il: 



THE AGRICULTURAL NEWS. 



December 19, 1914. 



FUNGUS NOTES. 



SUMMARY OF INFORMATION CONCERN- 

 ING PLANT DISEASES GIVEN IN 1914. 



In accordance with past custom, there is given below 

 a resume of the articles and reviews which have appeared 

 under the heading of Fungus Notes during the year. 



SUGAR-CANE. Two papers giving the results of recent 

 work on sugar-cane diseases in India are reviewed on page 62. 

 The authors regard red rot, due to CoUetoti'ichum falcatum, 

 •AS the most serious of these diseases, and discuss tlie methods 

 i.f infection, and the possibility of reducing the prevalence of 

 tlie disease by means of sett selection. Three new diseases: 

 a wilt, a collar rot, and a leaf spot, are announced and 

 described. 



CITRUS TREES. On page 238 a description is given of 

 a new fungus, of the genus Atichia, occurring on lime leaves 

 in Dominica. It is of no economic importance. The 

 Rosellmia root disease of lime trees is the subject of an 

 article on pages 36-l:-.5, written as an outcome of a recent visit 

 to Dominica by the Mycologist of this Department, made in 

 order to investigate the extent and condition of its occurrence 

 in that i.sland. The nature of the disease and the measures 

 to be adopted for its prevention are discussed at some length. 



CACAO. The Rosellinia root disea.se of cacao, prevalent 

 in St. Lucia, is dealt with in the Mycologist's report on a visit 

 made to the affected districts in the early part of the year, 

 given on pages 94-5. The Dominica article mentioned above 

 should be read in connexion with this report The species 

 occurring in St. Lucia is not the same as the one generally 

 found on limes in Dominica, but the diseases they produce 

 are essentially alike in their characters. 



COTTON. An article dealing with a physiological affec- 

 tion, known as leaf-cut, which occurs in the United States, is 

 reproduced in full on pages 1 26-7. It is of interest in the West 

 Indies because of the occurrence of a disea.se with similar 

 symptoms in St. Croix, St. Kitts, and Nevis. An article on 

 the subject of the latter disease will appear in an early 

 number of the West Inddan Bulletin. 



An interesting suggestion with regard to the treatment of 

 cotton seed with hot water for the purpose of freeing it from 

 anthracnose infection is reproduced on page 396. The 

 methbd has not yet been fully worked out or tested, but 

 should it prove successful it will he worth the serious atten- 

 tion of cotton growers in those islands, such as St. Vincent, 

 where the moist climate favours the development of this 

 disease. 



coco-NUTs. Further information concerning bud-rot in 

 India, summarized on page 286, confirms the view already- 

 current that the disease in India is quite different in its 

 nature from that knowp by the same popular name in the 

 West Indies, the former being due to the fungus Pt/thium 

 palmivormn, which is not known to exist in the New World. 

 In connexion with this fungus a note is given on page 222 

 effectively discrediting an alleged record of its occurrence 

 1)1 Mexico. 



MISCELLANEOUS PLANT DISEASES. 



Pine-apples: During a visit to St. Kitts the Mycologist 

 found a disease oi'' arring in the Experiment Station, which 

 agrees in all respects with the base-rot of pine-apple plants, 

 due to I'hielai'iopsis pan doo:n, first described from Hawaii. 

 I ; attacks the underground p' rtion of the stems of cuttings 

 < / young plants, and ■ oduces a sickly yellowish ajspearance 



of the leaves. It is liiijely to be difficult to deal with in 

 a sugar-cane country, since that crop supplies an abundance 

 of infective material. Information as to the disease is given 

 on page 190, and particulars as to the fruit rot of pine-apples 

 due to the same fungus, will be found on page 222. 



Tomatoes: On pagel74 two tomato diseases, the blossom- 

 end rot of the fruit, and the Cladosporium disease of the 

 leaves are recorded as occurring in Barljados. A descriptioa 

 is given and remedial measures suggested. 



Sweet Potatoes: The sweet potato appears to be singularly 

 free from diseases in the West Indies, considering the 

 long list of fungus troubles in the United States. In order 

 to facilitate recognition should they be met with, a sunmiary 

 of the known diseases is given on page 110. 



Ground Nuts: Some encouraging results obtained in 

 Montserrat from the spraying of ground nuts for the control 

 of leaf rust are reported on page 380. 



Imniorlel: A note on the canker which threatens to 

 kill out this useful cacijp shade tree in St. Lucia is included 

 in the report of the Mycologist's visit on page 94. Cultures of 

 a bacterium suspected to be the cause of the disease have 

 since been obtained, but the investigation has been suspended 

 owing to pressure of other work. 



Imphce: In connexion with the occurrence of sorghum 

 smut in ^Montserrat, the simple and effective methods available 

 for the destruction of its .spores on the seed are described oa 

 page 316. 



Letiuminous Plants: An article on Fusarium wilt of 

 legumes, and the occurrence of Neocosmospora vasinfecta on 

 Tephrosia Candida in Montserrat appears on page 348. 



Effi'ct of Grass on the Groivth oj Trees: Though not 

 strictly .speaking a plant disease, the possible toxic effects 

 of grass growing above the roots of trees appear well worth 

 attention in the light of the Woburn experiments, and 

 a summary of the results obtained from these will be found 

 on page 302. 



Damping of of Seedlings: Two useful notes concerning 

 the prevention of this familiar trouble appear on pages 1.58 

 and 380. 



FUNGICIDES. A method of making Bordeaux mixture, 

 more adhesive by the addition of casein is noted on page 46. 

 More recently the use of milk for this purpose has been 

 suggested. An important article on the purchase and use of 

 liver of sulphur, dealing with the great variation found iui 

 commercial samples of this substance, and its tendency to- 

 rapid deterioration unless properly stored, is reproduced on 

 pages 254-5. 



Several notes on the subject of soil sterilization have 

 appeared during the year. The methods of working, and the 

 plant required when soiUs moved into boxes for sterilization 

 with steam or formalin, are given on pages 78-9; jnethods- 

 of sterilising .soils in situ are outlined on pages 95, 158, and 

 380: while a method involving the use of carbon bisulphide in 

 emulsion is described on pages 202-3. The last named is now 

 being tested on a considerable scale in Dominica. 



Instructions for the generation of formaldehyde gas for 

 the fumigation of fruit, etc. are given on page 222 in connex- 

 tion with the storage of ^ pine-apples. 



ENTOMOGENOUS FUNGI. A note on the effective control 

 of scale insects in St. Lucia by fungi apjjeared on page 94, 

 and articles on the use of the green muscardine fungus in. 

 Samoa for the control of the rhinoceros beetle, a pest of 

 coco-nuts, were reviewed on page 78 and under Insect 

 Notes on page 10. The same fungus has been in use for 

 some years in Trinidad against the froghopper, and has been 

 found on larvae of the sugar-cane root borer in Barbados. 



