Question

Powdery mildew of Pea is caused by:
a. Puccinia
b. Erysiphe
c. Ustilago
d. Alternaria

Answer 1

Hint: Powdery mildew is a type of fungal disease. It affects a wide range of plants. This disease of the plants can be identified easily, as its symptoms are very distinguishable. The plant is infected with the problems that show white powdery spots on the leaves and stems.

Complete answer:
Powdery mildew is a very serious disease which is noticed in the field of peas. This generally occurs when warm humid conditions favors the growth of peas late in the season. The seeds that are obtained from the infected pods are looking discolored and they are also less tasty than normal seeds.

The plants that are suffering from the disease powdery mildew are usually covered with a white powdery film. It is the main symptom of this disease. If the plant is severely infected then The leaves of the plant turn blue-white in colour. The tissue present below these infected areas may take a purple colour. All aerial parts of the plant are infected by the problem which leads to the withering of the whole plant.

If the pod of the peas is infected severely, then it can cause a grey-brown discoloration of the seeds. These seeds have an odious flavor that causes a downfall in the quality of the grain.

> Option B: The disease of powdery mildew on the pea plant is caused due to Erysiphe pisi. It is also reported that these diseases may be caused by some other fungi such as Erysiphe trifolii and Erysiphe baeumler. All these belong to the order of Erysiphe.

> Option A: Puccinia is also an order of fungi which causes black stem rust of wheat. Generally, it is used to elaborate on the processes of infection which are utilised by rusts to move between two species of the host plant.

> Option C: Loose smut in barley is a type of disease caused by the fungus Ustilago. The fungus attacks the growing barley plant when it is flowering.

> Option D: Alternaria is a type of fungus which has been considered for causing spots on the leaves and other diseases on over different host species of plant.

Hence, the correct answer is option (B).

Note: Powdery mildew is a disease which is observed in the pea plants. In this disease, the plant usually covers with the white powdery film. It is caused by the fungus Erysiphe. Generally, the seeds collected from the pods of the infected plant get discolored and lose their nutritional value.