甘肃岷县当归茎线虫病发生情况调查分析

2014年11月对甘肃省当归主产区岷县的5个乡镇42块当归田采用随机取样方法进行了系统调查,以了解当归茎线虫病的发生分布情况。调查结果表明,当归茎线虫病田间病株率达到25%~79%,病情指数达15.8~68.0,其中,以梅川镇梅川村发病最严重,发病率达79%,病情指数达68.0;在不同土壤深度、不同土壤类型、不同茬口作物根际土壤中均有腐烂茎线虫分布,但群体密度不同。以5.0~10cm土层分布比例较大,每100g达230头;以黑土中病原线虫密度较大,每100g达1 102头,与黄土和沙壤土相比线虫密度差异显著(P0.05);不同茬口作物中以黄芪茬口病原线虫密度较大,每100g达590头,与马铃薯、大豆、小麦茬口相比线虫密度差异均显著(P0.05)。

A survey of the Ditylenchus destructor on angelica in Min County of Gansu Province

Angelica stem nematode (Ditylenchus destructor )disease is one of the most important nematodia-sis of Chinese angelica in Gansu Province.In November 2014,with the random sampling,a survey covered 42 fields in 5 villages,where is the main angelica production area in Min County of Gansu was conducted to detect the occurrence and distribution of angelica stem nematode.The resulted showed that incidence of Ditylenchus destructor was 25% to 79%,disease index reaced from 15.8 to 68,the most serious disease area was Mei Chuan Village in Mei Chuan Township,where the incidence rate reached to 79%,the disease index reached to 68.D.de-structor was distributed at different soil depths in various type soils,as well as different fore-rotating crops fileds.However,the population densities were different,D .destructors were mainly distributed in 5 ~ 10 cm of soils,where the number of nematodes reached 230 in each 100 g soil.The results also showed that the highest nematode population densities ditributed in black soil,the number of nematodes were 1 102 in each 100 g soil,the density of nematodes had significant difference compared with loess and sandy loam (P < 0.05 ).In different fore-rotating crops,the highest nematode population densities ditributed in astragalus,the number of nematodes were 590 in each 100g soil,compared with the stubble crops of potato,soybean,wheat,the density of nematodes had significant difference(P <0.05).