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The Conference lasted from 28th January to 1st February, and I attended most of its meetings. On the 29th I gave a short paper on the work of the Bureau following one by Dr. Neave on the Bureau of Entomology. Professor Ashby spoke highly of the value of the Review and the work the Bureau is doing. A number of the papers had a mycological bearing and were of special interest to me, but as a report of the Conference is being published separately it is unnecessary to say much about them here. On Thursday morning, 31st January, I visited the Hope Gardens with Mr. Hansford and Professor Ashby and saw the work in progress there with sugar-cane, and various interesting diseases, particularly a Phytophthora rot of pineapples and mildew of mangoes. On 1st February an excursion had been arranged for the Delegates to visit the citrus plantation of the United Fruit Company, and a sugar and banana plantation. The citrus plantation, largely grape fruit, was well worth a visit as entomogenous fungi abounded. Beautiful specimens of citrus scab on nursery stock were also seen. The banana plantation was noteworthy as the plants were grown under irrigation and had not been attacked with Panama disease. During my stay in Jamaica I was requested to call on the Colonial Secretary, who expressed his high appreciation of the work of the Bureau, but wished to obtain all possible arguments to support the grant to the Bureau in the Legislature and also to discuss future, financial requirements.
At Barbados, on my way out, I met Mr. Bovell, Director of Agriculture, and his assistant, Mr. Skeat. We visited the Department of Agriculture and then toured through a good part of the Island, where an extensive sugar cultivation is carried on.
Mosaic disease of sugar-cane and of maize was demonstrated, and Mr. Bovell also showed us his method of raising seedlings of sugar-cane, many of his new varieties having been of utmost service to the cane-growing communities of the West Indies.
During my stay in Trinidad, where I spent altogether fifteen days, I visited the St. Clair Experiment Station a number of times, meeting Mr. Freeman, the Director of Agriculture, Mr. Nowell, Assistant Director, Mr. Stell, Mycologist, and various other members of the staff of the Agricultural Department. In the grounds of the Station, especially interesting were the varieties of lime reputed to be resistant to withertip but of which one was badly attacked, the cacao and coffee seedlings, oil palms, dwarf coconuts, and various diseases, particularly Melanop- sammopsis ulei which destroys the Hevea rubber in Guiana, but which in Trinidad appears only to attack the young trees, Cephaleuros mycoidea on rubber, and Cercospora spot on yams. I had many opportunities for discussing the question of withertip with Mr. Stell and Mr. Nowell, and also later with Professor Ashby. I visited the Government Farm, which is under the charge of Mr. Nowell, and a particularly virulent disease of coconuts was first demonstrated to me, the etiology of which is obscure but which is being investigated by the Department. The symptoms are the discoloration of the young inflorescences whilst enclosed in the sheath, the wilting and bending over of the youngest leaf, which can often be pulled out owing to the rotting of its base, and finally the death of the tree.
The farm includes a number of experimental plots under various crops, particularly varieties and manurial trials of sugar-cane. In the latter the effect of manurial treatment on the incidence of Leptosphoria sacchari was most marked. Banana plots included one of Gros Michel planted on land which, ten years previously, had carried a crop affected with Panama disease. A number of plants of the present crop had already been found infected, so that it appears that the causal fungus can remain in the ground for at least ten years. Plots of sea island cotton (with Ramularia), pineapples, cocoa, and sweet potato were also seen, and young seedlings of sugar-cane. A two-day trip across the Island to the Mayaro Beach and Guayguayare on the south-eastern coast was arranged for Dr. Neave and myself, and we were accompanied by Mr. Urich (Entomologist) and Mr. Schelt (cocoa expert). We passed through much of the cacao area on our way, and I had an opportunity of seeing Phytophthora faberi both on the stem and fruits, and also cases of root rot. At Mayaro we visited one of the largest cocoa estates on the Island, the manager taking us round a large part of the property. On the Mayaro coast a belt of coco-nuts, some of the best in the Island, stretched for upwards of fifteen miles. The bad influence of clay soil showed up very clearly in one spot, but, apart from a few cases of canker and doubtful red ring, disease appeared to be
absent.
