韭菜迟眼蕈蚊在生菜上的为害及鉴定

近年在北京郊区多个生菜基地发现根蛆为害,严重威胁生菜生产。本文对北京地区生菜根蛆的为害情况进行了调查,并利用mtDNA COⅠ分子标记和成虫形态比对对其种类进行了鉴定。结果表明:生菜根蛆在生菜苗期为害可造成死苗或植株生长矮小,在生菜成熟期亦可为害根茎外表皮,但损失不明显;分子标记鉴定结果显示生菜根蛆mtDNA COⅠ基因序列与韭菜迟眼蕈蚊的一致性为100%,生菜根蛆成虫形态特征与韭菜迟眼蕈蚊形态特征一致,可基本确定北京地区生菜根蛆为韭菜迟眼蕈蚊幼虫。本研究明确了近年在北京郊区生菜上暴发为害的根蛆为韭菜迟眼蕈蚊Bradysia odoriphaga,为生菜根蛆的绿色防控提供了科学依据。

The damage and identification of Bradysia odoriphaga on lettuce

A root maggot that damaged lettuce was observed at many lettuce production bases in Beijing in recent years,which was a serious threat to lettuce production.The damage by lettuce root maggot was investigated in lettuce field and the species of the root maggot was identified by mitochondrial cytochrome oxidase Ⅰ (mt CO Ⅰ)molecular marker and morphological characteristics of the adult.The results showed that root maggot damaged lettuce root-stem and caused lettuce plants to die or stop growing during seedling stage,and fed outer skin of rootstem during maturation stage.The similarity of mtCO Ⅰ gene sequences of lettuce root maggot and Bradysia odoriphaga was 100％.Morphological characteristics of lettuce root maggot's adult and B.odoriphaga were also similar.Therefore,the lettuce root maggot was identified to be B.odoriphaga.The above results provided theoretical basis for targeted management of lettuce root maggot.