APPENDIX 



PEA AND BEAN MILDEW 

 (Peronospora viciae, De Bary.) 



Cultivated peas, broad beans, and tares are often 

 seriously infested by this parasite, which forms a dense 

 pinkish-grey felt on the leaves, more especially on the 

 under surface. In severe cases the young pods are also 

 attacked, but even when this is not the case the injury 

 done to the foliage alone is sufficient to destroy the crop. 



A second species, called Peronospora trifoliorum, De 

 Bary, mentioned on page 78, also attacks the plants 

 named above, and to the ordinary observer is indis- 

 tinguishable from P. viciae. Both are amendable to the 

 same line of treatment. 



PREVENTIVE MEANS. In the case of peas or broad 

 beans grown in gardens on a small scale, thorough dusting 

 with a mixture of powdered sulphur and quicklime at 

 intervals will hold the mildew in check. 



Both kinds of fungi mentioned above are common on 

 various wild plants belonging to the Leguminosae, and 

 from thence may pass on to cultivated plants. 



447 



