New Records of some Pests of the Coconut Inflorescence and Developing Fruit and Their Natural Enemies in Sri Lanka

L C P Fernando,P Kanagaratnam

doi:10.4038/cocos.v5i0.2050

Abstract

A survey was carried out at Bandirippuwa Estate, Kirimetiyana Estate and at IsolatedSeed Garden, Rajakadaluwa for the pests of coconut inflorescence and developing fruits.The mite, Dolichotetranychus sp. (Tenuipalpidae) which lives beneath the perianthand feeds on the epicarp, causes considerable damage to the developing fruit. Bi-monthlyobservations on the intensity of infestation of nuts among different forms of coconutindicated a significant difference among forms in their susceptibility to mite damage.Pseudococcus cocotis (Maskell) (Pseudococcidae), Pseudococcus citriculus Green(Pseudococcidae) and Planococcus lilacinus (Cockereli) (Pseudococcidae), when feedingin large numbers on the peduncle, cause button nut shedding and drying up of the inflorescence.The parasitoids and predators of these mealybugs recorded for the first timein Sri Lanka are Promuscidea unfasciativentris Girault (Aphelinidae) Platygaster sp.(Platygastridae), Anagyrus sp. nr. pseudococci (Girault) (Encyrtidae) Coccodiplosis sp.(Cecidomyiidae), Cryptogonus bryanti Kapur (Coccinellidae) and Pseudoscymnus sp.(Coccinellidae).Several species of scale insects namely, Coccus hesperidum (Linnaeus) (Coccidae)Aulacaspis sp. (Diaspididae), Pseudaulacaspis cockerelli (Cooley) (Diaspididae), Aonidiellaorientalis (Newstead) (Diaspididae), and Pinnaspis strachani (Cooley) (Diaspididae)are recorded as minor pests of the developing fruits of coconut. Coccophagus silvestriiCompere (Aphelinidae), Scymnus sp. (Coccinellidae), Pseudoscymnus sp. (Coccinellidae)Telsimia ceylonica (Weise) (Coccinellidae), Cryptogonus bryanti Kapur (Coccinellidae)and Cybocephalus sp. (Nitidulidae) are recorded as their parasitoids and predators.These natural enemies are probably responsible for the control of these pests in thefield.doi: 10.4038/cocos.v5i0.2050COCOS 1987 Vol.5 39-42

Highlights

The coconut palm produces a large number of female flowers i n each inflorescence but not all of them develop into mature fruits
T h e caterpillars of Batrachedra arenosella Walker (Lepidoptera, Gelechiidae) and Tirathaba spp. (Lepidoptera, Pyralidae), the bugs Pseudotheraptus wayi Brown (Hemiptera, Coreidae), Amblypelta cocophaga China (Hemiptera, Coreidae) and Axiagastus cambelli Distant (Hemiptera, Pentatomidae) and the mite Eriophyes gurreronis (Acarina, Eriophyidae) are the best known pests of the inflorescence and nuts
The feeding punctures made by the bugs, Pseudotheraptus wayi, Amblypelta cocophaga and Axiagastus cambelli cause deformity and premature nut fall

Summary

INTRODUCTION

The coconut palm produces a large number of female flowers i n each inflorescence but not all of them develop into mature fruits. The feeding punctures made by the bugs, Pseudotheraptus wayi, Amblypelta cocophaga and Axiagastus cambelli cause deformity and premature nut fall. The eriophyid mite which lives under the perianth of developing fruits causes deformity and immature nut fall It has been recorded from Ivory Coast, West Africa and Central and South America. In Sri Lanka preliminary work on the survey and identification of mites, mealybugs and moths associated with the coconut inflorescence was carried out in 1981 (Kanagaratnam et/al., 1981). This stimulated further studies with regard to the distribution of pests, degree of damage and the occurrence of natural enemies. This study was carried out in the North Western Province at three selected locations: Bandirippuwa Estate, Lunuwila, Kirimetiyana Estate, Lunuwila and Isolated Seed Garden, Rajakadaluwa

THE TEXT

Findings

ParasitoidlPredator Anagyrus pseudococci