Effects Of Short-term Pig Manure Composting On The Allelopathy Of Typical Phenolic Acids In Strawberry Cultivation Soil

Continuous cropping is the most common production mode in modern intensive,largescale agricultural and horticultural production.Long-term continuous cropping will bring about a series of soil problems such as soil degradation,secondary salinization,accumulation of autotoxic substances,and aggravation of soil-borne diseases,resulting in abnormal growth and development,deterioration of crop yield and quality of the same crops or closely related crops,which is the continuous cropping obstacle.Continuous cropping obstacle is particularly prominent in facility agriculture,which in China severely affects and limits the sustainable development of modern agriculture,and becomes an urgent problem that needs to be solved in facility cultivation.The continuous cropping obstacle of crops is closely related to the allelopathy of allelochemicals in root exudates,and phenolic acids are important allelochemicals in a single continuous cropping system,so it is of great significance to alleviate the continuous cropping obstacle by regulating the content of phenolic acids.Organic fertilizers are economical and easy to obtain,are rich in organic matter and plant nutrients,and have great advantages in alleviating continuous cropping obstacles.At present,however,most of the organic fertilizer’s concerns in removing obstacles to continuous cultivation in the soil are aimed at improving the fundamental chemical properties and microbial community of the soil,while few studies have investigated the effects of organic fertilizers on the dynamic content of phenolic acids in soil and their allelopathic effects.Therefore,it is an important way to play the role of organic fertilizer in regulating phenolic acid content and relieving continuous cropping obstacles to strengthen the research on the action mechanism of organic fertilizer on soil phenolic acid and its interaction mechanism with soil,plants and microorganisms.In this study,five typical phenolic acids in strawberry continuous cropping soil,p-hydroxybenzoic acid(pHBA)、vanillic acid(VA)、p-coumarin(PA)、ferulic acid(FA)、cinnamic acid(CA),were selected,and red loam soil and strawberry continuous cropping soil for 1 year were used as experimental objects,soil basic physical and chemical properties,content of nutrient elements,Content and dynamic changes of phenolic acids,enzyme activity,colony characteristics were determined to explore the effect of short-term pig manure compost on the allelopathy of typical phenolic acids in strawberry cultivation soil.The main findings are as follows:(1)The contents of five phenolic acids added by exogenous decreased significantly within 5 days,and then the degradation rate slowed down.The degradation rate was 9.50%-45.39%in 30 days;The degree of acidification showed a promoting effect on PPO activity and allelopathic inhibitory effect on soil alkaline protease,alkaline phosphatase,urease and sucrase activities,and the inhibitory effects of different phenolic acids were different.Phenolic acids reduced the germination rate and delayed the germination time of strawberry seeds,among which FA had the strongest inhibitory effect;(2)Pig manure composting increased the total soil carbon,nitrogen,phosphorus and potassium content;the soil pH increased by 0.9 on average,which reduced soil acidification and promoted five phenolic acids to varying degrees and improved soil enzyme activities,accelerates the germination of strawberry seeds and improves the final germination rate of seeds,and effectively relieves the allelopathic inhibitory effect of exogenous addition of phenolic acids;(3)Five typical phenolic acids were detected in the strawberry cultivation soil with continuous cropping for one year,among which pHBA content was the highest,followed by VA;The effect is the most significant,the degradation effect of PA is the best,and there is no significant effect on the content of CA;(4)Short-term application of pig manure improved soil physical and chemical properties and nutrient conditions;enhanced soil-related enzyme activities,promoted the germination of strawberry seeds;increased OUT abundance and Alpha diversity of soil bacterial and fungal communities;improved the degradation of phenol,polycyclic aromatic hydrocarbons and other aromatic compounds related to the bacterial Sphingonas,and strawberry root rot-related harmful fungi genus The abundance of Fusarium,Penicillium and Aspergillus,which may play an important role in protecting strawberry roots from pathogenic bacteria,decreased the abundance of Ralstonia,Saccharimonadaceae,Brevundimonas,Fusicolla and other genera,resulting in the relative abundance of soil bacterial and fungal community species difference,however,Verticillium dahliae,which causes Verticillium dahliae,and Rhizoctonia,which causes black root rot,were not detected.To sum up,short-term pig manure composting can alleviate the allelopathic inhibition of exogenous phenolic acids,improve soil quality,increase the activities of soil-related enzymes,reduce the content of phenolic acids in soil,promote seed germination,and have an improvement effect on strawberry replanting soil.