Study On The Genetics Of Resistance To Leaf Rust In Some Advanced Lines Of Wheat At Seedling Stage

Brown rust (Leaf rust) which caused by Puccinia recondita f. sp. tritici, is a worldwide major disease of wheat. In order to study the inheritance of resistance of the disease in wheat, a half diallel cross was made among wheat lines including N-75-1, N-75-8, N-75-11, N-75-13, N-75-15, N-75-20 and susceptible cultivar Bolani. Parents and F1 progenies were inoculated at seedling stage in the greenhouse by a pathotype of leaf rust. Latent period, (number of days from inoculation to appearance of the first uredia) and infection type were recorded 9-12 days after inoculation. Two procedures including Griffing, and links and Hayman methods were used to analyse the data. General combining ability (GCA) and specific combining ability (SCA) were statistically significant for both traits. Narrow-sense heritability and broad-sence heritability were estimated 55% and 92% for latent period and 58% and 94% for infection type, respectively. Results showed that line N-75-8 has more recessive genes for longer latent period and lower infection type.