Executive Summary : | Wheat is the second most important staple food crop and is a major source of meeting the daily calorific needs of people in developing countries Among biotic stresses, fungal diseases are among the most important constraints to wheat production and productivity. Major fungal diseases of wheat in India include rusts, Karnal bunt, leaf blight and powdery mildew. Karnal bunt has minimal impact on wheat yield which is, generally, less than 1% in areas infested with T. indica in India. Karnal bunt can severely reduce the quality and marketability of the wheat grain. Wheat lots having more than 3% infection reduces flour recovery, quality and palatability of whole meal due to fishy odour of trimethylamine and perceptible discoloration of the finished product because of black powdery mass of teliopores. Karnal bunt of wheat has significance in global wheat trade as mass of teliospore lying inside the pericarp of infected grains which impair the quality of seed and product derived thereof, if the infection in the seed lot exceeds 3%. Around 60-90% of world wheat production is traded annually between countries. As many as 65 wheat importing countries have imposed embargoes on import from Karnal bunt infected zones resulting in restriction in free trade of wheat as a consequence India the second largest producer of wheat in the world continues to disproportionately small share of international trade. In recent years many researchers have done lot of work in genetic analysis of resistance to Karnal bunt, mapping of major resistance genes and QTLs. In spite of this disease being economically important, the host resistance sources identified so far, are limited. The polygenic nature of resistance to this disease also adds to difficulty in identifying and using the host resistance to manage this disease. The importance of this disease has increased many folds in recent times with India producing record wheat for past many years now. The record produce has opened avenues for wheat export, however, Karnal bunt will remain an issue as many countries have zero tolerance to wheat infected with this disease. It is thus of prime importance to develop wheat cultivars with inbuilt resistance to Karnal bunt. Herein, we propose a project to characterize resistance to this disease in a panel of 350 wheat germplasm and identify new sources of resistance. The germplasm panel we have developed, consists of already know sources of resistance from India and CIMMYT, registered genetic stocks, many indigenous wheat lines with multiple disease resistance and recently released elite cultivars. A preliminary evaluation of this panel has revealed a wide variation for resistance to KB among the germplasm lines. Among the already known sources, eight (8) known genetic stocks along with eight (8) elite wheat cultivars were used in crossing to develop a 16-parent MAGIC population for further utilization in genetic studies. |