Rust diseases specifically leaf rust caused by Puccinia recondita. f.
sp. tritici, is globally important fungal of wheat (Triticum aestivum L.
em. Thell) that is responsible for significant yield losses; up to 40%
worldwide. Due to rapid change of pathogen races, single gene resistance
is short lived in wheat cultivars. Alternatively, a more durable form of
resistance is attributed to slow leaf rusting for which certain
genotypes have been identified and characterized. Genetic studies
indicate that slow rusting resistance is under polygenic control with
moderately high heritability. Such resistance is controlled by a number
of minor genes also referred to as adult plant resistance (APR) genes.
Although 10-12 slow rusting genes are known to be present in CIMMYT
spring wheat, only two genes Lr34 and Lr46 have been characterized for
slow rusting. The present research work was proposed to characterize the
effect of different slow rusting gene(s) on spread of leaf rust. This
was an indirect selection for desirable allele, to exploit the
advantages of the durability of slow rusting and to develop a better
understanding about its mechanism that might be of much promising in