Identification of Rugose Spiralling Whitefly Infesting Host Plants in Bangladesh and Assessment of Its Damage Severity

Abstract

The rugose spiraling whitefly (RSW), Aleurodicus rugioperculatus (Aleyrodiade: Hemiptera) is an invasive insect pest and it was first identified in Bangladesh in 2019 on coconut plants. A baseline survey study was conducted in Bangladesh to identify the RSW-infesting geographical locations, host plants as well as to assess the damage severity. The duration of the survey period was 8 months from May to December 2021. Based on our survey results, we report that RSW has invaded all over Bangladesh with low to very severe infestation level. The highest infestation was noticed in west, southwest and northeast regions while comparatively lower infestation was found in south, southeastern and central part of the country. It was evident from this study that both border and non-border districts were affected almost equally by this insect pest. During the survey period, sixty onehost plants were identified throughout country where 49.18% werefruit plant species, 21.31% ornamentals and flowers, 8.19% field crops, 8.19% forests and 13.13% other species. Among the host plants, very severe infestation was noticed on coconut where 85.72% native and 81.23% dwarf coconut plants were found to be infested by RSW. Results also showed that comparatively lower leaflet infestation, low leaf area encrustation by sooty mould fungus and low abundances of adult RSW were found in dwarf coconut plants than that of native. After coconut, next infestation severity was observed on banana (low to severe) and guava (low to medium) although the extent of damage varied from district to districts. On the other hand, low infestation was found on the rest of the host plants under different plant groups viz. forests, ornamentals, flowers, field crops, cash crops etc.