144 
Pilzkrankheiten der Pflanzen 
Endothia parasitica. Pycnospore cultures were compared with similar 
cultures of American material and proved to be identical. In July 14 
inoculations were made on sprounts of Castanea dentata, using the Chinese 
fungus, and in one week the disease began to show. At the end of two 
weeks all inoculations had taken effect and produced areas of sunken bark 
often extending 2 to 3 cm from the line of inoculation. In about 5 weeks 
one canker had reached 6x14 cm. Pycnidia and pycnospores were pro¬ 
duced, the latter averaging 4,75x2,05 g, practically the same as from 
American material. 
Later, tpyical cankers bearing perithecia were received from China. 
The perithecia and ascospores proved to be almost identical with E. 
parasitica from America. Humphrey (Madison, Wise.). 
FAIRCHILD, DAVID, The discovery of the Chestnut bark disease 
in China (Science, N. S., 1913, 38 [29 Aug.J, 297—299). 
The American Chestnut blight fungus, whose origin has hith¬ 
erto been in doubt, was found in June by an explorer of the United 
States Department of Agriculture on native Chestnut north of Peking, 
Chin a. The native Chinese trees were quite resistant to the disease, no 
dead ones being seen. The organism was checked up fully with Endothia 
parasitica (Murr.) by Shear and Stevens and found to be identical. 
Humphrey (Madison, Wise.). 
ANONYMUS (SORAUER), Die neueren Untersuchungen von Quanjer 
über die Ursache der Blattrollkrankheit und der SoRAUERsche 
Standpunkt (Zeitschr. Pflanzenkrankh. 1913, 23, 244—253). 
Die Arbeit von Quanjer („Die Necrose des Phloems der Kartoffel¬ 
pflanze als Ursache der Blattrollkrankheit“) bringt neue Beweise für die 
von Sorauer vertretene Ansicht von der nichtparasitären Ursache der 
Blattrollkrankheit. Es wird im Anschluß an die Besprechung dieser 
Arbeit darauf hingewiesen, wie notwendig es wäre, genaue Untersuchungen 
über physiologische und anatomische Veränderungen bei Prüfung des Ein¬ 
flusses der einzelnen Wachstumsfactoren unter extremen Verhältnissen 
anzustellen. Es könnten dadurch künstliche Krankheitserscheinungen er¬ 
zielt werden, durch deren Kenntnis erst eine richtige Würdigung der 
natürlichen Krankheitserscheinungen angebahnt würde. 
Rippel (Augustenberg). 
MORSE, W. J., Powdery Scab of Potatoes in the United States 
(Science, N. S., 1913, 38 [11 July], 61—62). 
An examination of a considerable number of scabby Potatoes from 
the state of Maine and elsewhere showed only the presence of Rhizoc¬ 
tonia and Oospora. However, certain tubers showing pronounced surface 
pits lined with Rhizoctonia threads were planted under sterile conditions 
and in two cases typical Powdery scab developed. This led to a 
reexamination of the original material in which a number of the Spongo- 
spora spore-balls were found. These samples came from Massachusetts 
and Nebraska and indicate that possibly this newly-discovered American 
parasite may be a factor in the cause of Potato scab in this country. 
Humphrey (Madison, Wise.). 
