Effects Of Reduction Of Chemical Fertilizer Combined With Application Of Bio-organic Fertilizer On Peanut Growth And Soil Microbial Community

In view of the problems of soil ecological environment deterioration,fertilizer utilization rate reduction and peanut quality reduction caused by excessive dependence on chemical fertilizer in peanut production in China,In this paper,Xianghua 9760 was selected as the research object,and seven different treatments were set up: CK(no fertilizer),H(100%fertilizer),I(80% fertilizer + 20% bio-organic fertilizer),J(60% fertilizer + 40% bio-organic fertilizer),K(40% fertilizer + 60% bio-organic fertilizer),l(20% fertilizer + 80%bio-organic fertilizer),M(100% bio-organic fertilizer).The effects of different fertilization treatments on peanut,dry-matter accumulation and distribution,yield components,soil fertility and microbial community structure were studied.The main results were as follows:1.Based on field micro-plot experiment,effects of different fertilizer treatments on the chlorophyll content,main agronomic characters,protective enzyme activity,MDA content,yield components,soil fertility and microbial community structure of peanut leaves were discussed.The results showed that the SPAD value of chlorophyll,the height of main stem and the length of the first lateral branch of peanut were 5.63%-22.07%,6.11%-25.72%;7.22%-28.60%,4.81%-25.12%;1.03%-67.13%,2.82%-71.29% higher than those of the pure fertilizer group and the control group respectively;The dry matter accumulation of the upper plant,R/V(reproductive organ/vegetative organ)and the harvest index were all higher than those of the control group and the pure fertilizer treatment group SOD,PODand CAT activities were significantly higher than those of the control group and the purified fertilizer group,and MDA content was significantly decreased;The number of full fruit,100 fruit weight,full fruit rate,pod yield per plant and 100 fruit weight were all higher than those of the control group and the pure fertilizer treatment group.Compared with the control group and the pure fertilizer treatment group,the yield per mu increased by 16.65% and 11.27%respectively,and the content of organic matter,total nitrogen,total phosphorus,total potassium and available nutrients in the soil increased significantly,but the pH value of the soil was decreased.2.The high-throughput sequencing technology of Illumina miseq platform was used to study the effect of different fertilizer treatments on the bacterial diversity of root soil.The results showed that the richness and diversity index of the bacterial community in the root soil of the treatment group with reduced fertilizer and bio-organic fertilizer were higher than that of the control group and the pure fertilizer treatment group.With the promotion of peanut growth period,Chao1,Ace index and shannon index showed a trend of increasing first and decreasing.Acidobacteria;Proteobacteria;Actinobacteria;Chloroflexi;Gemma timonadetes;Verrucomicrobia;Bacteroidetes;Rokubacteria;Planctomycetes;Nitrospirae;Sphing omonas;Gemmatimonas and Bryobacter were distributed in the root soil of each growth period,but different fertilization treatment just changed its distribution proportion.