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RfCHARDS (R. M.). The Diseases and Pests of the Coconut Palm. — 



Agric. Bull. Fed. Malay Stales, Kuahi Lumpiir, v, no. 8-9, 

 May-June 1917, pp. 327-337. [Received 24th September 1917.] 



Oryctes rhinoceros is abundant in the Malay Peninsula. Preventive 

 measures are most important ; larvae should be collected and 

 breeding-places destroyed. Debris of coconuts should be collected 

 and destroyed regularly. Traps are not as a rule very successful, but 

 •on scrupulously clean estates they have proved of some benefit. 

 Xylotrnpes gideon (leaf beetle) should be controlled by collecting the 

 adults. Rhynchophorus ferrugineus passes through all stages of its 

 life-history on the coconut, the larval being the destructive stage 

 {see also this Review, Ser. A, v, p. 499]. The adults and larvae of the 

 Hispid, Broniispa frogatti, Sharp, are both destructive to coconuts. 

 The beetles crawl into the folded leaflets and oviposit between them, 

 the larvae and adults eating away the tissues. In the Solomon 

 Islands tobacco and soap wash is shaken into the still unfolded leaves, 

 but the only really successful method of eradication is to cut away the 

 affected leaves and burn them. The larvae of Hidari irava and 

 Erionota thrax eat away the leaflets, but both species are heavily 

 parasitised and rarely if ever survive after the second brood. Catching 

 the adult butterflies or picking off and destroying the pupae are 

 generally a sufficient remedy. Thosea cinereomarginata is commonly 

 found in the pupal stage attached to the under-side of palm-leaves ; 

 the caterpillars devour the young leaflets, but there is very seldom any 

 .serious infestation. A Psychid, Makasena sp., occurs on coconuts, but 

 is not a serious pest. 



The Zygaenid, BracJiartona catoxantha, is a serious pest, but after a 

 maximum of six generations, and frequently less, parasites have 

 multiplied to such an extent that this moth is practically exterminated ; 

 its parasites, of which the most important are a fungus, Botrytis sp., 

 and a Phorid fly, then die off and three years apparently elapse before 

 there is another serious infestation of the moth. Preventive measures 

 adopted on one plantation, which had the desired effect, consisted of 

 cutting off and burning all the lower leaves of palms which had been 

 badly eaten and on w^hich many thousands of insects were pupating. 

 As soon as the caterpillars that hatch from eggs on the under-side of 

 the leaves appeared, they were singed with torches, causing them either 

 to die or drop to the ground. As they immediately try to get back 

 by crawling along the ground and up the stems of the palms, a band 

 of tar and grease was painted on the stems about 1| ft., above the 

 ground, thousands of caterpillars being caught by this means on 

 almost every tree. They were also beaten, shaken and brushed off 

 the leaves of the palms. Comparatively few moths developed of the 

 next generation and within three months of this treatment the pest 

 had disappeared. No part of the palm but the leaves should be 

 scorched ; if the crown be injured, attack by Rhynchophorus ferrugineus 

 will probably follow. Coptotermes {Termes) gestroi occasionally causes 

 injury by boring into the tissues of the stem. Scale-insects are chiefly 

 troublesome in encouraging the sooty mould, Meliola palnuwum. 



