Q. Which of the following is a bacterial plant disease :
(a) Tikka disease of Groundnut
(b) Downy mildew of Grapes
(c) Ring rot of Potato
(d) Red rot of Sugarcane.
Solution : Correct option : C EXPLANATION: Ring rot of potato is caused by the bacterium Clavibacter michiganensis subsp. sependonicus. The primary symptoms of the plant disease are soft cheese-like rotting of the vascular ring and in severe cases, the skin of potato totally cracks. Tikka disease of groundnut is a fungal disease. Downy mildew of grapes is caused by Plasmopara viticola and it is a major disease of grapes. Red rot of sugarcane is caused by the fungus Colletotrichum falcatum. This disease is seen in Indian sub-continent.