I spent two days with Professor Ashby at the Imperial College of Tropical Agriculture. He showed me some sea island cotton plants artificially infected
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with Angular Leaf Spot (Bacterium malvacearum) which is responsible for the present serious outbreak of the "black arm" form of this disease in the Sudan. Professor Ashby has obtained from Grenada a type of banana called "Giant Fig." This banana fulfils the requirements of the exporting fruit companies, that is to say,
it packs well, has long-fingers, and need not be crated. It was thought to be resistant to Panama disease, and so far, under very rigorous tests applied to it, has proved quite resistant, while Gros Michel under similar conditions has been almost completely destroyed. Later, at the Conference, it appeared that this variety of bapana is known in Jamaica, where it is called the robusta variety, and, whilst acknowledged to be resistant, is said to have a weak stem, a point of some import- ance in a hurricane zone. Whilst at the College I also met Professor Harland and saw some of the work on the raising of seedling bananas and sugar-cane in progress. Mr. Stell took me by car to visit a coconut plantation a little north of Port of Spain. Here the disease of coconuts seen at Government Farm was causing havoc. Large numbers of trees were in process of decay and many gaps already showed where the earlier victims had been. The ground was trenched and the trees on one piece of land appeared to be attacked whilst those on adjacent land separated by a trench often did not show the disease. The building of a low sea wall which prevents efficient drainage may have had something to do with the present condition of the trees, particularly as up to the present no causal organism has been isolated.
On another day we went to see two lime estates situated at Carenage near Port of Spain. Both were attacked by withertip, and one was abandoned on account of this disease. Last year these trees bore a crop of fruit, although for some years previously no crop at all was obtained. Unhappily, I was ill five days of my stay in Trinidad, which curtailed some of my expeditions.
The visit to San José was of great value, as the route from Port Limon traversed a large tract of country where Panama disease has been doing its worst. The original banana lands near the coast and those for some miles inland are now given over to cacao. As the disease progressed, new plantations have been continually opened up further inland until now the newest plantations are within some few miles of San José itself. The elevation in this region is so great that the climate is not favourable to banana growing. All stages in the destruction of the plantations by the disease could be seen from the carriage window, and the contrast with the perfectly healthy plantations in Jamaica, visited later, was most striking. Around San José coffee is largely grown and I saw a large acreage under this crop. On returning from Jamaica a call was made at Colon, and Professor Ashby, who travelled by the same boat, arranged for us to meet Dr. Zetek of the Bureau of Plant Industry, Washington, who is in charge of the agricultural work of the I also met Dr. Snyder, of the United States, an authority on ter- mites, who is forwarding us specimens of termites attacked by an entomogenous fungus.
Panama zone.
On my way to Dominica, the boat stopped a day at St. Lucia, and Mr. Stell, who travelled with me from Trinidad, arranged for us to see a large banana under- taking which is just starting and which has already some trouble with Panama disease. We arrived at Roseau, the capital of Dominica, on the morning of the 15th February and immediately called on the Administrator and later on Mr. Jones, the Curator of the Botanic Gardens, who arranged a programme for my stay. Mr. Stell and I went to Watten Waven, an estate some few miles towards the interior, on the same afternoon. The next day we visited Geneva, riding through large tracts of roughly cultivated hillside plantations of limes. Geneva estate is situated on the south-western coast and includes a level sea coast area which is, however, covered with boulders. We returned to Roseau the same evening and on the following morning left for a tour round the north and windward coast where many of the most important estates are situated. We reached Portsmouth on the same day and proceeded to the Picard estate. Here and in many other places the trees had been interplanted with Glyricidia as a nitrogen collector--a sound practice in pre-withertip days but one which now probably helps to reduce the ventilation of the plantations which is so important for the early dispersal of dews. Leaving Picard we visited in turn the estates of Blenheim, Hampstead, Woodford Hill. Eden, Londonderry, Melville Hall, and Governor, finally returning to Roseau after an absence of five days. The following day (the 22nd) we went up the Layou Valley. the largest and best situated valley in the Island, to see the Clarke Hall and Hillsboro' estates. On the 23rd, an expedition to the Imperial Road falling