R.N. Singha*, A. Tikadera & Beera Saratchandraa
aCentral Silk Board, Bangalore 560068, Karnataka,India
Received 4th January, 2012; Revised 26th February, 2012
Abstract : The papaya mealybug (PM), Paracoccus marginatus Williams and Granara de Willink, (Hemiptera:Pseudococcidae), is a major pest of mulberry plants in south India. Apart from common predators, several parasitoids viz. Acerophagus papayae (Noyes and Schauff), Anagyrus loecki (Noyes and Menezes), Anagyrus californicus Compere, and Pseudaphycus sp. have been reported to be highly potential. Recently another parasitoids identified as Pseudleptomastix mexicana (Noyes and Schauff) has been reported to be highly effective at field level. All four species of parasitoids prefers to attack second and third instars of P. marginatus. However, Acerophagus sp. emerged as the dominant parasitoid species. The parasitoids Anagyrus loecki Noyes, Pseudleptomastix mexicana Noyes and Schauff, and Acerophagus papayae Noyes and Schauff (Hymenoptera: Encyrtidae) were imported from Puerto Rico and field released in Tamil Nadu. Anagyrus loecki and A. papayae appear to be promising biological control agents of PM in Tamil Nadu. The reduction of the papaya mealybug population density levels below detectable levels was observed in a six-month period following the introduction of these exotic parasitoids. Following the successful implementation of a classical biological control program, the risk of this mealybug spreading to other neighboring states has been considerably reduced. Biological potential, reproductive strategy, host searching ability and sex ratio of the parasitoids have been reported. Biological suppression methods involving augmentation, conservation and utilization of natural enemies are the most important aspect and the pest population is maintained at lower level by the action of parasitoids in its natural habitat. Augmentation involves actions to increase the populations of beneficial effects of parasitoids. Augmentation through inoculative or inundative releases of parasitoid is the most direct way of increasing the numbers of these beneficial. However our limited mass rearing capability is a serious impediment to the effective implementation of augmentation programme. Suitable strategy has been evolved for mass rearing of the parasitoids. Efficient and economical mechanized rearing systems are key requirements to wide spread use of this approach to biological control. Cost efficient and effective utilization of augmentation techniques is possible and has been implemented successfully to contain the bug population. All these aspects have been discussed in detail.
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