安徽颍上县禾谷类孢囊线虫发生与危害

Occurrence of and damages caused by the cereal cyst nematode Heterodera avenae in Yingshang County of Anhui Province

为了解安徽皖北麦区及颍上县禾谷类孢囊线虫(cereal cyst nematode,CCN)发生和危害情况,用"zig-zag"法在皖北不同麦区采集小麦根际土样60份,利用Fenwick&Oostenbrink法分离CCN孢囊,统计卵密度发生频度。依据孢囊阴门锥等形态特征,鉴定颍上县CCN种类。利用扩散系数法判断CCN田间平面分布型,利用系统观察法,动态监测小麦生长季节0～300mm土层的2龄幼虫(J2)虫口变化。通过酸性品红染色方法监测早期侵染;选择CCN密度中等田块,以涕灭威作播前土壤处理,比较‘泛麦5’等品种的药剂处理间的株高和产量差异。结果表明,在皖北麦区,62%的田块CCN卵发生密度为1～10个/g土;经鉴定发生在颍上县的CCN为禾谷孢囊线虫(Heterodera avenae),颍上黄桥镇双楼村禾谷孢囊线虫在田间为块状分布;在颍上监测到J2对小麦侵染的最早时间在3月18日,当感染田块卵密度在2.5～20.5个/g土时,产量损失为9.8%～14.9%,其中‘泛麦5’产量损失显著,达14.9%。

Totally 60 soil samples were collected by ＇zig-zag＇ method from different wheat areas in north Anhui Province to investigate wheat cereal cyst nematode（CCN） occurrence and wheat damage caused by CCN.Occurrence frequency of egg density was assessed based on egg density of cysts separated by Fenwick Oostenbrink method.CCN occurred at Yingshang wheat area was identified according to morphological characteristics of cyst vulva cone,and J2.Field plain distribution type of CCN was determined by disperse coefficient method,and J2 population of CCN in soil depth of 0-300 mm was dynamically monitored during wheat growing season by systematic observations.Early infection was monitored by acid fuchsin staining method;differences of plant height and yield between aldicarb-control plots with soil treatment before sowing and non-control plots were compared on a selective field with medium egg density of CCN.The results showed that occurrence frequency of the egg density ranging from 1 egg/g soils to 10 egg/g soils was 62% in north Anhui wheat area.CCN occurred in Yingshang was identified as Heterodera avenae,and field distribution in Shuanglou of Huangqiao in Yinshang County belonged to cluster type.The earliest infection of J2 in wheat root system was observed on 18 March in the test year,and yield loss caused by H.avenae ranged between 9.8%-14.9% when egg density ranged from 2.5-20.5 egg/g soils.＇Fanmai-5＇ yield lost significantly by 14.9%.