Characterization of newly recorded <i>Pythium mamillatum</i> AJA, causing cucumber root rot in Iraq: Implications for disease management in sustainable agriculture

Pythium mamillatum is an emerging pathogen responsible for root rot and wilt diseases in cucumber (Cucumis sativus), resulting in significant crop losses in Iraq. The present study examined the occurrence, distribution, pathogenicity, and genetic characterization of P. mamillatum strain AJA in Iraq, with broader implications for sustainable agricultural practices. Field surveys were conducted to collect symptomatic cucumber root samples from Al-Tahiria, Al-Azizia, and Al-Badah districts revealed disease incidences of 37%, 35%, and 21%, respectively. Infected plants exhibited symptoms of root rot and wilting. According to molecular research, the Iraqi strain, Pythium mamillatum AJA, accession No. MN460315.1 was 100% genetically related to strains from China, the USA, and Canada, indicating a shared evolutionary origin. Through inhibiting seed germination from 10% on the third day to 90% on the seventh day of inoculation, P. mamillatum (strain AJA) demonstrated significant losses to local Iraqi cucumber crops. The rapid spread of agriculture, its valuable genetic similarity with strains established in other regions worldwide, and its pathogenic viewpoint highlight its increasing threat. The study emphasizes the importance of employing effective disease control techniques within the framework of sustainable agriculture. Reducing the effect of this infection mostly depends on early identification, seed treatments, and constant pathogen monitoring. Maintaining crop health and guaranteeing long-term agricultural resilience also depend on sustainable farming methods that reduce the use of chemical pesticides and advance integrated pest management (IPM).