IMPACT OF RUST ON WHEAT PRODUCTION GLOBALLY: A REVIEW

On this planet earth, wheat is one of the main and old staple foods. Over past 40 years, significant yield gains of wheat results in balanced and steady supply in relation to demand. Fungus causes losses to different crops all over the world and these are also responsible for economical losses of wheat crop every year. Puccinia species of fungus i.e. Puccinia graminis, P. triticina and P. striiformis are responsible for wheat rust. Wheat rusts are the chief biotic constraints in the efforts to boost or prolong production. Worldwide wheat rusts are devastating and historic pathogen. Number of efforts is going on to counter the threat of namely stem or black rust (Puccinia graminis), stripe or yellow rust (Puccinia striiformis Westend) and leaf or brown rust (Puccinia triticina). Out of all three rusts, stem (black) rust is the less common but widely distributed rust around the world. The 40 per cent of world’s acreage is threatened by emergence of virulence Ug 99. In susceptible cultivars, the losses of stripe (yellow) rust reaches upto 100 per cent so it has economically important. Leaf (brown) rust is very problematic because of its adaptability in wide range of climate. Many cultivars have prolong resistance for past many years for different wheat rusts such as Americano 25, Americano 44d, Surpreza, Frontana and Fronteira for leaf rust or brown rust, Thatcher and Hope for stem rust or black rust and Wilhelmina, Capelle-Desprez, Manella, Juliana and Carstens VI for stripe rust or yellow rust. Chemical methods were also used to control rusts in many countries around the world.