INSECT AND FUNGOUS PESTS 41 



the germination of peas and doubtless other legu- 

 minous seed is lowered by 10 days' exposure to car- 

 bon bisulphide fumes. Trybom 8 states that the pea 

 was attacked by a number of species of the 

 physopoda. He mentions particularly physopos 

 robusta, which attacks the field as well as the garden 

 pea. 



Pea Blight or Leaf Spot (Ascochyta Pisi). This 

 is the most prominent fungous disease to which peas 

 are heir, which corresponds to the anthracnose of 

 the bean. Discolored areas of dead tissue are noted 

 on the pea stems. The attack is usually more pro- 

 nounced near the ground. The leaves are also at- 

 tacked and show round or oval discolored spots 

 from one-fourth to one-half inch in diameter. On 

 the pods the disease appears as sunken spots like 

 those of bean anthracnose, only paler in color. 

 The fungus works through the pod and on to the 

 seed, thus infecting it. 



The treatment starts with planting seed free 

 from the disease. This can be guaranteed by select- 

 ing pods that are free from the trouble, or by getting 

 seed from sections where the disease is not preva- 

 lent. Spraying with bordeaux, beginning when 

 plants are from four to ten inches high and repeat- 

 ing at intervals of four to five days, will do much 

 toward controlling the disease. In a large way this 

 would not be practical. Sturgis 9 gives it as his 

 opinion that fungous attack is not primarily above 

 ground, but that it may be present in the seed. In 

 addition to planting clean seed he urges that grow- 

 ers avoid planting on land where peas have not been 



8 E. S. R., Vol. ii. 



Ct. Exper. Sta. Rpt. for 1899, p. 277. 



