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THE AGRICULTUEAL NEWS. 



Maed! 2i. 1917. 



FUNGUS NOTES. 



PRELIMINARY TRIALS WITH THE 

 CACAO THRIPS FUNGUS. 



(Cultures of Sporotri'c/i.uiii f/lo/iulifertnn, obtained from 

 jiarasitized thrips collected by xVIr. W. N. Sands in St. Vincent 

 -a.H previously announced {Agncuftwal News, Vol. XV. 

 p. 430), were forwarded in December from this Office to 

 the Superintendent of Agriculture in Grenada for trial. 

 Mr. Moore's report has now been received. 



The first application was made by spraying the spores 

 suspended in milk-warm water on to several suckers in the 

 cacao plot at the Botanic Gardens. The weather conditions 

 in the period which followed were considered to be too dry 

 for .succe.ssful fungus development, and the proportion of 

 nymphs to adult thrips was very small. One thrips parasi- 

 tized by the fungus was found four days after inoculation, 

 but observations continued for a month failed to reveal the 

 ^■resence of any further examples, 



The next trial was carried out on cacao plants in boxes, 

 vhich in order to maintain a humid atmosphere were placed 

 in a cotton-screened enclosure in the nursery. Thrips in all 

 stages were introduced en the plants. Some days later, 

 Lalf the plants (2 boxes) were sprayed with the fungus 

 spores. Soon afterwards (time not given) dead nymphs 

 were observed on these plants, and twelve specimens were 

 microscopically examined and found to be parasitized by the 

 fungus. On the following day a careful count was made which 

 showed 112 parasitized nyuiphs Later a number of parasi- 

 tized adults were found. Specimens of the dead insects 

 were forwarded to the Imperial Commissioner of Agriculture, 

 and the identity of the recovered fungu.< was confirmed by 

 the writer. 



The other two enclosed boxes were at the same time 

 dusted with spores of the gretn muscardine fungus, Metar- 

 T/n:ium avisopliac. One adult thrips was found dead and 

 covered with a greyish green fungus, but the specimen 

 was lo.st before it could be examined. 



It is proposed to repeat tlie.se experiments, and to make 

 field trials in humid .situations when the wet season infesta- 

 tion begins. 



NEW RECORDS OF ENTOMOGENOUS 

 FUNGI IN BARBADOS 



In the course of a recent visit to one of the deep gullies 

 "which occur in the curni limestone of Barbados, the following 

 fungus parasites of lavfci,- were collected by the writer: 

 Vertirillium lieteroihitUnn. on a species of citrus white fly, 

 Asr/tersonia {mheivi ?) oi. slar-scHln i Vinsonia), and Oplnonec- 

 iria coccicola on piirplf ^cp!e (Lepidosaphes). All occurred 

 commonly on the leaves of 'ime trte.-^ growing on the floor of 

 tlie gully. 



The first specie.s. '.vh'rh is the one known as the cinnamon 

 fungus in Florida, d' c.h i; • ;iiipe:i.r lo have been previously 

 recorded in the West, Inrii. - ^ nih ''f Porto Kico. The second 

 is common in the tsci.. -:ci.iicl>; has been known to the 

 ■writer in its prese iiv '.':■ -.. '.n Harbados for three or four 

 jears, and is rather ifT-i'iivi- dw a pa asite. The third species 

 is common, and veiy u.ief ^1 in Dominica and St. Lucia, and 

 occurs in Grenada BnJ St Vincent. This appears to be the 

 ^rst record of its pre.sencc in Barbados. 



WN. 



Growing Canavalias for Food in the West 



Indies. — Considerable West Indian interest is being shown 

 in the cultivation of various species of beans of the genus 

 Canavalia Both C. r/ladiata, the Sword bean, and '-'. ensi- 

 tormis, the Horse bean, are valuable green dressings, and 

 there is no doubt that both these beans could he made use 

 of for food purposes. At pre.sent they are regarded with 

 some suspicion on account of the existing notion that these 

 beans are poisonous or wholesome. In Porto Bico a trial 

 has been made with Cavavilta incervn. This bean is 

 cultivated as a vegetable in a number of Asiatic countries 

 but its growth has been poor in Porto Piico compared with 

 that of the brown- and purple-seeded types of C. gladiafa, or 

 white-seeded C. ' iisiformis. In regard to the cultivation of 

 this latter species in the British West Indies, Mr. A J. Brooks, 

 Agricultural Superintendent, St. Lucia, states that it is very 

 desirable that the question of the poisonous character of these 

 beans should be cleared up definitely, as the plant is capible 

 of supplying a large quantity of food material in St. Lucia. 

 The same holds good in the case of other islands too. It 

 may be pointed out that the wholesome character of C. i/ladi- 

 ata has been definitely established both in Barbados and 

 Trinidad, where this bean has been regularly consumed 

 by several well-known residents. There is little doubt 

 that the reputation which C. enn/ormis bears in the popular 

 mind is equally unfounded; in fact most of the published 

 statements make definite reference to the wholesome 

 nature of thi.s pirticuUr bean. Mr. Brooks's notes con- 

 cerning cultivation are as follows. 



Sown 2 feet .apart under favourable conditions an acre 

 will produce 10,000 good plants bearing an average of twelve 

 pods each. Each pod contains an average of from ten to 

 twelve large beans. On rich land, sixteen to twenty beans 

 per pod have been obtained. 



The average yield per acre is something over one million 

 mature beans weighing, when thoroughly dried suitable for 

 manufacturing into meal, 4,000 tb. per acre. 



The plant when cut at flowering period and before pods 

 have commenced to form, has during extended trials at 

 Reunion given Hi tons of fresh green manure per acre 

 excluisve of roots, the plants being chopped down with hoes. 



The different economic uses and possibilities of the 

 .seaweeds are dealt with at length in the Journal of t lie New 

 Yor/i- Bjtanical Garden for January 1917. The statement is 

 made that, as-suming that two crops a year of kelp could be 

 harvested on the (_'alifornia coast, a return of 59,300,000 

 tons of fresh kelp, equivalent to 2,266,000 tons of potassium 

 chloride could be obtained. It is maintained that the giant || 

 kelps of the Pacific Coast, harvested to a depth of 6 feet, 

 could perennially yield an annual output of pota.ssium 

 chloride about six times the equivalent of the potassium .salts 

 now imported into the United States Besides their use as 

 manure, the seaweeds are used for a variety of other purposes 

 in different parts of the world. They yield iodine, and in 

 Japan and Hawaii they form an important item of the diet 

 of the people. Other seaweeds are u.sed as a source of glue. 



