番茄根结线虫分离和苗期接种方法研究

Study on the method of separating root-knot nematodes and inoculating to tomato seedlings

通过5年番茄栽培地的根结线虫发病状况调查，得出蔬菜栽培地的根结线虫发病率为90％-100％。采集发病株根系及其附着的根系土，利用蔗糖高渗溶液离心法与分离筛法分离，获得病原线虫3种虫态的虫体。接种不同虫态的分离物于培养的番茄幼苗，培养56d后，调查结果显示：已分化并具有卵雏形的雌虫所产生根结和卵块团的数量极少，缺乏侵染性；接种虫卵和幼虫对苗期番茄根系具有侵染性，但形成根结时间不同，接种幼虫后10d可见根结雏形，同时接种的虫卵，16d可见根结雏形，病圃土则需17d；接种J2幼虫后，苗期番茄单株平均形成卵块团数为48．1个，虫卵和病圃土则约有4．5个，表明接种幼虫是测试植物对根结线虫敏感性的有效虫态。

After investigating 5 times the roots of tomato plants in cultivating vegetable land during 5 years,they were infected 90 % - 100 % by root-knot nematodes. The roots and soil of sticking on them were collected. Nematodes from their washed solution and mud were extracted by means of sugar solution centrifuge and sieve wash. The ouveniles,big females and eggs were obtained. Inoculated them separately to tomato seedlings. The results showed that the big females could not infect tomato root,the rudiment of galling appearred after 10 days by inoculating juveniles, however, it appeared separately 16 days and 17 days after inoculated by eggs or soil from cultivating tomato land. And the average number of galls and egg-masses on each plant root systems was different. The average number was 48.1 by inoculated juveniles ,about 4.5 by inoculated eggs or the soil. The results indicated that it was effective method by using of juveniles to inoculate.