442 EXPERIMENT STATION BECOED. 



DISEASES OF PLANTS. 



International phytopathologic collaboration, J. Ebiksson {Phytopathology, 

 5 {1915), No. 3, pp. 133-138). — The author reviews the steps that have been 

 taken in Evu'ope to secure a systematic collaboration for the control of plant 

 diseases, and expresses the hope that this country will take the initiative and 

 assume charge of an organized international collaboration against diseases of 

 cultivated plants. It is maintained that the means adopted in Europe have not 

 advanced phytopathological research, w hich is considered fundamental to proper 

 regulatory control. 



Some neglected phases of phytopathology, J. G. Grossenbacheb {.Phyto- 

 pathology, 5 {1015), No. S, pp. 155-162). — The author describes some types of 

 phloem and bark diseases of herbs and woody plants in order to call attention 

 to .some of the problems in phytopathology which, he considers, should rcveive 

 more general attention, not only because they are of scientific interest but 

 also because they arc important frfmi an economic standpoint. 



[Plant diseases in British Guiana], C. K. BANCROtT {Rpt. Dept. Sci. and 

 Agr. Brit. Guiana, l'J13-14, A pp. 2, pp. 18-20). — In a report on the work of the 

 botanic gardens at Geoi'getown, an account is given of plant diseases investi- 

 gated during 1913-14. 



It is stated that the dry disease of sugar cane due to Marastnius sacchari has 

 shown a marked increase on some plantations since its first appearance in 

 Berbice in 1907, and that it has become widely distributed in the colony. 



A leaf disease of the sisal hemp noted on one estate was found to be due to 

 CoUctotrichum agaves. 



Investigation has been begun on bud rot of coconut palm, from which six pure 

 strains of bacilli of the Bacillus coli type have been isolated. Inoculation with 

 one of these has resulted in the death of the plant. 



A disease prevalent on the fruits of peppers was found to be due to C. 

 nigrum. Hose leaf mildew {Spha-rothcca pannosa) responded rea<lily to' treat- 

 ment with flowers of sulphur, but less favorable results followed the use of liver 

 of sulphur or of dilute sulphuric acid. 



A leaf spot of orchids was ascribed to Uredo orchidis. A leaf disease of 

 nursery plants of Ilevea was found to be due to a fungus considered by Massee 

 to be a new species and named J'assalora hcvco'. Specimens of rose trees were 

 received which showed the development of crown gall {B. tumcfacicns). A leaf 

 disease of coconut palm caused by Pestalozzia pahnaruin was observed in 

 sevefal places. 



Foines scniitosttts was found on a single dead stump in the foi-est, this being 

 supposedly its first record in the tropical regions of America. 



Brown root disease of Hevea, due to Hymcnochfetc noxia, was noted in one 

 or two instances. Eutypa caulivora was identified on Hevea material brought 

 from Ceylon. Several cases of the mango fruit disease {Gloeosporium tnangi- 

 fcrw) were noted in the botanic gardens. 



Angular leaf spot of cucumbers. E. F. Smith and Mary K. Buvan {U. S. 

 Dept. Agr., Jour. Agr. Research, 5 {1915), No. 11, pp. 465-476, pis. 7).— A de- 

 scription is given of an angular leaf spot of cucumbers which, it is said, has 

 been known to occur in this country for many years, being widespread In the 

 Eastern and Middle Western States. 



The disease is characterized by angular brown spots which tear or drop out 

 when dry, giving the leaves a ragged appearance. In the early stages a bac- 

 terial exudate collects in drops on the lower surface during the night and dries 

 whitish. Young stems and petioles may become soft rotted or cracked open. 



