Abstract
One hundred and ninty seven advance lines/varieties were sown on Isi of November and December, 2000 at Department of Plant Pathology. University of Agriculture, Faisalabd. The nursery was inoculated with Puccinia recondita f. sp, tritici and natural inoculum was also relied upon for infection. Based on a leaf rust severity scale 89 lines/varieties were free from disease symptoms, 43 lines/varieties were resistant, 32 moderately resistant, 10 moderately susceptible. 16 susceptible and 7 were highly susceptible in early sown nursery. In late sown nursery 74 were asymptomatic, 28 were resistant, 31 moderately resistant. 8 moderately susceptible, 17 susceptible and 39 highly susceptible. There were no symptoms of yellow rust in either early or late sown nurseries, Majority of lines/varieties sown on Isi of December had significantly higher leaf rust severity compared to the similar gerrnplasrn sown on Isi November. Commercially grown wheat varieties i.e. Inqilab 91. Bahawalpur 97, MH 97. Kohistan 97 and Iqbal 99 had no leaf rust symptoms indicating their resistance status against the disease. Eiuhtv nine and 74 lines/varieties in earlv and late sown nursery respectively, were free of any disease symptoms or insect attack indicating their good genetic potential which can be exploited for breeding against disease and pest resistance in future. Key words: leaf rust, Puccinia recondite f sp. tritici, wheat, resistance. susceptibility