生姜根结线虫病原鉴定及发生规律

Pathogen identification and occurrence law of ginger root-knot nematode disease

采用田间调查、接种试验、电镜与显微镜观察以及酯酶同工酶电泳等方法,对引发生姜癞皮病的病原及发生规律进行了研究。结果表明,引起生姜癞皮病的病原为南方根结线虫 Meloidogyne incognita。该病在每年6月中旬开始发生,8、9月份危害严重。病原在生姜上一年可发生完整的4代,完成1代平均约需35天。病原主要在0～40cm 的土层内分布和危害,但具体分布情况依寄主生长状况而稍有差异。南方根结线虫繁殖速率受初始接种密度的影响也很大,当初始接种密度较低时,线虫繁殖速率较高,初始接种密度增大,繁殖速率降低,其平衡密度为每100 g 干土746.20个卵。

The pathogen and occurrence law of ginger laipi disease were studied through thefield investigation,greenhouse inoculation,light and scanning electronic microscopes and ester-ase isozyme electrophoresis.Results showed that south root-knot nematode,Meloidogyne incog-nita,was the pathogen.The disease began to occur at the middle ten days of June,and be-came severity at August and September.The nematode completed four generations in one grow-ing season.The duration each generation was about 35 days.The greatest population densitiesof the nematodes occurred in 0-40 cm layer of the soil below the surface.But distribution ofthe nematodes has a slightly difference depending on the growth of host.The reproduction rateof M.incognita was effected by initial population density dramatically,the lower initial popula-tion density,and the higher reproduction rate of M.incognita.The reproduction rate was de-creased when initial population density increasing.The balance initial population density was746.20 eggs per 100 g soil.