Population structure of whitefly (Bemisia tabaci) and the link between vector dynamics and seasonal incidence of yellow mosaic disease in blackgram (Vigna mungo)

Abstract

The hemipteran pest silverleaf whitefly, Bemisia tabaci (Gennadius) (Aleyrodidae), is of high economic importance, as it infests a wide range of agricultural and horticultural crops. The pest is regarded as a cryptic species complex. In the present study, the cryptic species composition and viruliferous status of B. tabaci in association with yellow mosaic disease (YMD), caused by Mungbean yellow mosaic virus (MYMV), in blackgram [Vigna mungo (L.) Hepper (Fabaceae)], were assessed over three cropping seasons, viz., Rabi, summer, and Kharif, at three locations in Tamil Nadu, India. This study identified three cryptic B. tabaci species: (1) Asia I, (2) Asia II‐5, and (3) Asia II‐8. Asia II‐8 was the dominant species in all three seasons across locations. Despite the absence of YMD symptoms in many plants, up to 73% of whiteflies sampled from YMD‐resistant and susceptible blackgram cultivars were MYMV‐viruliferous. This suggests that the YMD incidence of blackgram does not directly associate with viruliferous whitefly populations in the field.