环境因子对作物根围线虫种类及数量的影响

从上海郊区的西甜瓜种植棚取样,包括4个区6种土壤类型,即黄泥、青紫泥、青黄泥、黄小粉土、潮沙泥和沟干泥。结果表明,仅在青黄泥、青紫泥和黄小粉土中发现植物寄生性线虫,其中滑刃线虫在3种土壤中都有分布,且所占比例较高;对植物危害性较大的螺旋线虫和根结线虫,只在黄小粉土中有分布,所占总线虫量的比例都低于2%;青黄泥、黄泥和潮沙泥中线虫数较少,黄小粉土中线虫数相对较高;线虫的季节性波动有2个高峰期,分别为4～6和5～7月,且后一个高峰期比前一个要高;作物换茬轮作方式不仅可大幅降低线虫量,而且可抑制高峰期的出现;高温对线虫生长也有一定的抑制作用,土壤含水量低有利于线虫生长。

Effect of Environment Factor on Crop Root Nematode Community and Fluctuation

The experimental sampling from watermelon and muskmelon were planted in hothouse in suburban area of Shanghai,with four areas and six soil types: yellow soil,green purple soil,green yellow soil,yellow powder soil,the tide sand soil and ditches.It was stated that parasitic nematodes was only found in three soil types.And this three soils all had aphelenchus nematode and it was high proportion in total population.The season fluctuations of nematodes had two peaks,one appeared in April and June,and another,in May and July.And the later peak was higher than the former.Through rotation,the populations of nematodes can be greatly reduced and the peak can be restrained.The high temperature restrained the nematodes growth.