and the contribution rate to the grain after deep tillage were higher than CK.The group tillers,dry matter accumulation during jointing to anthsis stage and during anthsis to maturity stage and the ratio,the amount of dry matter accumulation after anthsis stage and the contribution to the grain were the highest under P2O5150 kg·hm-2.(5)Compared with CK,the amount of plant phosphorus accumulation at different stage and the accumulation of phosphorus in various organs at maturity stage were increased under deep tillage,which was increased by 3%-21%of phosphorus recovery,8%-30%of phosphorus agronomic efficiency,13%-16%of phosphorus partial factor productivity.The phosphorus accumulation amount,he accumulation of phosphorus in various organs at maturity stage,phosphorus recovery,phosphorus agronomic efficiency and phosphorus contribution rate were the highest under P2O5150 kg·hm-2.(6)Compared with CK,the plant nitrogen accumulation at different growth stages,the amount of nitrogen translocation pre-anthesis,the nitrogen accumulation amount after anthesis and the contribution to the grain were increased significantly under deep tillage,which was increased by 14%-21%of nitrogen absorption efficiency,13%-16%of nitrogen productive efficiency,however,nitrogen translation amount before anthesis and the contribution to the grain were decreased.The plant nitrogen accumulation during the wintering to maturity stage,the amount of nitrogen translocation before anthesis,the nitrogen accumulation amount after anthesis and the contribution to the grain,the nitrogen absorption efficiency,the nitrogen production efficiency were the highest under P2O5 150 kg ·hm-2,but nitrogen use efficiency was decreased.(7)Compared with CK,deep tillage during fallow period increased the plant height,ear length and number of bearing spikelets at maturity stage,1000-grain weight per plant 5-35 days after anthesis and the grain filling rate,which was increased by 6%-9%of the spike number,13%-16%of yield,4%-11%of water use efficiency,the number of sterility spikelets was decreased.The plant height,spike length,number of bearing spikelets,filling rate,yield and water use efficiency of P2O 150 kg·hm-2 were the highest.(8)Compared with CK,the protein content and its component,the protein yield were increased under deep tillage during fallow period,which was increased by 2%-4%of the content of soluble sugar,4%-20%of sucrose content.Grain protein content and its components,protein yield,soluble sugar content and sucrose content were the highest under P2O5150 kg ·hm-2.(9)In addition,under six phosphorus application P2O5 deep tillage during fallow period,the soil moisture before anthesis were closer relation with the dry matter accumulation afterantheis than before anthesis,the soil enzyme activity was higher and the fertility was better,which was benefit to increase yield.In all,deep tillage during fallow period is benefical to store precipitation,improve soil moisture,use soil moisture at each growth period effectively,improve soil nutrient and enzyme activity,promote root growth and absorption of nitrogen and phosphorus in soil,form more tillers and build a reasonable population,promote the accumulation of plant dry matter,dry matter accumulated after anthesis to the grain,which is conducive to the accumulation of plant nitrogen and phosphorus,more nitrogen and phosphorus to the grain,to improve the utilization of nitrogen and phosphorus,optimize the yield structure,increase yield and efficiency,increase the grain quality at maturity,and phosphorus application 150 kg·hm·2 was better.