414 



THE AORICULTURAL NEWS. 



December 23, 1911. 



FUNGUS NOTES. 



SUMMARY OF INFORMATION GIVEN 

 DURING THE YEAR. 



In the following article is summarized the information 

 relating to diseases of crops, and to other matters of interest 

 from the plant-pathological point of view, that have appeared 

 in the volume of the A'jricultural Kews concluded by this 

 number. The object of the articles that have appeared under 

 this heading has been to present to those interested a review 

 of the work on diseases of crops that is in progress, not only 

 in the West Indies, but in all parts of the world, as far as it 

 is in any way relevant to conditions obtaining in these islands. 

 It follows that many of the articles lay claim to no original 

 research on the part of this Department, Imt there are some 

 exceptions. The information relating to the ' burning' disease 

 of arrowroot in St. Vincent, p. 174, and that presenting some 

 facts connected with root diseases of cacao, C'astilloa, limes 

 and some other plants, given on pp 222 and .366, is the out- 

 come of work conducted by the Mycologist to this Depart- 

 ment; furthermore, the articles on miscellaneous fungi, 

 appearing on pp. 190 and 222, have resulted from the exam- 

 ination, in the laboratory at the Head Office, of specimens 

 forwarded from the different i.slands by the local officers and 

 by others interested in the subject of plant diseases. 



RUBBER ANii cAC.\o TREES. It is now generally accepted 

 that two itMportant diseases of Para rubber and cacao, namely 

 canker and die-back, are of the same origin on either host 

 plant. Some account of Fetch's work in Ceylon, which led 

 to this conclusion, will be found on p. 7S, where it is shown 

 that I'lii/lnplithiiva Fahcri is the cause of canker on both hosts, 

 a.s well as of a rot of the fruits of Hevea, very similar to that 

 of cacao pods, due to it. ^Mention is made on the same page 

 of Bancroft's preliminary work on the die-back fungus of 

 Hevea and cacao, and of his discovery of its perfect or asci- 

 gerous stage. In consequence of this, its name is changed to 

 Thpridaria tarda, and thus an end has been put to the com- 

 plicated mass of synonyms, such as DijAocUa caraoicala, 

 Lasiiidiplodia thenliromae, as well as many others, by which 

 it was formerly known. An account of Bancroft's further 

 work, and of his succe.ssful inoculation experiments on Hevea 

 with spores of the fungus produced on cacao, is given on 

 p. 2K6. The occurrence of the black root disease of the West 

 Indies on caca<i and Castilloa is mentioned on j)p. 7S and 

 222; a further description of this appears on p. 306, as is 

 stated below. 



SUGAR CAM'.. A short account of the disease of sugar- 

 cane known in Java as Sereh is given on p. 23t<, where 

 attention is aIsu called to the ease with which it may be 

 confused with other diseases of this plant. 



PALMS. Bud rot of certain palms in India, as described 

 by Butler, received attention in two articles appearing on 

 pp. 14 and 30, respectively. The three palms concerned 

 are the Palmyra (Borassvs Aabellifer), the cocoa-nut and the 

 areca nut (Areca Catechu). Of these, the Palniyrii, by far 

 the most important economically, is that upon which the 

 most serious damage is inflicted. The organi.'-ni responsible 

 for this is a species of Pythium tailed by llutler /'. pahiii- 

 vorwn — one of the more primitive fungi. The methods of 



infection are discussed, and an outline is given of the cam- 

 paign undertaken for combating the disease. On p. 206 

 appears an account of Coleman's work on a rot of the nuts 

 and terminal bud, of the Areca palm, as it occurs in Mysore. 

 In this case the causative organism is a variety of Phytoph- 

 thora omniriiTa, called by Coleman, var. Arecae, and is very 

 closely related to F. Faha-i — the fungus causing cacac 

 canker and pod disease. 



ciTEU.s. On p. 46, a resume is given of the work con- 

 ducted by Fawcett on two diseases, namely, scaly bark and 

 scab, in Florida. The first is due to a species of Hormode- 

 dron — a form often included in the life cycle of Clados- 

 porium. It is not as serious in its eflFects when it oecurs 

 alone, as when it is followed by the citrus wither-tip fungu.s, 

 CoUetotrichura gloeosporioides: its attacks are principally 

 confined to the orange. The second, due to Cl'idospm-inm 

 citri, rarely if^ ever attacks this tree, but is found on several 

 other species of Citrus. Two fungi on limes in Dominica, 

 namely Fomes lucidus and Po/i/slictus hir-iuttts, are referred to 

 on p. 190; and on p. 270 the suggestion is made that the 

 former may be responsible for a form of root disease of this 

 plant found in Montserrat and Antigua. The attack of 

 black root disease on the orange in St. I .ucia is mentioned 

 on p. 222; and its occurrence as well as that of red root 

 disease on limes in Dominica is recorded on p 366 A third 

 form of disease — stem canker — on the same host in that 

 island, is dealt with on page 382. Finally, a disease of Natal 

 citrus fruits, described by Pole Evans and attributed by him 

 to Diplodia imtalensis, receives attention on p. 318, where 

 mention is made of a gum-inducing fungus closely related to 

 the above, which attacks the peach and Citrus, in Florida. 



BANANAS. Some diseases of bananas, found in Central 

 America, Surinam and Trinidad, are reviewed on p. 1 10. They 

 comprise the Panama disease, attributed by Essed to Ustila- 

 qinoideHa niiisaeperda, in Surinam; the moko disease of 

 Trinidad due, according to Borer, to bacteria; the root disease 

 due to .]farasmius semiiistus, found in Trinidad and else- 

 where; and the disease known in Surinam as elephantiasis. 

 Further information on the Panama and moko diseases is 

 given on p. 254. 



PlNE-.\PPLEs. Some account of one of the chief para- 

 site of this host, namely TkiflniHopsis paraduxa, a fungus 

 also causing pine-apple disease of cane cuttings and stem 

 bleeding of cocoa-nut palms, is given on p. 126. The two 

 succeeding articles on pp. 142 and 1.56 are devoted to an 

 account of Larsen's work on pineapple diseases in Hawaii. 

 These are: fruit rot, base rot of cuttings and leaf spot — all 

 due to Thielam opsin piirado.ra; brown rot — possibly the same 

 as black he.irt — of uncertain cause: ripe rot, wilt and tangle 

 root, the cause of which is also not finally determine, 1. 



ARKOVVROoT DISEASE. On p. 174 appears a preliminary 

 note on a discaJ'fe of arrowroot, long known in St. Vincent as 

 burning. The attack of the causative fungus on other host 

 plants is noted, and remedial measures are suggested. 



itooT DISEASES. Information of a preliminary character 

 on the root d'iseases attacking limc-i, cacao, pois doux and 

 .some other host plants is to be found on pp. 366 and 382. 

 Three definite diseases are distinguished. The first is due to 

 a species of Ivosellinia; it has been given the popular name of 

 black root disease. It attacks several plants and is, in all 

 probability, to be found in Dominica, St. Lucia, St. Vincent 

 and Grenada. .\ note on the same disease may be found on 

 p. 222. The second, due to Spliaerostilhe sp., occurs on 

 limes in Dominica, and will probably be found elsewhere; it 

 has been called red root disease. A third form of disease 

 attacking the collar and roots of limes, in Dominica, has been 



