504 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Fungi found in Butter.* — Weigmann and A. Wolff have examined 

 butter that tasted of turnips, and have isolated several fungi, notably 

 Penicillium brevicaule. The other forms were less easily determined, 

 but one or other was akin to Monilia, Mycoderma, Oidium, etc. The 

 authors of the paper made many cultures on various substrata, testing 

 the habits of growth and also isolating the substances formed by these 

 fungi. 



Changes Effected by Filamentous Fungi on the Media in which 

 they are Grown.f — It has been generally remarked that considerable 

 changes are effected in culture media during and by the growth of 

 bacteria, fungi, etc. The changes so produced may be favourable or 

 unfavourable to further growth of the organisms, and also the sub- 

 stances thus formed can be destroyed by heat. Otto Lutz has examined 

 these hypothetic products in reference to their influence on germination 

 and on the further development of the fungi. He explains his methods 

 of work, and gives a list of the fungi selected for experiment. He 

 found that Mucor Mucedo and Rhizopus nigricans were the most service- 

 able, as they were extremely sensitive to change. A long series of 

 experiments is given, with detailed results in each case, and in the final 

 summing up the author states that in the most varied substrata sub- 

 stances are formed which hinder further growth of the fungi. It has 

 been impossible to determine the chemical nature of these substances, 

 or to decide if one or more were concerned as deterrents. They 

 resemble enzymatic bodies in being sensitive to high temperatures, 

 which destroy or lessen their activity. They are also rendered inactive 

 by high dilution, and are destroyed by light, especially the violet rays. 

 In cultures carried out in the light, substances were formed that 

 encouraged growth ; these were also destroyed by high temperatures. 



Plant Diseases. J — A disease attacking gooseberry bushes called the 

 collar-fungus, due to Cytosporina Ribis, has been reported to the Board 

 of Agriculture from Huntingdonshire, Cambridge, Hereford, and Kent. 

 The fungus was first detected in Holland by Van Hall. The bushes 

 are attacked immediately above the ground, where the bark is killed. 

 The fungus is imbedded in the bark as small black bodies. Sometimes 

 the larger roots are attacked. In other cases a branch is attacked, and 

 the fungus spreads until the tree is killed. It is evidently a wound 

 fungus, as it occurs somewhat irregularly among the bushes, though a 

 grower in Kent stated that bushes planted in a certain circumscribed 

 area in his garden were always killed, while those near by remained 

 healthy. 



Attention is also directed § to the serious nature of the gooseberry 

 mildew. Instruction is given by the Board of Agriculture as to the 

 recognition of the disease ; the precautions to be observed by gooseberry 

 growers ; and as to the treatment of infected bushes. Disease may appear 

 any time between May and November, and growers should keep liver 

 of sulphur at hand for spraying purposes. Affected berries or shoots 

 should be destroyed as soon as noticed. 



* Centralbl. Bakt., xxii. (1909) pp. 657-71 (6 pis.). 



t Ann. Mycol., vii. (1909) pp. 91-133. 



j Journ. Board Agric, xxi. (1909) pp. 34-5. § Tom. cit., pp. 117-25. 



