Optimizing the mass rearing technique for rugose spiraling whitefly (Aleurodicus rugioperculatus) and its parasitoid (Encarsia guadeloupae) under laboratory conditions.

Abstract

The rugose spiralling whitefly (RSW) Aleurodicus rugioperculatus is a serious pest that causes substantial economic losses in Sri Lankan coconut plantations. Chemical based approaches have been commonly employed to manage severe whitefly infestations; but, the emergence of biocontrol agents provides a promising alternative. Encarsia guadeloupae has been identified as the most common natural enemy for RSW. The study initiated taxonomic identification for RSW and E. guadeloupae, followed by an investigation into their mass rearing on six host plant species viz Coconut (Cocos nucifera), Banana (Musa spp), Fan palm (Livistona chinensis), Poinsettia (Euphorbia pulcherrima), Canna (Canna indica) and Ground nut (Arachis hypogaea) under controlled laboratory conditions. The primary objective was to determine the most suitable host plant species for rearing RSW and promoting the growth and development of E. guadeloupae. In order to evaluate the suitability of different host plants, parameters such as oviposition preference, life cycle development, and percentage of parasitism were examined. According to the results, fecundity estimates indicated that the oviposition preference of RSW was highest on coconut followed by banana. RSW successfully completed its lifecycle on all host plants except groundnut. Both coconut and banana proved to be conducive to the growth and development of E. guadeloupae. Parasitism levels of E. guadeloupae did not exhibit significance in whiteflyinfested coconut (49.86%) and banana (52.71%). Based on our findings, coconut was identified as the most suitable host plant for mass raring of RSW. Additionally, both coconut and banana were effective in promoting the growth and development of E. guadeloupae. These findings would contribute to the development of sustainable and effective biological control practices for RSW in coconut plantations.