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Comparative biology of invasive rugose spiralling whitefly (RSW) Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae) was studied on three host plants viz., coconut (Cocos nucifera L), banana (Musa spp. L) and Indian shot (Canna indica) under caged as well as field conditions. The RSW life cycle was shorter on coconut as compared to that of banana and Indian shot plant. Thus, coconut is the preferred host for its growth and development with a fecundity of 49.50± 4.09 eggs and total duration of the nymphal instars being of 23.2± 1.38 days. Duration to lifestages on banana was less under field conditions as compared to that under caged conditions. These results on the comparative biology and growth will help to develop suitable IPM strategies for this invasive pest.

Laboratory and field evaluation of some insecticides (buprofezin 25 SC, pymetrozine 50 WG, flonicamid 50 WG, dinotefuran 20 SG, thiamethoxam 25 WG, profenophos 50 EC), botanical (azadirachtin 10000 ppm) and entomopathogenic fungus (Isaria fumosorosea Wize) were carried out against the invasive rugose spiralling whitefly Aleurodicus rugioperculatus Martin on banana. The results revealed that azadirachtin 10000 ppm (86.49%), dinotefuran 20 SG (82.64%), pymetrozine 50 WG (72.72%) and thiamethoxam 25 WG (79.59%) caused significant mortality of first and second instar nymphs at 2 days after treatment (DAT). Profenophos 50 EC (77.61%) and azadirachtin 10000 ppm (71.53%) were significantly effective and on par with mortality at 2 DAT of third and fourth instar nymphs. Flonicamid 50 WG was the most toxic with the least LC50 value (507.8 and 646.1) and buprofezin 25 SC was the least toxic with maximum value (1245.1 and 1752.0) for early and late instar nymphs, respectively. Profenophos 50 EC and LC50 buprofezin 25 SC also showed maximum ovicidal effect. Under field conditions, I. fumosorosea with 100% mortality was significantly superior compared to dinotefuran 20 SG (97.23%), thiamethoxam 25 WG (95.02%) and azadirachtin 10000 ppm (94.98%) at 6 DAT.

During last decade many invasive mealybugs were reported as major threat to agriculture in India. Among these, the recently introduced mealybug, Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae) was observed expanding its horizons to cotton growing areas of South Karnataka and Maharashtra. Since it is necessary to study its lifecycle, so as to identify the vulnerable stage, the present study was undertaken during 2014–15 under laboratory conditions on cotton. The results revealed that its males had a slightly longer nymphal period (22.4± 1.49 days) compared to females (20.96± 1.03 days) due to additional pupal stage. Fecundity of female ranged from 215–398 eggs/female. The pre-ovipositional, ovipositional and post-ovipositional periods lasted for 9.6± 0.93, 5.56± 0.69 and 4.12± 0.81days, respectively. Adult female lived for 25.04± 1.50 days, while its adult males lived for only 2.48± 0.49 days. The total developmental period of females lasted for 48.28± 2.12 days and in males 24.88± 1.98 days.