Annual Recurrence of Black Rust of Wheat in India

Annual Reoccurrence of Black Rust of Wheat in India:- In 1933, late professor K. C. Mehta worked on the problem of annual recurrence of rust in India and solved the mystery. He proved that the uredospore’s produced on the hills are responsible for the annual recurrence of rust disease in the plains of India. According to him:

(a) Uredospore’s can survive in the summer in hills (at higher altitude of 1300-2500 metres).

(b) They survive on self sown wheat plants and tillers. The atmospheric conditions on high altitude and the low temperature help for the survival of uredospore’s.

(c) In the hills the wheat crop is sown in September and October, its gets infected very soon whereas in the p’.j -.s of India the wheat crop is sown in the months of October and November. At that time the hilly crop is already heavily infected by rust disease. The wheat plants are infected by the uredospore’s survived during the summer season in hills.

(d) These uredospore’s are easily carried away by wind and first infect wheat crop in January and February. Thus, he concluded that uredospore’s produced on the hilly crops particularly in the region of Himalayas, Nepal hills for northern plains and Nilgiri.

Palni hills and Panchgani of Western Ghats for the southern plains are the causal organisms for the annual recurrence of the rust disease in the plains of India. He also suggested that the rust severity in the plains can be reduced if there is no wheat cultivation on the hills for some time.