Papaya mealy bug has created havoc in Tamil Nadu in the past two years. It infests nearly 60 host plants including Papaya, Tapioca, Mulberry, Bhendi, Brinjal, Tomato, Turmeric, Cotton, Jatropha, Kapak, Teak, Sugarcane etc.,
Because of its damage, papaya production came down by 60 – 80 per cent. Chemical pesticides have been able to provide only temporary relief and farmers went for repeated sprayings and pesticide cocktails which resulted in ecocidal effects.
Natural enemies were considered the only last resort for management of this pest. Available natural enemies like Cryptolaemus montrouzieri and Scymnus coccivora were also not able to keep the pest population under check.
Imported varieties
The National Bureau of Agriculturally Important Insects (NBAII), Bangalore took efforts in importing three exotic papaya mealy bug parasitoids such as Acerophagus papayae, Pseudleptomastix mexicana and Anagyrus loecki from Puerto Rico during July, 2010.
NBAII, Bangalore and TNAU, Coimbatore have standardized the mass production techniques of these parasitoids. Various Research Stations, Krishi Vigyan Kendras and Colleges under TNAU started mass multiplication of these parasitoids and distributed them to farmers for field release, free of cost.
All the three tiny parasitoids are solitary, species specific, have good host searching capability and attack only papaya mealy bug.
Good result
All these three parasitoids proved highly successful in Tamil Nadu. These parasitoids especially Acerophagus papayae, established very well and brought significant control of papaya mealy bug not only on papaya, but also on other crops.
The released parasitoids should be conserved by avoiding use of chemical pesticides and maintaining alternate hosts like weed crops such as parthenium, acalypha, plumeria etc. and tree crops like kapak, teak etc. This classical biological control programme has become popular among large sections of farmers in Tamil Nadu.
(A. Suganthi, Asst Prof and S. Nanthakumar, programme co-ordinator, Krishi Vigyan Kendra, TNAU, Virinjipuram, Vellore, Tamil Nadu, Phone:0416-2272221.)
Keywords: Papaya mealy bug, papaya production, parasitoids, pesticides
Papaya mealy bug was a very serious pest last year observed in
papaya,guava,ornamentals like bougainvillea,hibiscus and olives.Affected fruits are unfit for
consumption and those consumed had bowel irritation ,omitting and loose motion.Notices
were pasted in public places not to consume pest affected fruits.One parasitoid made
available from the centre under All India Co-ordinated research project on biological control
at Kerala Agricultural University was introduced.There was no visible reduction in mealy
bugs.Meanwhile there was good rains and now the scale bug is not serious in
guava,foliages,bougainvillea and also papaya.What perturbs me is the arrival of the
pest.This is not an Indian endemic pest.Management through parasitoids (introduced) is to
be careful that the parasitoid may not turn as a pest when the present host scale bug
disappears.
Please Email the Editor