Question

Which of the following is a soil-borne disease?
(a) Red rot of sugarcane
(b) Rust of wheat
(c) Leaf spot of rice
(d) Smut of bajra

Answer 1

Hint: This disease causes direct loss of grain by replacing them with sori, and yield losses of up to 30% have been reported. The disease can be seen through the manifestation of its symptoms at the grain setting.

Complete answer:
Smut of bajra is a soil-borne disease that is present in most of the states where bajra (pearl millet) is cultivated. Tolyposporium penicillariae is the causal agent of pearl millet smut. The disease can be seen through the manifestation of its symptoms at the grain setting. A few grains generally get replaced by oval to top-shaped sori which are usually two or three times the size of the normal grain. They are bright-green to dirty-black in colour and often rupture to expose a black spore-mass. The colour is due to the membrane which is tough and is made up of host tissues. The spores are held together in the form of compact balls, which remain persistent even in water.

Additional information:
Smut disease of bajra commonly occurs in many parts of our country such as Tamil Nadu, Andhra Pradesh, and Maharashtra. The infection is visible on scattered grains in the ear and the majority of grains escape the damage.
The symptoms of Smut Disease are-
-The disease can be seen through the manifestation of its symptoms at the grain setting.
-A few grains generally get replaced by oval to top-shaped sori which are usually two or three times the size of the normal grain.
-They are bright-green to dirty-black in colour and often rupture to expose a black spore-mass.
-The colour is due to the membrane which is tough and is made up of host tissues.

So, the correct answer is 'Smut of bajra'.

Note:
The control measures recommended strongly for this Smut Disease are the removal of smutted ears, use of clean seeds, hot weather deep ploughing, field sanitation, and crop rotation. Attempts are required to raise resistant varieties of this crop against smut disease.