DISEASES OF PLANTS. 243' 



covered by the report The only suggestiou regarding treatment is the removal 

 of all infected plants and fruits from the field. 



Beport of the division of vegetable pathology, May-December, 1911, E. 

 AvEENA-SACci. {Bill. Agr. [Sao Paulo], IS. ser., 1912, No. 3, pp. 208-21,1, figs. 

 6). — This report includes besides other matters brief notices of plant diseases 

 observed, their characters, causes, and recommended protective measures. 

 Among these diseases may be mentioned anthracnose (CoUetotrichum gloeo- 

 isporiodcs), mummification {Botrytis citricola), rot (Pythiacystis citricola), 

 gummosis {Bacterium gunimis), and chlorosis of lemons; Botrytis anonw on 

 Anona ; bacteriosis {Bacterimn mori) and chlorosis of mulberry; mummifica- 

 tion {Gnoiiioniu p.sldii), and rust {Puccinia psidii) of guavft ; iicoleeotrichum 

 caricw and O'idiuiii caricw on Riciuus; Rhizoctonla violacea and Eryslphe coin- 

 iniinis on alfalfa; Perunospora vicice on vetch; Sclerotinia Uhertiaiia on legumes; 

 Tylenchus tritici, I'illetia Icevis, Ophiobolus herpoirichus, and 0. graminis on 

 wheat; Micrococcus tritici on wheat and rice; ChrysophUjatis endoMotica on 

 potato; and Plasmopara cul)ensis on cucurbits. A list of contributions on 

 plant diseases by the same author is appended. 



. Parasitic wilt diseases of cultivated plants due to fungi, H. W. Wollen- 

 WEBEK {Ber. Deut. Bot. Gesell., 31 {1913), No. 1, pp. ll-SJ,).— The author 

 reports that he has found these fungi as vascular parasites causing wilt dis- 

 eases of the following plants: Fusarium vasinfectiini on Gossypiion hertiaceum 

 and G. barbadense ; F. tracheiphilum (also causing a foot disease) on Vigna 

 sinensis; F. lycopersici (causing also a fruit spot) on Solanum lycopersicum; 

 F. niveum on CitruUus vulgaris; and VerticilUum alboatruin on 8. tuberosum. 

 S. mclongena, and Hibiscus esculentus. Sclerotium rolfsii is stated to cause 

 a foot disease on 8. melongena, also F. redolens n. sp. and F. sclerotium n. sp. 

 are claimed to cause foot disease on Pisum sativum and 8. lycopersicum, 

 respectively. Soil is said to be a predisposing factor in the production of 

 wilt, especially when the admixture of sand is considerable. It is thought 

 that bacteria also cause wilt diseases, but that most wilt diseases are due to 

 Fusarium in the warm regions and a smaller number to Vertici Ilium in colder 

 climates. 



On the causes which determine infertility of the soil and loss of crops, A. 

 Jachevski (KhozCaistvo, 7 {1912), No. S^. pp. 1103-1108; abs. in Internal. 

 Inst. Agr. [Rom^], Bui. Bur. Agr. Intel, and Plant Diseases, 3 {1912), No. 11, 

 pp. 2528-2531). — The author, stating that soil fatigue is frequently attributed 

 to wrong causes, cites cases observed where the effects were due to fungi, as 

 Fusarium lini, F. secalis, Helminthosporium gramineum, Cladosporium Jierh- 

 arum, Sclerotinia trifoliorum, and 8. libertia^ia. The last of these is said to 

 have adapted itself to different substrata, so that rotation gave unsatisfactory 

 results in many cases. The use of formalin or copper sulphate on the seeds, 

 burning of stubble, and disinfection of the ground with formalin, kerosene, or 

 carbon bisulphid is recommended. 



Infection studies with red fruited mistletoe (Viscuni cruciatuni), C. von 

 Tl^eeuf {Nalurw. Ztschr. Forst u. Landic, 11 {1913). No. 3. pp. 151-166, figs. 

 i2).— Continuing previous work (E. S. R., 20, p. 930; 22, p. 722) with infection 

 as related to the question of races, the author states that he has succeeded in 

 producing infection with greater or less subsequent development in case of 

 Olea europvea, Crataegus oxyacantha, Fraxinus cinerea, Syringa vulgaris, Prunus 

 padus, Pyrus malus, P. commums, Populus nigra, 8alix caprea, Cytisus laburnum, 

 Sorbus aiu-uparia, and Viscum album. It was found also that the pollen of 

 V. cruciatuni was capable of fertilizing the white species. 



Sterilization of seeds, Pinoy and Magrou {Bui. 8oc. Bot. France, 59 {1912), 

 No. 7, pp. 609-612). — The authors report that various leguminous and other 



