果园绿肥对果树-土壤-微生物系统影响研究进展

Research progress on the influence of orchard green manure on fruit treesoil-microbe system

绿肥覆盖是有效改善生态环境,提高果园土壤质量,减少水土流失,增加土壤养分含量,改善土壤微生物群落的重要管理措施。我国果树生产长期大量使用化肥,造成土壤质量下降,果树生长受阻,果品质量降低。为缓解上述问题,国家开始全面推行果园、茶园绿肥有机肥代替化肥。综述了国内外1981—2020年果园绿肥对果树生长及果品、果树病害、果园土壤理化性质和养分含量及土壤微生物影响的研究进展。间作绿肥影响土壤性质、果树光合作用及根系生长分布,提高果树抗逆酶活性,促进果树生长。果园间作绿肥改善了土壤团粒结构、土壤机械稳定性、土壤孔隙率和抗侵蚀性,降低了土壤容重,影响果园土壤的含水量、pH值和养分含量,改善了果树的生长条件。间作绿肥增加了果园土壤中促生长菌或共生微生物以及与养分分解和循环有关的微生物数量及多样性,有利于提高植物吸收养分的能力,促进植物生长,提高果树抗逆性,加速分解绿肥残体,促进了果园养分循环,提高果园的生产力。土壤中病原体的含量与植物的健康密切相关。绿肥间作减少了土壤中病原体,减少了果树病害的发生。改善果园小气候,有利于果树生长。并对该领域相关研究进行了展望,以期为果园绿肥的应用提供参考。

Fruit tree planting area and total output in our country are at top rank in the world.By 2019,orchard area in China had reached 122.7668 million hm2.In order to maintain high yield of fruit trees,large quantities of chemical fertilizers are applied.Long-term use of chemical fertilizers causes soil compaction,soil quality loss,tree growth suppression,fruit quality reduction,and serious pests and diseases.Green manure coverage is an important measure to improve soil quality,reduce soil erosion,increase soil nutrient content,and improve soil microbial community in orchard.China has begun to implement organic fertilizers in orchards and tea gardens to partly replace chemical fertilizers.Intercropping with green manure affects the soil properties,photosynthesis of fruit trees,and root growth and distribution,and increases the activities of stress resistance related enzymes in fruit trees,which results in promotion of fruit tree growth with increased tree height,crown size,water use efficiency and leaf nutrient content.However,green manure has both positive and negative effects on the yield and quality of fruit trees.In actual production,the characteristics of fruit tree at different stages,green manure,and regional climate should be taken into consideration for application of green manure.In order to prevent green manure plants from competing with fruit trees for water and nutrients in the soil,the overlap of the growth period of green manure with the period of flowering and fruit setting of fruit trees and other periods of high nutrient and water demand should be avoided.Intercropping with green manure changes the content of antagonistic bacteria against pathogens in the soil,increases the diversity and abundance of other beneficial microorganisms in the soil,and competes with pathogens for resources such as space and nutrients.The compounds produced by the decomposition of green manure inhibit the growth of pathogens in the soil,and thereby promote the growth of fruit trees,improve the overall health and resistance of fruit trees,and reduce the occurrence of fruit tree diseases.However,the use of green manure is mostly for covering and overwintering.Plant residues provide nutrients and a living environment for pathogens to survive and overwinter,and thus increase the accumulation of pathogens in the orchard and the risk of diseases.Green manure improves soil aggregate structure,mechanical stability,porosity and erosion resistance,reduces soil bulk density,and changes soil water content,pH,and nutrient content.The growth conditions of fruit trees are improved through these effects.The current research on the influence of green manure on the composition of the microbial community in orchard soil mainly focuses on the effect on growth-promoting bacteria or symbiotic bacteria,bacteria related to nutrient decomposition and cycling,and soil-borne pathogens.Intercropping with green manure increases the abundance of growth-promoting bacteria or symbiotic microbe,and bacteria related to nutrient decomposition and cycling in orchard soil,which is beneficial to increase the ability of plants to absorb nutrients,promote plant growth,improve plant resistance,and accelerate the decomposition of green manure crop residue.Soil microbe promotes nutrient circulation in the orchard and improves the productivity of the orchard.The content of pathogen in the soil is closely related to the health of plants.Intercropping with green manure in orchards usually reduces the infection of plant by soil-born pathogens.So far,scholars at home and abroad have carried out series of studies of the effect of green manure on fruit tree growth and fruit products,fruit tree diseases,soil nutrients and physical and chemical properties.Some new technologies,such as high-throughput technologies,have been used in the study of soil microbial community structure,soil beneficial microorganisms and soil pathogen.Intercropping with green manure reduces diurnal temperature differences,increases air humidity,improves the growth environment of fruit trees,which helps to form a microclimate with the characteristics of the fruit tree-green manure intercropping system and directly affects the growth and yield of fruit trees.These studies have effectively promoted scientific research and application of green manure in orchards.At present,application of green manure in orchards in China is still at a small scale.There are differences in suitable green manure varieties and planting patterns in different regions,and there is still a lack of supporting production and utilization technologies.It is important to clarify the effects of green manure intercropping in orchards on fruit tree and to explore the interaction mechanism between fruit trees and green manure.This is of great significance for making full use of green manure to increase orchard soil nutrients and organic matter,optimize the structure of soil microbial community,reduce diseases,promote fruit tree growth and improve the quality of fruit products.It is also conducive to the development and promotion of planting technologies for different regions,and provide reference for promoting the green ecological development of high-quality orchards in the future.