Biology and predatory potential of chrysopids on invasive coconut rugose spiralling whitefly Aleurodicus rugioperculatus Martin

Abstract

The relatively new invasive rugose spiralling whitefly (RSW) Aleurodicus rugioperculatus (Hemiptera: Aleyrodidae) has become a serious threat to oil palm, particularly coconut plantation, in southern India. Here, we report biology and foraging potential of predatory neuropteran Green lace wings Chrysoperla zastrowi sillemi (Esben-Petersen) and Mallada boninensis (Okamoto) (Chrysopidae) on against RSW. Results revealed that A. rugioperculatus served as a suitable host for the both chrysopid predators. C. z. sillemi completed its life cycle in 19.91±1.90 days with a larval (grub) period of 9.44±3.91 days and adult longevity was 24.10±1.87 days. The developmental period of M. boninensis was 22.3±2.93 days, with a larval period of 11.85±1.71 days, while the adult longevity was 19.25±1.52 day. In the laboratory experiment, all the larval stages of the predators were observed to feed on A. rugioperculatus. It was observed that the 3rd instar grub of C. zastrowi sillemi with the developmental period of 3.24±1.73 days consumed a maximum of 313.2 whiteflies (all the life stages) followed by second and 1st instar grub stages of the predator, which consumed mean number of 200.2 and 140.2 eggs and nymphs of A. rugioperculatus, respectively during their developmental period of 3.58±1.84 and 2.62±1.34 days, respectively. In the case of M. boninensis, a single grub could consume a total of 929.8 whiteflies (both eggs and nymphal stages) during its total larval period of 9.44±3.91 days.