Sands (W. N.). Native Food Plants and Feeding Habits of the Cotton 

 Stainer in St. Vincent. — Agric. News, Barbados, xv, nos. 369 & 

 370, 17th June & 1st July 1916, pp. 202-203 & 218. 



' Injury to cotton by Dysdercus delauneyi, Leth. (cotton stainer) in 

 St. Vincent has been followed during the past three years by a fungus 

 disease of the bolls which has resulted in serious loss. Investigations 

 have been carried out relating to the feeding habits and native host 

 plants of the bug, in order to devise new methods of control other than 

 by hand-picking. Cotton plants are usually pulled up and burned by 

 the end of February and the new crop is planted in May. During the 

 interval the insects feed on flowers of Mangifera indica (mango), Eujpa- 

 toriuni odoratum, Cordia cylindrostachys (black sage), and Moringa 

 pterygosperma (horse radish tree), on the fruit of Hibiscus escidentus 

 (okra) and Monnordica charantia, and on secretions of scale-insects, but 

 do not seem able to breed on these hosts. Eriodendron anfractuosiim 

 (silk-cotton tree) and Thespesia popidnea (John Bull tree) are more im- 

 portant than the above hosts, in that they form breeding places and thus 

 furnish a supply of insects for the infestation of the new cotton crop. 

 E. a^ifmctuosum occurs chiefly in the Leeward district near the coast. 

 Mal^ and female insects appear on the trees at the end of February, 

 a,t the time when the young bolls begin to swell. Young insects are 

 found at the beginning of April on damaged bolls both on the tree and 

 on the ground, and later occur on seeds on the ground. The latter 

 form a source of food until the cotton crop is ready. The examination 

 of injured bolls has failed to show the presence of the fungus causing 

 internal boll disease. E. anfractuosum does not flower every year and 

 is therefore only periodically a source of danger. It should either be 

 destroyed or pruned back as soon as the flowers are seen. T. populnea 

 occurs extensively in a part of the Windward district, and in smaller 

 numbers in the Leeward district. Breeding takes place very freely on 

 this tree during April. It should therefore be treated in the same way 

 as the previous species. Natural enemies of the cotton stainer include 

 several birds and a mite;" ( :gnmvTq^ io :'nrr,tx£ir. 



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Cacao Thrips and Die-Back in' St. Vincent. — Agric. Neivs, Barbados, 



XV, nos. 369 & 370, 17th June & 1st July 1916, pp. 206^207 & 

 i)iu: 222-223. H! J ).njz^ o ondoT 



'^'>f . , ■ . . . : ■■■..■. . --r- ;.-•- 



A number of cacao estates in St. Vincent were visited by the Ento- 

 mologist and Mycologist for the purpose of investigating the status of 

 Heliothrips rubrocinctus (cacao thrips) in these districts. On one estate, 

 two periods of abundance of thrips occurred during the year, one in 

 April and May, in the dry season, and the other in September and 

 October, in the wet season. Two conditions among unhealthy or dead 

 trees were observed : — (1) trees which were attacked by a root disease 

 due to the fungus Rosellina sp. ; (2) trees which were dead or dying 

 and had been severely attacked by thrips, the dead branches being 

 infested with Diplodia (die-back fungus). This disease was also found 

 both in young and mature trees, and trees thus affected were very 

 susceptible to injury by thrips. 



Certain remedial measures are suggested for trees suffering from 

 Diplodia. Shade plants, such as banana, tannia and Gliricidia should 



