Evaluation of indigenous rice germplasm for identification of durable bacterial blight (Xanthomonas oryzae pv. oryzae) resistance sources in Bangladesh

Bacterial blight disease caused by Xanthomonas oryzae pv. oryzae (Xoo)is one of the most devastating biotic stresses of rice in all rice growing countries of the world. Find out the resistant source is the first step for the development of resistant rice variety through breeding techniques. In this experiment, one hundred land races including susceptible check Purbachi and resistance check IRBB65 were screened both in seedling and maximum tillering stages. BXO9, a representative isolate of the major races of BB pathogen of Bangladesh was used for inoculation. The results were analyzed through multivariate analysis viz. Principal component analysis (PCA), Principal coordinate analysis (PCO), Canonical vector analysis (CVA) and Cluster analysis (CLSA) using GENSTAT 5. The genotypes were grouped into ten clusters based on lesion length on leaves, relative lesion length and leaf area damaged. In nursery experiment, cluster VI contained 4 genotypes including Purbachi and cluster I comprised 2 entries including IRBB65. In field experiment, cluster V contained 9 land races including Purbachi and cluster I contained 7 land races including IRBB65. In nursery experiment SUNGWALA, PAJRE and in field experiment MATHIA and HARMA SHAIL (1) showed resistance against Xoo. However, further research is necessary for the confirmation of these materials as resistant source both at seedling and maximum tillering stages using molecular markers.