484 FUNGI IMPERFECTI. 



Gl. ampelophagum (Pass.) 1 Black-rot of the vine. This 

 disease is very injurious and has a wide distribution in Europe. 

 It is known under many names such as " Pock, Brand, Host, 

 Jausch, Brussone, and Nebbia nera," though probably these 

 names include several distinct diseases. The identity of this 

 Gfloeosporium is somewhat uncertain, and it may really be 

 identical with Phoma tn///>i/i,i,/nii (p. 467). IJathay ascribes the 

 black rot to Sphaceloma (Phoma) ampdinum, while Thiimen 

 regards Grloeosporium as the cause. Briosi arid Cavara consider 

 the two species of fungi as distinct. Thiimen says that the 

 patches of Gloimporiu.m are for a considerable time disc-like 

 and of a light-grey rose colour ; those of Phoma, on the other 

 hand, are always depressed and brown. Eathay, however, de- 

 scribes the spots of Phoma as at first dark brown, and later 

 ashy grey with a brown margin. 



The spots appear on green parts of the vines during April 

 and May. Those on the leaves frequently fall out, leaving 

 holes. On the grapes the spots are smaller and produce a 

 brown coloration extending deep into the fruit. The conidia 

 are small, hyaline, oval, and unicellular ; they are abjointed 

 from very short conidiophores arranged in little clusters. The 

 conidial patches rupture the host-epidermis, and the conidia are 

 liberated. 



Thiimen suggests that the soil of vineyards should be kept 

 well cleaned, and that the stake mode of culture be used in pre- 

 ference to an overhead trellis ; he also recommends the washing 

 of all parts of suspected vines during winter with 10 to 15 

 per cent, solution of sulphate of iron. This treatment is said 

 to have been very beneficial in keeping many vineyards quite 

 healthy and free from fungi. 



*t o 



Gl. nervisequium.' 2 This parasite occurs on species of Plata HH* 

 in P^urope and America. Brown spots appear on the leaves, 

 especially on the veins ; these as they extend cause sudden 

 withering and fall of the leaves. Pustules containing a stroma 

 develop on the spots, and unicellular, ovoid, hyaline conidia are 

 abjointed from club-shaped conidiophores. 



1 Thiimen, Die Pocken an Wein u. OW. 1885; Die Bekampfung d. Pihkrank- 

 ln'iti -it, 1SS6; De Bary, Annalen d. Oenofogie, iv. ; Viala, Lex maladies de la Vii/n' ; 

 Briosi e Cavara, Funglii paranit., in. ; E. Eathay, " Der Black-Rot" 1891. 



- U.S. Ann >!<" l>i /in,-tin< n< <>f Vegetable Patholof/y, Report for 1888, gives a 

 general account of this disease. 



