Epidemiology in the Indian Subcontinent

Publisher Summary In the Indian subcontinent, wheat (Triticum aestivum and T. durum) is one of the major winter cereals and the annual production is around 48–50 million metric tons. Wheat yields are affected by all the three rusts, stem rust, leaf rust, and stripe rust, in addition to various other diseases. As wheat is grown throughout the year in the Nilgiri and Palney Hills, there are wheat and other grass hosts available for the pathogen to survive on nearly all year. This chapter illustrates dispersal gradient of stem, leaf, and stripe rust from point source mapped after 75 days at Karnal, northwestern India. Climatic data shows that the number of rainy days is more important in determining the build-up of rusts over northwestern India than the amount of rainfall. Leaf rust effectively spreads to central India by wind and then is deposited by rain. Conditions that favor the transportation and deposition of leaf rust urediospores are identical with those for stem rust.