Abstract
Rice blast is the most harmful disease caused by Magnaporthe oryzae (M.oryzae), leading to yield loss.The aim of the work is to improve the resistance of rice to blast by introducing pyramid genes using conventional breeding and modern Marker Assisted Selection (MAS) techniques.Pyramiding is the combination of several resistance genes in one genotype, which improves the resistance of rice to pathogens.In this study, 7 pyramidal lines were identified with the introduction of a combination of 2 blast resistance genes (Pi-1 and Pi-ta) into 6 hybrids and 3 genes (Pi-1, Pi-33 and Pi-ta) into 1 line.Phytopathological testing of local rice cultivars and pyramidal lines showed that 3 out of 7 pyramidal lines were moderate resistant: 2 lines (F2 Bakanasski/7667 var.vulgaris and F2 Aisaule/7664 var.italica), containing 2 resistance genes (Pi-1 and Pita) and 1 line-F2 Aisaule/7689 var.zeravschanica, carrying 3 genes (Pi-1, Pi-33 and Pi-ta), while the local cultivars Bakanasski, Aisaule, and Aru, containing the blast resistance gene Pi-2, are susceptible.As a result, the blast resistance of rice was improved by creating pyramidal lines.Pyramided lines can be used for germplasm exchange and in rice breeding programs to improve blast resistance in rice.