柑桔半穿刺线虫生物学研究

半穿刺线虫Tylenchulus semipenetrans年发生6—7代,完成一代需28—45d。卵在25℃时历期13—14d,28℃为9—10.5d;二龄幼虫发育至成虫25℃需14.5—19d,在潮湿土中30℃存活70—80d,25℃存活182—190d。此线虫以二龄幼虫从寄主幼根伸长区侵入,一个侵染点一般只有1条幼虫。在土中,二龄幼虫主要分布于0—45cm土层,最深达90cm,雌成虫多分布于0—30cm深处须根上,数量消长与柑桔物候期有关,沙含量61%—87%、pH值6—8和有机质丰富的土中线虫密度大,植株受害重。     

Evaluation of methyl iodide as a soil fumigant in container and small field plot studies

Methyl iodide was evaluated as a soil fumigant as a potential replacement for the widely used soil fumigant methyl bromide. In container trials, methyl iodide was significantly more effective than methyl bromide against the plant parasitic nematodes Meloidogyne incognita, Heterodera schachtii and Tylenchulus semipenetrans and the plant pathogenic fungus Rhizoctonia solani. In small field plots, soil populations of root-knot nematodes were no longer detected after methyl iodide fumigation at an application rate of 112 kg ha^-1. However, after growing a susceptible lima bean host for two months, substantial root-knot galling occurred, while Rhizobium nodulation was absent. At 168 kg ha^-1 of methyl iodide, root-knot galling was reduced to less than 1%, and no Pythium propagules were recovered on selective detection media. These efficacy data support the conclusion that methyl iodide is a likely candidate for replacing methyl bromide as a soil fumigant. © 1998 SCI.     

土壤添加剂防治柑桔慢衰线虫病的研究

 用土壤添加剂在网室和田间对柑桔慢衰线虫病(Tylenchulus semipenetrans)的防效和植株生长及产量的影响进行了研究,结果表明,网室盆栽防效为82.5%,株高和植株鲜重较对照分别增加81.0%和152.6%;田间防效为75.2%,株年均抽梢量和单株平均产量分别增加80.4%和50.6%,土壤中主要天敌线虫和菌类数量较对照也有明显增加.