引入小麦秸秆抑制番茄根结线虫病

Controlling tomato root-knot nematode disease by incorporating winter wheat straw to soil

为了研究引入秸秆碳源对土壤根结线虫(Meloidogyne spp.)病害的抑制效果,以番茄为供试作物,设置3个梯度的小麦秸秆添加量进行了为期6个月的室内盆栽试验。结果表明:引入小麦秸秆能够抑制根结线虫病害的发生,但添加秸秆量过多会对番茄的生长产生负面作用。以华北农田小麦秸秆还田模式平均输入量为基本单位N,秸秆添加量为1N(2.08g/kg)、2N(4.16g/kg)、4N(8.32g/kg)时对根结线虫病的抑制率分别是:51.4%,94.0%,39.5%;当秸秆添加量为1N、2N时,番茄的株高、茎粗、开花率等指标没有明显下降,但当秸秆添加量升高至4N时,这些指标均明显下降。引入小麦秸秆后,土壤线虫群落结构发生了变化,植食性线虫的比例均有所下降,而食细菌、食真菌和杂食捕食性线虫的比例均有所上升。1N,2N,4N3个处理植食性线虫的比例分别下降了17.6%,97.3%和2.0%,而食细菌线虫的比例分别上升了100.5%,189.7%和117.8%,其中2N处理的线虫群落结构变化幅度最大;食真菌线虫的比例在4N处理中显著上升,增长率为350%,而杂食捕食性线虫则在1N处理中明显上升,增长率为66.7%。综合番茄生长指标、对根结线虫抑制率及土壤线虫群落结构变化3方面的结果,添加秸秆量为2N时对番茄根结线虫病的抑制效果最好。

In order to understand the controlling effect of winter wheat straw incorporated into soil on root-knot nematode disease（RKN,Meloidogyne spp.）,an in-door pot experiment was conducted in greenhouse for six months,with three treatments of different addition of wheat straw into the soil and tomato was taken as the experimental crop.The results indicated that RKN could be suppressed by adding wheat straw into the soil,and the suppression rate of RKN in the three treatments of 1N（straw 2.08g/kg soil）,2N（straw 4.16 g/kg soil） and 4N（straw 8.32 g/kg soil） were 51.4%,94.0%,39.5% respectively.However,over dose of straw input would cause negative effect on tomato growth.The plant height,stalk diameter and flowering rate significantly decreased at the straw addition of 8.32 g/kg soil（4N）,but decreased much less at the straw addition of 1N（straw 2.08g/kg soil） and 2N（straw 4.16 g/kg soil）.The results also showed that the soil nematode community changed after the introduction of wheat straw carbon resources,with herbivores nematodes decreasing and bacterivores,fungivores and omnivores-predator nematodes increasing in all treatments.In 1N,2N and 4N treatments,the herbivores nematodes decreased 17.6%,97.3% and 2.0%,respectively;and the bacterivores nematodes increased 100.5%,189.7% and 117.8%,respectively.For these two dominant functional groups,the 2N treatment caused the biggest change of soil nematode community structure.In 4N treatment,fungivores nematodes increased 350%,showing a remarkable increment direction;while omnivores-predator nematodes increased the most obviously in 1N treatment,which was 66.7%.Considering tomato growth situation,suppression rate on RKN and changes of soil nematode community structure,the controlling effect of addition winter wheat straw into soil on RKN was the best at the straw addition of 2N（straw 4.16 g/kg soil）.