Papaya mealy bug is an exotic pest recently invading India. Its extensive spread to neighbouring countries is also reported.
The pest sucks the sap from tender shoot and leaves resulted with deterioration in leaf quality followed by premature drop and stunted growth of plants.
The black sooty mould developed on the honey dew excreted by pest, pollutes the entire garden and makes the leaves unfit for feeding silkworms, in case of severe infestation
High reproduction
The pest has high reproductive potential, i.e. one female can lay up to 600 eggs, and the progeny completes the lifecycle in a shortly less than a month period.
Dense, waxy secretions around the body protect the pest from adverse environmental conditions and pesticides. Papaya mealybug remains as a minor pest in many countries due to presence of adequate population of its natural enemies.
Whereas, indiscriminate application of toxic chemical destroys the natural enemy complex and the pest flares-up after developing resistance to most of the pesticides. The toxic chemicals also cause health hazards to humans and other beneficial organisms including silkworms.
Farmers prefer mainly chemical measures to obtain instant results without perceiving their adverse impact. Hence, emphasis on integrated application of following non-chemical practices is also a need of hour for effective control.
Control
Collection and burning of infested plant parts, pruned stems, and the weeds harbouring the pest.
Multiple cropping must be avoided to prevent shifting of the pest to pruned gardens at the time of sprouting.
Using rain guns or sprinklers instead of flood irrigation helps control the pest.
Spray of strong jet of water in infested garden by diverting a portion of irrigation water through small hose dislodges and washes out the pest population.
Release of predators such as Cryptolaemus montrouzieri Scymnus sp , Spalgis epius and the parasitoids viz. Acerophagus papayae, Anagyrus loecki and A. californicus is found promising. Suitable sticking agent should be mixed with the pesticide solution and the plants should be drenched thoroughly for high efficacy.
R. Balakrishna, Mukund V. Kirsur & N. Sakthivel
Regional Sericultural Research Station, SalemCentral Sericultural Research & Training InstituteMysore & Research Extension Center, Central Silk Board, Srivilliputtur, Tamil Nadu
