74 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fungi. 



(By A. LoBBAiN Smith, F.L.S.) 



Culture Medium for Zygospores.* — J. J. Hamaker claims to have 

 discovered a culture medium on which, with proper conditions of mois- 

 ture and temperature, a successful groA^iili of the zygospores of 3f7icor 

 stolonifer can be induced. 



New Ascomycetes.t — W. Kirchstein describes fifty-three new species 

 from the Mark Brandenburg. There are several new genera recorded : 

 Hyphodiscus near to Tapesia and to Trichobelonium but with globose 

 spores ; Ophiospfueria with elongate one-celled spores near to Niesslia ; 

 Pachyspora belonging to the Trichosphariacete, the asci two-spored, the 

 spores two-celled, dark brown. BertieUa a genus of Melanonimese with 

 a polysporous ascus and two-celled colourless spores, must be called 

 Kirchxteinia as the name BertieUa has already been used ; the fungus 

 recalls the appearance of Bertia. Finally, hedescrilies 7Vematosph(Brella, 

 distinguished from 7Ve)natosph(eria by the perithecium and the absence 

 of paraphyses. 



Study of the Grey Rot of the Vine.|^Gy. de Istvanffi has made 

 an exhaustive study of this disease, found to l)e due to Jiotrytis cinerea 

 {Sderotiiiia Fvckeliana). The first part of the work is taken up with 

 microbiological studies : the germination of the spores and their beha- 

 viour in various culture solutions, their resistance to drying and to cold, 

 etc. The author also tested the spores and their capacity to germinate 

 after soaking them in Bordeaux mixture, in glycerin, and organic salts. 

 The results of all these experimental researches are given. The sclero- 

 tium is also studied and the development of the clamp organs — Haft- 

 organen. He describes two types of these : the first are hollow bodies 

 and die off ; the second develop further and form zones of hyphal tissue 

 of darker and lighter colour. The sclerotia are formed from these larger 

 clamp organs. They take several months to ripen, and germinate under 

 suitable conditions with conidiophores of Botrytis. 



Diseases of Plants due to Sclerotinia. — Emil Molz§ writes on the 

 conditions affecting the appearance of Sclerotinia frndigena on apples. 

 The conditions, studied by him and tested by a long series of experi- 

 ments, which are presented in tabular form, had reference chiefly to 

 light, temperature, and moisture. He found generally that darkness 

 and a low temperature hindered the gi'owth of the fungus. In the case 

 of stored fruit a slight current of air would scatter the spores from a 

 diseased apple and infect a large number of sound fruits. A careful 

 watch would remedy this, as the apples attacked show rottenness very 

 soon and should be removed at once. Too great moisture was also 

 proved to be a powerful agent in encouraging the growth of Sclerotinia. 



* Science, II. xxiii. (1906) p. 710. See also Bot. Centialbl., cii. (1906) p. 583. 



t Abh. Bot. Ver. Prov. Brandenburg, xlviii. (1906) pp. 39-61 (5 rigs). See also 

 Ann. Mycol.,v. (1906) p. 455. 



X Ann. Inst. Centr. Amp^lol. R. Hongrois, iii. (1905) p. 183 (8 pis. and 15 figs.). 

 See also Centralbl. Bakt., xvii. (1906) pp 280-9. 



§ Centralbl. Bakt., xvi. (1906) pp. 175-8 (4 figs.). 



