Morpho-molecular characterization revealed distinct diversity among rice blast (Pyricularia oryzae) isolates

• Published in: Indian phytopathology 2024, Vol.77 (2), p.491-499
• Main Authors: Hasan, M. M., Akter, Marufa, Saha, Sumitra, Malek, Md. A., Islam, Nazmul, Alam, Md. Amirul
• Format: Article
• Language: English
• Subjects: Biomedical and Life Sciences; Life Sciences; Plant Pathology; Research Article
• ISSN: 0367-973X; 2248-9800
• DOI: 10.1007/s42360-024-00749-7

Rice blast disease stands as one of the world’s most devastating afflictions, stemming from the ascomycete fungus Pyricularia oryzae . This malevolent force significantly diminishes rice yields in countries reliant on rice cultivation. Unraveling effective strategies to manage this perilous disease hinges upon a profound understanding of the morphological traits and genetic diversity exhibited by the pathogenic isolates. This study aimed to traverse the rice-growing zones of Bangladesh, gathering, identifying, and characterizing the rice blast pathogen P. oryzae . Nineteen isolates underwent scrutiny based on various criteria such as colony color (ranging from dark brownish with a black border to blackish grey with a white edge, ashy with a concentric ring, and grey), colony form (irregular and regular), growth rate, conidia morphology, and sporulation rate. To delve deeper into the genetic makeup, 9 SSR primers were employed to analyze the 19 isolates. The resulting fragment numbers spanned from six to fourteen. Remarkably, the population’s highest genetic variability surfaced with RM589 (0.9194), while RM5961 exhibited the least (0.759). The PIC (Polymorphism Information Content) values, indicating diversity among alleles and their frequency, ranged from 0.7216 to 0.9139. These findings underscored the dual diversity-both morphological and genetic-within the blast fungus population in Bangladesh. This research serves as a pivotal step towards fortifying our arsenal against blast disease. Identifying virulent genes, deciphering the intricate interactions between isolates and their hosts, and cultivating blast-resistant rice varieties all stand as crucial outcomes of this endeavor.