Small and Bush Fruits: Gooseberries 151 



This is not considered as a serious disease, at all events in Britain, 

 and but rarely does real injury to the plants attacked; but as so many 

 diseases, usually insignificant, suddenly, for some unknown reason, become 

 destructive parasites, it is wise to arrest their development. 



Spraying with half-strength Bordeaux mixture, or with a solution 

 of potassium sulphide, on the first appearance of the mildew, will arrest 

 its spread. Presumably the ground under the bushes- will be turned 

 over during the winter. This will bury all dead and infected leaves, 

 otherwise there will be a possibility, or almost certainty, of infection 

 the following season. 



Gooseberry Collar Rot (Sclerotinia fuckeliana). This is a very 

 destructive and widely diffused disease, but with prompt attention can 

 readily be detected and checked in its career. Gooseberries are most 

 frequently attacked, although Black- and Red-currant bushes sometimes 

 show the disease. The most usual symptom of the presence of this 

 parasite is the sudden wilting of the foliage of a branch, or sometimes 

 of the entire bush. This may occur soon after the leaf buds have 

 expanded, or later in the season when the bush is in full leaf. 



The conidial form of the fungus, called Botrytis, is responsible for 

 the mischief done, the higher or Sclerotinia stage being rarely, if ever, 

 produced, at least in this country. The fungus is a wound parasite, 

 and enters the stem at the collar through some small wound. When 

 once in the tissues the mycelium spreads in the bark and wood. If it 

 completely girdles the stem the whole bush dies; but more frequently 

 it attacks one main branch at its base, and when the mycelium of the 

 fungus has increased to such an extent as to cut off the supply of 

 water taken up by the root, wilting, followed by the death of the part 

 affected, is the result. Soon after the wilting of the leaves, tufts of a 

 grey or mouse - coloured mould burst through the bark at the base of 

 the diseased branch, which, if not soon removed, will gradually become 

 covered with the mould or Botrytis form of the fungus. If the diseased 

 branch is promptly removed the remainder of the bush may continue to 

 flourish, although so far as my own experience is concerned this is not 

 the case; the mycelium from the diseased branch having spread into 

 adjoining parts, and year by year additional branches die. Taking every- 

 thing into consideration, I think the most economical course is to remove 

 and burn the bush when once it is clearly established that it is infected. 

 Diseased bushes should be burned at once, for in addition to the great 

 number of Botrytis spores that would continue to be produced on the 

 dead wood, numerous small black bodies termed sclerotia develop on the 

 dead bark. These eventually fall away and give origin to Botrytis spores. 



Young shoots are also often attacked, and die back for some distance, 

 hence the popular name of " Die-back " amongst market gardeners. It is 

 well to remove and burn all such as soon as observed, to prevent further 

 infection. 



Finally, the leaves and also the fruit are sometimes injured by the 



