54 BACTERIAL DISEASES OF PLANTS 



The Philippines. — In Luzon, citrus canker, a bud-rot of coco- 

 nut, brown rot of potatoes and egg plants, a leaf spot of tobacco, 

 bean blight, a bacterial rot of bananas and Musa textilis, and some 

 other diseases occur. Most of the islands are pathologically 

 unexplored. According to Reinking (The Philippine Journal 

 of Science, Vol. XIV, Jan., 1919, pp. 131-151) the coconut bud- 

 rot of the Philippines is due to Phy to phthora faberi Maubl., Bacil- 

 lus coli and a schizomycete resembling B. coli isolated from the 

 rotting palm bud may aggravate the rot but cannot initiate 

 it except under very favorable conditions of moisture and pre- 

 vious injury. 



India. — The brown rot of Solanacece is common and destruc- 

 tive. Citrus canker is common especially in the Punjab (Hutch- 

 inson, in a letter to the writer). There is also a bacterial disease 

 of the opium poppy. Most of Asia is a terra incognita. 



South Africa. — The mango disease in recent years has greatly 

 reduced the exports. Potato and tomato wilts are common. 

 There is a serious tobacco disease, probably bacterial. Crown 

 gall is common and injurious on shade and orchard trees. An- 

 gular leaf-spot of cotton is prevalent. Other bacterial diseases 

 occur, including several on citrus. Nothing is known about the 

 greater part of Africa. 



South America. — There is a serious disease of sugar-cane 

 in Brazil and another in Argentina, both of which I believe are 

 of bacterial origin and identical with Cobb's disease, but this 

 remains to be proved. Bondar has reported a destructive mani- 

 hot disease. The bud-rot of the coconut occurs in the north. 

 The banana disease of Guiana, however, is due to Fusarium 

 cubense. Most of South America, like Asia, is unexplored. 



United States and Canada. — Potato rots of which we have 

 several distinct forms, probably cause the greatest losses, one 

 year with another. Following these I should think pear and 

 apple blight. Perhaps the latter should be placed first, for the 

 destruction of an acre of potatoes would scarcely equal the value 

 of a single fine pear tree, and thousands are destroyed every 

 year. In California, which was formerly free from pear bhght, 

 the losses in the last twenty years have been enormous, amounting 

 to about one-third of all the full-grown orchards and to a money- 



