不同栽培条件下蔬菜塑料大棚土壤尖孢镰刀菌数量的变化

应用尖孢镰刀菌选择性培养基,调查了太湖地区不同蔬菜品种、不同栽培年限、不同栽培方式及不同土壤深度的蔬菜塑料大棚土壤中尖孢镰刀菌数量的变化情况。结果显示,栽种黄瓜的土壤中尖孢镰刀菌数量达1.6×104cfug-1干土,显著大于栽种芹菜和茄子的土壤。随着栽培年限的增加,土壤中尖孢镰刀菌数量有增加的趋势,连作4a土壤中尖孢镰刀菌数量比连作1a土壤增加了22%。与有土栽培相比,基质槽培土壤中尖孢镰刀菌数量较少,仅1.1×104cfug-1干土,基质栽培可能是国内今后蔬菜塑料大棚的发展方向之一。随着土层深度的增加,土壤中尖孢镰刀菌数量逐渐降低,尖孢镰刀菌很少从表层土向下迁移。这些结果为蔬菜塑料大棚土壤的可持续利用提供了一些初步的微生物学依据。

NUMBERS OF FUSARIUM OXYSPORUM IN DIFFERENT GREENHOUSE VEGETABLE SOILS

A Fusarium oxysporum-selective cultivation medium was used to investigate numbers of Fusarium oxysporum in soils under polytunnel greenhouse cultivation different in vegetable species,different in cultivation history,different in culture systems and different in depth.Results show that the number in the soil under cucumber was as high as 1.6×10⁴cfug^-1 dry soil,significantly higher than that in the soils under eggplant and under celery.And the number tended to increase with the years of cultivation,and was 22% higher in the soil 4 years in history than in the soil only 1 year. It was much lower in the aggregate than in the soil,being only 1.1×10×10⁴cfug^-1 dry soil. Maybe greenhouse vegetable cultivation using aggregate instead of soil is one way for the country to develop greenhouse vegetables in the future. The number of Fusarium oxysporum decreased with the increase in soil depth,indicating that Fusarium oxysporum rarely moved into deeper soil. All these findings may serve as primary microbiological bases for sustainable utilization of greenhouse vegetable soils in the future.