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THE NURSERY-MANUAL 



FIG. 214. Anthracnose of 

 currant. 



ANTHRACNOSE OF CURRANTS AND GOOSEBERRIES. The 

 anthracnose disease often causes heavy defoliation of nursery 

 stock early in the season. Usually 

 the currants are more severely affected 

 than the gooseberries. 



Description. The disease appears 

 on the leaves as small circular spots, 

 dark brown in color and about one 

 twenty-fifth of an inch in diameter 

 (Fig. 214). Severely affected foliage 

 soon turns yellow and falls prematurely. 

 Cause. The disease is caused by 

 the fungus Pseudopeziza ribis. Spores 

 of the fungus are produced in the spots on the leaves and 

 being carried by wind and rain to other leaves the spores 

 germinate and produce new infections. Special fruiting bodies 

 (apothecia) of the fungus develop in the diseased leaves 

 which fall to the ground and these apothecia serve to bridge 

 the fungus over winter. In the spring, spores are produced 

 which affect the new foliage. 



Control. Spraying the bushes with 

 lime-sulfur solution 1 to 40, or dusting 

 with a mixture of 95 parts finely ground 

 sulfur to 5 parts powdered arsenate of 

 lead, has proved effective in controlling 

 the anthracnose. It is advisable to 

 make the first application when the 

 leaves are unfolding and other applica- 

 tions at intervals of ten to twenty days 

 until about five or six treatments have FlG - ? 15 - Se P toria leaf ; 



. , spot oi gooseberry and 



been made. currant. 



SEPTORIA LEAF-SPOT OF CURRANTS AND GOOSEBERRIES. 

 The septoria leaf-spot occurs on various species of Ribes. It 



