DISEASES OF PLANTS. 251 



Strength before leaf fall aiul 5 per cent in February or March before the young 

 leaves api)ear. 



Experiments on the prevention of olive bacteriosis, G. Bellini {Coltivatore, 

 57 (1911), No. 32, pp. J/31-J/33; abs. in Internat. Inst. Agr. [Romc^, Bui. Bur. 

 Agr. Intel, and Plant Diseases, S (1912), No. 1, p. Sii).— The author describes 

 the results of experiments carried on in Tuscany on the prevention of the spread 

 of the olive bacteriosis, due to Bacillus olece. 



In April, 1910, a hailstorm severely injured a large olive plantation. The small 

 branches which had been injured by hail were cut from the trees, after which the 

 limbs and trunk of the tree received a strong apiilication of iron sulphate, con- 

 sisting of iron sulphate 15 kg., lime 15 kg., and water 100 liters. At the same 

 time the trees were s])rayed with a dilute Bordeaux mixture composed of 0.8 kg. 

 of copper sulphate, 0.8 kg. lime, and 100 liters of water. The bacterial tumors 

 were cut out wherever observed and the cut surfaces treated with the mixture 

 composed of iron sulphate and lime. 



At the close of 1911 no evidence of bacteriosis was to be seen on any of the 

 trees. The growth during the summer had been exceptionally vigorous, and 

 the prospect for a large yield the next year was considered quite promising. 



Glososporiose of the Japanese persimmon, S. Ito (Bot. Mag. [Tokyo], 25 

 (1911), No. 296, pp. 191-201, flgx. 2; ab.s. in Internat. Inst. Agr. [Romr\. Bui. 

 Bur. Agr. Intel, and Plant Diseases, 3 (1912), No. 1, p. 321). — In 1910 the 

 author collected and examined a number of specimens of diseased fruit of the 

 Japanese persimmon (Diospyros kaki). The present study was undertaken to 

 determine the cause of this disease, which sometimes occasions considerable 

 loss. Badly affected trees are known not to pro<luce fruit for 3 years. 



The symptoms of the disease may be recognize<l by the appearance in the 

 middle or latter part of July of small spots on the unripe fruit. These are 

 black, of varying sizes, from that of a pin head to from 1 to 2.5 cm. in diameter, 

 circular or elliptical in outline, and frequently bordered by a yellowish brown 

 ring. By the coalescence of a number of these .';i)ots a considerable area of the 

 fruit may become involved. The affected fruits usually fall to the ground 

 before ripening, and decomposition is hastened by other fungi. The fungus is 

 also capable of attacking fruits in storage. 



Inoculation experiments showed that the fungus can be readily transferred 

 to ripe apples when the spores are inoculated on the wounded surface, but 

 the reciprocal infection of the spores of Glomerella rufomaculans on green per- 

 fsimmons always gave negative results. 



The fungus causing this disease is believed to have been hitherto undescribed, 

 and the name Glccosporium kaki n. sp. is given it. 



The cause of mottled leaf, R. R. Snowden (Fla. Ch'O^ver, 6. (1912), No. 2, pp. 

 3, -}). — The author believes that he has traced several cases of malnutrition 

 {:nd incipient chlorosis or mottled leaf in orange and lemon trees to an excessive 

 proportion of magnesia to lime in the soil. Ash analyses of leaves from healthy 

 and sick lemon trees showed that in the leaves from the sick plants the per- 

 centage of potash was more than doubled and phosphoric acid increased by 11^ 

 times, while lime was reduced about 50 per cent. 



An examination of the soil about thrifty and diseased plants indicated that 

 the magnesia-lime ratio for oranges should not fall below 1 part of magnesia to 

 2 of lime. For lemons the ratio of 1 : 0.84 was suflBcient to maintain good color 

 in the foliage. Below that figure the leaves became mottled or decidedly yellow. 



The bud rot of the coconut in Ceylon, N. Patouillard (Jour. Agr. Trop., 11 

 (1911), No. 121t, pp. 315, 316; abs. in Internal. Inst. Agr. [Rome], Bui. Bur. 

 Agr. Intel, and Plant Diseases, 3 (1912), No. 1, pp. 319, 320).— The author 



