Gray Mold
Gray mold, caused by the fungus Botrytis cinerea, can cause serious yield losses of peas growing in humid conditions. The fungus is a common pathogen of many crops including lentils, beans, sunflowers and buckwheat. It can also function efficiently as a saprophyte on dead and dying plant material.

Appearance: The first symptoms usually observed are on the lower leaves during or after flowering. Under humid conditions the leaves appear fuzzy because of the masses of spores produced. As infection progresses, infected leaves become dry, gray and shriveled and eventually fall off.

Pod damage is the main cause of economic loss. Small, oval, tan, water-soaked spots develop on pods often at sites where petals have fallen. Senescent petals provide a food source for the fungus and also help to maintain humidity. Mature spots are grayish, slightly sunken and sometimes include small black specks.

Disease Cycle: Botrytis over-winters in infected seed or on debris of numerous host plants. Spores of Botrytis move in splashing water, in air, in irrigation water and on farm machinery. The severity of the disease is dependent mainly on weather conditions during he growing season. Wet weather contributes to disease build-up by providing suitable conditions for spore production and plant infection.

Disease Control:
a) Use disease-free or lightly infected seed.
b) Potassium should be applied if this element is deficient in the soil. Potassium deficiencies have been reported to make pods more susceptible to gray mold.

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Discovery Seed Labs Ltd.
450 Melville Street
Saskatoon, Saskatchewan
S7J 4M2

Phone:(306)249-4484
Fax:(306)249-4434