湖北襄阳禾谷孢囊线虫(Heterodera avenae)生活世代及发生动态研究

Study on Life Cycle and Infection Dynamics of Cereal Cyst Nematode( Heterodera avenae) in Xiangyang City

调查了湖北省禾谷孢囊线虫(Heterodera avenae)病的分布。在襄阳市重病田采样观察了禾谷孢囊线虫不同龄期的形态,研究了不同龄期线虫的发生动态。结果表明,禾谷孢囊线虫在襄阳、天门、潜江、钟祥、汉川都有发生,以襄阳最多,平均每100 mL土样含有效孢囊12.5个。在小麦播种后20 d就有2龄幼虫侵入根部,播种后143 d根内幼虫数量达到顶峰。入侵的幼虫在根内定居取食为害,在播种后158 d发育成白雌虫而露出根外,在播种后174 d白雌虫数量达最高峰。

The occurrence and distribution of cereal cyst nematode （CCN） （ Heterodera avenae） were investigated in Hubei province. Through sampling in seriously -diseased wheat field in Xiangyang city, we observed the morphology of H. avenae at dif- ferent developmental stages, and studied its population dynamics. The results showed that this nematode distributed in Xiangyang, Tianmen, Qianjiang, Zhongxiang and Hanchuan. The most serious CCN disease occurred in Xiangyang, in which there were 12.5 living cysts in 100 mL soil sample. The 2 - instar larvae of CCN began to intrude into the young wheat roots on the 20th day after so- wing, and the larvae density in the roots reached a peak on the 143rd day after sowing. The larvae in wheat roots fed, did harm, and developed to white females on the 158th day after sowing. The developed white female came out from wheat roots, and its density reached the maximum on the 174th day after sowing.