甘肃省高寒草原牧草孢囊线虫的鉴定

2013年8月下旬,对甘肃天祝高寒草甸草原孢囊线虫发生情况进行调查,从嵩草和矮嵩草根部和根际土样中分离得到孢囊线虫。通过对孢囊和孢囊阴门锥的形态观察,初步鉴定为禾谷孢囊线虫(Heterodera avenae)。其特征为孢囊浅褐色,阔柠檬形,阴门锥双膜孔,未见阴门下桥,泡状突明显。利用通用引物AB28和TW81对其群体rDNA-ITS区进行PCR扩增和序列测定,得到ITS区序列长度为1045bp。将所测得序列在Genbank和Blast上比对,结果显示,此禾谷孢囊线虫群体与H.avenae群体相似度达99%~100%。进一步证实寄生于甘肃天祝高寒草甸草原嵩草和矮嵩草的孢囊线虫均为H.avenae,这是首次报道莎草科嵩草和矮嵩草也是禾谷孢囊线虫的寄主。

Identification of cyst nematode in alpine meadow steppe,Gansu

A survey of grass cyst nematodes in Tianzhu alpine meadow steppe,Gansu Province was conducted in August,2013.Cyst nematodes were isolated from the roots and root rhizosphere of Kobresia sp.and Kobresia humilis .The nematodes were initially identified as Heterodera avenae based on cyst characteristics,particular-ly the cyst vulva cones.The cysts were light brown,large lenmon-shaped and contained vulva cones with bifenestrate and obvious bullae and without a vulva under-bridge.The 1045 bp sequence fragment of ITS region was amplified using PCR with general primers AB28 and TW81.The similarities between these groups and H . avena were 99%-100%.Molecular analysis confirmed that the cyst nematodes isolated from Kobresia sp.and Kobresia humilis growing in Tianzhu alpine meadow steppe were H .avenae .This is the first report identifying Kobresia sp.and Kobresia humilis as hosts of H .avenae .