1908.] Insect, Fungus, and other Pests. 439 



months. A second kind of conidia require a period of rest 

 before germination takes place. The sporangia possess a 

 single tube-like projection into which the protoplasm passes 

 and forms a sphere at its tip, which breaks up into biciliate 

 zoospores. 



Both oospores and resting conidia remain on the ground 

 and produce zoospores after a period of hibernation. 



This disease only occurs where the ground is very wet and 

 the light dull. If seed beds are formed where the drainage is 

 good and a fair share of sunshine allowed, the fungus is com- 

 pletely held in check, as its reproduction and diffusion depend 

 entirely on the constant presence of water in the soil. 



Diseased Peas. — Peas from Bristol and Manchester were 

 attacked by a root fungus, Thielavia basicola, Zopf. When 

 once the plants are infected it is very difficult to arrest this 

 disease. Watering with a solution of sulphate of potash 

 checks the spread of the fungus in the soil ; a dressing of soot 

 is also useful. When the diseased crop has been removed the 

 infected soil should be dressed with quicklime. 



Pea plants from Falmouth were infested with pea spot, 

 caused by the fungus Ascochyta pisi, Libert. Failure of the 

 plants, however, was not due to the fungus, but to root troubles, 

 the exact nature of which could, not be determined. 



Gooseberry and Currant Leaf-Spot. — Black currant specimens 

 from St. Mary Cray and Norwich, and gooseberry specimens 

 from Fakenham and Shanklin, were found to be infested with 

 the Gooseberry and Currant Leaf-spot, Gloeosporium ribis, 

 Mont. Injured leaves fall early in the season, and as the 

 disease usually increases in intensity each succeeding season, 

 the bushes are weakened and eventually killed if nothing be 

 done to arrest the disease. 



It is important that all diseased leaves should be collected 

 and burned. During winter the ground under and around 

 the bushes that have been infected should be turned over and 

 dressed with lime. In the next spring, just at the time when 

 the leaf buds are expanding, a thorough spraying with a solution 

 of potassium sulphide (liver of sulphur), 1 oz. in 4 gallons of 

 water, should be given. A second spraying should be given 

 after an interval of three weeks. 



Diseased Roses. — From Westbury (Wilts) and Longfield 



