Seed Health Techniques for Detection and Management of Alternaria spp. in Sesame

Abstract

Sesame (Sesamum indicum L.) is a vital oilseed crop, renowned for its high protein content, superior oil quality, and antioxidant properties, and is extensively cultivated across India and Asia. However, the productivity and quality of sesame are severely affected by Alternaria leaf spot, primarily caused by Alternaria sesami and Alternaria alternata. The disease leads to significant yield losses, as seed infection correlates directly with reduced germination, seedling stand, and crop yield, with losses ranging from 4% to 25% depending on the severity. Different stages of plant growth exhibit varying susceptibility, with the greatest vulnerability occurring in plants inoculated at 8 to 12 weeks. Furthermore, Alternaria species, including A. sesami and A. sesamicola, are major seed-borne pathogens, with infection levels as low as 2% potentially causing substantial losses. ; To manage these risks, a variety of seed treatment methods, including fungicides, biocontrol agents, and plant extracts, have been explored, demonstrating promising results in controlling disease incidence and improving seed quality (Bhattiprolu et al., 2023. Several seed health testing methods, including the standard blotter method, deep freezing blotter method, and PCR-based molecular techniques, offer effective means for detecting seed-borne Alternaria species. Molecular methods, particularly PCR and LAMP assays, provide rapid, sensitive, and specific detection of Alternaria species, enabling early diagnosis and better disease management. Additionally, serological methods like ELISA have shown potential in pathogen detection, although molecular techniques are preferred for their higher sensitivity and specificity. This review underscores the importance of effective monitoring and management strategies to mitigate the impact of Alternaria diseases on sesame production, highlighting the relevance of diverse diagnostic approaches in managing this crop pathogen.