/I I ' [SSUI .1 .Mi U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF PLANT INDUSTRY— Circular N T o. 36. B. T. Q U.l.i iWAY, Chief of Bureau. THE BUD-ROT OF THE COCONUT PALM. JOHN R. JOHNSTON, Scientific Assistant, Laboratory op Plant Pathology. y.Ul.l ir.l WASHINGTON : GOVERNMENT PRINTING OFFICE : 1909 (Cir. 36] 2 BUREAU OP PLANT INDUSTRY. Chitf of Bureau, Beverly T. Galloway. Assistant Chitf of Bureau, Albert F.Woods. Editor, J. E. Rockwell. Chief Clerk, James E. Jones. B. P. I.— 487. THE BID-ROT OF Till- COCONUT PALM PREVALENCE OF BUD-ROT IN TROPICAL AMERICA. Notes in regard to the bud-rot of coconut palms have appeared in various publications in recent years, but it may not be generally known that apparently this same disease destroyed many coconut groves in the Provinces of Matanzas and Havana, Cuba, as early as 1886. A lone- report on the disease was published at Havana in L882. Its occurrence was reported in Baracoa, on the eastern end of the island, in L888, an 1 according to the natives it was present at least ten years before that time. In L834 a similar disease was reported from Cayman Islands and in L876 from British Guiana. To-day what apparently is one and the sai lisease, the bud-rot, occurs in nearly all the coconut-growing regions of Tropical America. COMPARISON OF BUD-ROT WITH VARIOUS COCONUT DISEASES. From time to time serious diseases of the coconut palm have been reported from different parts of the world and have been variously attributed to -oil or atmospheric conditions, to insects, fungi, etc.. and it is not at all improbable that various environments and organisms may bring about diseased conditions in the palm. It is quite certain, however, that in many cases these diseases, supposedly distinct, are all alike in that they exhibit a put rid condition of the crown, though this condition has been attributed to divers causes. It is now generally admitted that the rot of the crown in the district of Baracoa i- caused by bacteria. A published description of a disease said to lie of fungous one-iii in the Ila\ ana district corresponds exactl} to the Baracoa disease. On the island of Trinidad many of the trees said to be primarily dis- eased by a so-called root rot have all the symptoms of the bud rot. It cannot he stated positively that there is not a distinct root-rot or a fungous disease, bul the writer believes that the most destructive of the coconut troubles of Tropical America i- of the type found in Baracoa, Cuba. Personal examination of tree- iii Cuba, Jamaica. Trinidad, and British < iuiana has offered convincing evidence of this. The problem of idenl ifying the disease is of increasing interest from the fact that for some years a serious disease of coconut palm- has been reported from eastern countries. Of recent years these reports [CIr. ■ 4 THE BUD-ROT OF THE COCONUT PALM. have described the disease as similar to that occurring in Cuba. Many of the reports, however, have claimed that it is caused by fungi, and have made no comparison with the Cuban form. In Ceylon and in the Philippines the disease has been likened to the bud-rot. In India thousands of coconut trees have been lost, but, according to reports, owing to fungous attacks. The description of the disease, however, corresponds in every way to the bud-rot. De- scriptions of the destruction of palms in German East Africa and in Portuguese East Africa also coincide with reports of similar ravages of the bud-rot. DESIRABILITY OF A COMPARISON OF DISEASED MATERIAL FROM THE EASTERN AND WESTERN TROPICS. The Cuban bud-rot can not be easily mistaken. The falling of immature nuts and the browning of the central leaves and, finally, the putrid condition of the center of the crown are signs too conspicu- ous and easily determined to be overlooked. The fact that fungi or insects or an} r organism whatever are present does not alter the symptoms. Is it not likely that this virulent and widely destructive disease of coconut palms is common both to the eastern and western Tropics? It is much to be regretted that the investigators of the disease in the East have not been bacteriologists or at least have not for a time looked at the symptoms from that point of view. No comparison of photographs of material from the East and the West has as yet been made. It seems as though this were eminently desirable. A disease that has certainly been known for at least half a century and has steadily progressed, destroying grove after grove of thriving trees, not in one country only, but in many, demands more attention. It is greatly to be desired that there may be some comparison of material. It is still more important that the workers in different countries shall not only look at the disease from the viewpoint of the entomologist and mycologist but also from that of the bacteriologist. NECESSITY FOR FURTHER KNOWLEDGE OF THE DISEASE. As yet there is no satisfactory means of controlling this disease. Should the so-called bud-rot be found to occur in Africa, India, and the Philippines, as well as in Tropical America, it will then put the investigators on a more satisfactory basis for their work. If the disease is bacterial it may be that soil conditions or climatio changes are important factors in its spread in a virulent form. If these conditions be determined it may possibly be found that the only solution of the problem of identifying the disease is to obtain some variety either better adapted to local conditions or perhaps actually [Cir. 36.] Tni-: BUD-ROT OF THE COOONOT PALM. 5 resistant to bacterial attacks, li would be a long step toward this to ascertain definitely \\ hat countries are free from and what counl ries arc a til ict I'd with :i rot of the crown of the palm, whatever may be thought to he the cause. It' the investigators at the different -tat ion- will bear this in mind it will aid in solving the problem of controlling one of the mosl baffling and destructive of tropical plant diseases. The writer has in preparation a full account of his investigations of the disease throughout the West Indie and w ill be glad to recei\ e for comparison photographs <>r alcoholic material. Approved: d VMES WlLSON, .v, cri tary of Agricultun . Washington, D. C, Jum 9, 1909. [Clr. 36] O Digitized by the Internet Archive in 2013 http://archive.org/details/coconutpOOunit UNIVERSITY OF FLORIDA 3 1262 08928 9606