49 



Article 6 of this Order and all previous Orders relating to the 

 sale of gooseberries (fruit), affected with this disease, are now 

 revoked, so that any gooseberries fit for human consumption 

 may be sold in all markets and shops. 



On and after 1st October, 1921, the importation of goose- 

 berry and currant bushes and of gooseberries (fruit) into 

 England and Wales, from any place abroad other than the 

 Channel Islands, is permitted .provided they are accompanied 

 by a certificate issued by the exporting country to the effect 

 that they are healthy and free from disease. (Destructive 

 Insects and Pests Order of 1921.) 



Further information with regard to either of these Orders 

 can be obtained on application to the Ministry. 



EUROPEAN GOOSEBERRY MILDEW. 



(Microsphaera* grossulariae, Lev.) 



The gooseberry plant is attacked by two distinct mildews, 

 termed respectively the European Gooseberry Mildew and 

 the American Gooseberry Mildew. The former, caused by 

 the fungus Microsphaera grossulariae is the only one dealt 

 with in the present leaflet. TEe latter, caused by an entirely 

 different fungus, is a very much more serious pest and will 

 be found described in Leaflet No. 195. 



The two mildews, though somewhat similar in certain 

 stages, can with a little experience usually be distinguished 

 ^ven with the naked eye. The European Gooseberry Mil- 

 dew occurs on the upper side of the leaves in the form of a 

 very delicate white mould or mildew. In the early stages it 

 is coated with a distinctly mealy substance. As is the case 

 with all true mildews the mycelium (spawn) is quite super- 

 ficial, although, in order to obtain the nourishment it requires, 

 the fungus sends down minute suckers into the cells of the 

 attacked leaf. The white mealy substance consists of masses 

 of spores. These spores are termed conidia or " summer 

 spores," and, being carried by insects. or being blown about 

 by the wind, bring about the infection of other leaves. As a 

 rule the mildew is confined to the upper surface of the leal, 

 but occasionally it is found on the under surface and also on 

 the berries. 



Later in the season the fungus produces a second form of 

 fruit. These consist of minute spherical spore-cases (peri- 

 thecia) which contain the " winter spores "or " resting 

 spores." They occur on the mildewed patches and appear 

 first as yellow specks just visible to the naked eye^ but 

 mamalely become black. In autumn the spore-cases either 

 fnll off the leaves or fall to the ground with the leaves. They 



