30 



THE AGRICULTURAL NEWS 



Januaey 27, 1911 



PLANT DISEASES. 



THE STATUS AND TREATMENT OF 

 COCO-NUT BUD-ROT. 



Coconut plantations in the Lesser Antilles have hitherto 

 been small and scattered. In response to the increased atten- 

 tion directed towards coco-nut products during the last few 

 years, and the prospects of a permanent and increasing demand, 

 a number of areas of considerable size have been or are being 

 put under this crop. 



While a great, deal of necessarily slow botanical investi- 

 gation is required before coconut cultivation can be regarded 

 as satisfactory from the point of view of scientific agriculture, 

 there appears to be no reason why adequate returns should 

 not be generally achieved, provided only that the bud-rot 

 disease can be avoided or kept in control. 



It may therefore serve a useful purpose at this stage to 

 give in a form convenient for reference, information as to the 

 symptoms of the disease and the treatment to be applied. 

 The receipt of pamphlets from Cuba and .Tamaica contain- 

 ing condensed instructions on tbe.se matters enables this to be 

 done with the benefit of the larger experience attained in 

 these two islands. 



PRESENT DISTRIBUTION. 



As a preliminary it will be of interest to refer to 

 a pamphlet by Mr. John 1!. Johnston, dated June 191(1, 

 dealing with the present status of the disease and affording 

 data as to the progress of the disease in various districts 

 during the last ten or fifteen years. 



The most complete information refers to Cuba. Some 

 time previous to 1886 the disease destroyed the hitherto 

 flourishing coconut groves in Matanzas, and now in the 

 western half of the island which includes that province, it is 

 almost impossible to bring coco-nut trees into bearing. They 

 ate very commonly planted for ornament and usually do well 

 for five or six years, but almost invariably die about that age 

 with all the symptoms of bud-rot. In the district of 

 Baracoa, formerly a great centre for coco-nut production, the 

 disease, vphich is said to have appeared as far back as 

 1880, has worked havoc during the last twenty years, and is 

 reported to have reduced exports from 24 millions to 4 

 millions. 



In Jamaica heavy losses weie experienced in certain 

 districts in the period 1891-1910. Legislation compelling the 

 burning of diseased trees was adopted in 1911, and during the 

 last few years lo.sses from this disease have been small. 

 A serious outbreak was reported to have occurred in the 

 Cayman Islands in 1891. 



There are reports of the occurrence of bud-rot in Santo 

 Domingo and Hayti, but their authenticity has not been 

 established. From Florida, the IJahamas, and Porto Hico the 

 disease appears to be so far ab.sent. 



As regards Central America, there are reports from 

 British and Spanish Honduras which .seem to indicate the 

 presence of the disease. Then- is no certain record of it 

 from Panama, and the coast fr'im Colon to Bocas del Toro 

 was examined by Johnston with negative results. 



In Trinidad the presence of bud-rot was contirmed 

 by Johnston in 1907, but compulsory destruction of diseased 

 trees, begun in 1909, has had the effect of reducing the 

 diseasf to insignificant proportions. 



In llie Lesser Antilles small outbreaks have occurred 

 iu (irenada, St. Vincent, and St. Lucia, which were met by 

 jirompt treatment, and no case has been reported from any 

 of the i.slands since 191.3. 



The disease is common in British Guiana and is reported" 

 from Surinam. 



SYMPTOMS. 



The following information is based on a recent circular 

 (in Spanish) of the Cuban Comision de Sanidad Vegetal, of 

 which Mr. J. R- Johnston is president, and a pamphlet oa 

 plant diseases by Mr. S. F. Ashby, Government Microbiologist, 

 issued by the Jamaica Agricultural Society. 



The account of the appearance of the disease given in 

 the Cuban circular is as follows: — 



The symptoms of bud-rot are the dropping of the young 

 nuts: the withering of the bud and eventually the leaves turn- 

 ing yellow: the lowest leaves first turn yellow and fall, followed 

 last by those .surrounding the bud. 



A new spike may grow out and then turn partially or 

 wholly black. The disease maj- begin in the centre of the 

 crown or lower down, either oa one side of the crown or at 

 the base of the leaf-stalk. 



Ashbj- differentiates between the symptoms according to 

 whether the disease starts outside the heart or within it. In 

 the first case the early indications consist of one or more of 

 the following: the dropping of 3'oung nuts followed by 

 blackening and withering of the stalks, one or more 

 leaves of middle age yellow and broken near the end, 

 many expanded leaves hanging down the trunk, bud 

 leaves yellow or withered, bud fallen over or fallen out. 

 These symptoms are not in themselves decisive, since they 

 may arise from causes other than bud-rot. Confirmatioi^ 

 is to be .sought in the shape of yellow sodden or dark sunken 

 spots and patches ai the base of the affected limb or fruiting 

 stalk, or a soft stinking rot of the young leaf-stalks within 

 the bud, or a similar rot in the top of the stem. 



When the disease starts within the heart there is 

 a wilted and drooping, or yellow and withered condition 

 of the youngest leaves, and the heart may have fallen over 

 or dropped out. These appearances also are to be confirmed 

 by the finding of a .soft rot on the young limbs, the leaf-stalks, 

 or the top of the stem. 



TKE.\TMEST. 



For the form in which the bud is not affected something 

 may be done in the way of cure by firing the dry leaves 

 hanging down, helped if necessary by the addition of a little 

 kerosene, and in addition, or alternatively, cutting out the 

 disea.sed tissue and treating the affected spots with a solution 

 of corrosive sublimate (1 in 50<i). 



In very early cases of the heart-rot, Ashby recommends 

 that a mixture ot oi|ual parts of powdered lime and powdered 

 copper sulphate bt- thrown into the heart, or that Bordeaux 

 mixture should be syringed into it. 



All advanced cases should be cut down, the crown cut to 

 pieces, the diseased portions thoroughly charred through, and 

 the rest well .scorched. 



W.NT. 



DESTRUCTION OF FOOD-PLANTS OF 



THE COTTON STAINER IN 



ST VINCENT 



The destructidii .(f{ 'John Hill, and silk-cotton trees 

 under the Ordinance .passed .some UKinths ago has been 

 vigorously pursued, and the Agricultural Superintendent, 

 Mr. M . N. Sands, li.i wards reports on what was achieved 

 duringthemontlis.il ( )ctober and November 1916. During 

 October, inStubbsi.. \illa district, 12-5 silk-:otton trees were 



