豫西黄土高原果园生草对土壤线虫群落及结构的影响

Effects of Orchard Grass Cover on Soil Nematode Community and Structure in the Loess Plateau of Western Henan Province

土壤线虫是土壤生物中最丰富的后生动物,从线虫群落结构角度评价果园不同覆盖作物的土壤质量可为果园管理提供依据。2022年在黄土高原东部果园开展实验,供试品种为‘富士’苹果(Malus domestica cv. Fuji),处理包括:农田、单播毛苕子(Vicia sativa L.)、单播黑麦草(Lolium perenne L.)。与农田对照相比,覆盖毛苕子线虫总丰度及食细菌线虫相对丰度分别显著提高了302.33%和38.41%,植物寄生线虫与杂食和捕食线虫的相对丰度分别降低了62.18%和86.12%。覆盖黑麦草较对照处理导致杂食和捕食线虫的相对丰度降低了55.59%。土壤微生物碳含量、变形菌门相对丰度、土壤pH值、豆科生物量比例是影响线虫群落结构的主要因子。果园行间覆盖毛苕子可优化线虫群落结构,有利于果树根系的生长,建议豫西黄土高原果园生草选择豆科物种毛苕子为益。

Soil nematodes are the most abundant metazoans in soil ecosystems.Evaluating the soil quality of cover crops in orchards from the perspective of soil nematode community structure can provide a theoretical basis for ecological orchard management.This experiment was conducted in an apple(Malus domestica Fuji cultivar)orchard located in the eastern Loess Plateau in 2022,which was planted in 2019.Taking the cropland as the control,the crop cover treatments included Vicia sativa and Lolium perenne monoculture,respectively.In comparison to the control treatment,the Vicia sativa cover crop treatment significantly increased the total abundance of soil nematodes and the relative abundances of bacterial-feeders by 302.33%and 38.41%,decreased the relative abundances of plant-feeders and omnivorous-predators nematodes by 62.18%and 86.12%.The Lolium perenne treatment significantly decreased the relative abundance of omnivorous-predators by 55.59%.Soil microbial biomass carbon content,the relative abundance of Proteobacteria,soil pH,and leguminous proportions were the main factors influencing the soil nematode community structure.In conclusion,the Vicia sativa cover crop significantly changed soil nematodes community structure and protected the growth of fruit tree roots.Therefore,Vicia sativa,a leguminous species,as a cover crop in ecological orchard management practices in the Loess Plateau of western Henan Province.