Gooseberry Blight. 



203 



or conidia, are first formed, which are borne by the wind from 

 plant to plant and spread the disorder. Later on, the winter 

 spores, or resting spores, are formed, to carry the fungus on 

 through the winter. These are imperceptible with the naked 

 eye, but they may be seen with a glass late in July and 

 during the autumn in the form of dark brown bodies upon 

 the " felt-like coating." Upon examination of these bodies 

 with the microscope these are seen to be nearly globular with 

 cross markings on their surface, and bearing from seven to 

 eight slender, colourless filaments, with ends somewhat 

 fantastically branched, as shown in the figure. It is supposed 

 that these branched filaments keep the perithecia in place 

 upon the mycelium on the leaves. The perithecia contain 

 from four to eight asci^ nearly oval cases, in each of which 

 there are four or five spores. When the leaves fall the 

 perithecia fall with them, and remain upon the ground or on 

 the decaying leaves until the spring, when the asci burst and 

 the spores are liberated and speedily germinate in favourable 

 conditions. 



An allied species of fungus causes very much more 

 serious injury to gooseberry bushes in the United States, so 

 that it has lately been found almost impracticable to grow 

 there the finer varieties introduced from other countries. 

 The appearance and life history of this fungus are very 

 similar to those of the Microsphceria Grossularia, except that 

 the former infects the fruit as well as the leaves. 



Prevention aiid Remedies. 



The leaves from infected bushes should be raked from 

 under and round them and burnt. The ground round the 

 bushes should be dug or hoed deeply to bury the perithecia^ 

 and when the bushes are cut in the winter, every piece of 

 cutting should be raked up and burnt. Any dead leaves 

 remaining on infected trees should be, as far as possible, 

 picked off and burnt. 



Where there is a sign of infection the leaves should be 

 dusted thoroughly above and below with very finely 

 powdered sulphur put carefully on with a knapsack powder- 

 distributor on a still, hot, sunny day. 



