Programmable chitosan-based double layer seed coating for biotic and abiotic-stress tolerance in groundnut

In the face of agricultural challenges posed by both abiotic and biotic stressors, phytopathogens emerge as formidable threats to crop productivity. Conventional methods, involving the use of pesticides and microbes, often lead to unintended consequences. In addressing this issue, ICAR-Indian Institute of Oilseeds Research (ICAR-IIOR) has developed a chitosan-based double-layer seed coating. Emphasizing crop input compatibility, entrapment, and characterization, the study has yielded promising results. The double-layer coating on groundnut seeds enhanced germination and seedling vigor. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed the structural changes and entrapment of crop inputs. The persistence of T. harzianum (Th4d) and Bradyrhizobium sp. in chitosan blended film in studied soils revealed that viable propogules of Th4d were recorded in double layer treatment combination with 3.54 and 3.50 Log CFUs/g of soil (colony forming units) and Bradyrhizobium sp. with 5.34 and 5.27 Log CFUs/g of soil at 90 days after application (DAA). Root colonization efficacy studies of Th4d and Bradyrhizobium sp. in groundnut crop in studied soils revealed that, maximum viable colonies were observed at 45 days after sowing (DAS). This comprehensive study highlights the potential of chitosan-based double-layer seed coating providing a promising and sustainable strategy for stress management in agriculture.