Investigations on some diseases of the pea plant in theGaspe district, Que.

An investigation of a disease outbreak causing severe damage on pea in Gaspe county has shown that two fungus diseases are reeponsible for practically all the losses. These are Ascochyta leaf and pod spot or blight oaused by Ascochyta pisi Lib. and Mycosphaerella blight oaused by Mycosphaerella (Berk and Blox). Stone. Laboratory experiemnts have shown that the pathogenic activities of these two blight producing fungi are favoured by cool moist conditions. This finding explains the epidemic nature of the two blights in Gaspe as compared to the rest of the province, sinca the climate in the pea-growing area of Gaspe is a cool and very moist one. Field tests on the value of dusting and spraying gave very satisfactory control in one year's trial. Bordeaux spray was somwhat better than sulphur dust and copodust wh1ch is a oopper dust. [...