BIOPOLYMER AND TRICHODERMA HARZIANUM COMPATIBILITY FOR SUNFLOWER SEED COATING

Seed production demands the progressive replacement of insecticides and fungicides with natural and easily degradable products. Biopolymers and coating technology can be combined to meet that goal. This study proposes chitosan, sodium alginate and Trichoderma harzianum formulations that can be applied to sunflower seeds, maintaining their quality and safe storage. The aim of this study was to analyse the effect of coating with different chitosan and sodium alginate combinations on Trichoderma harzianum viability and sunflower seed quality. Sunflower seeds were coated with Trichoderma harzianum powder mixed with different biopolymer formulations (chitosan at 1% and 3%, sodium alginate at 1.5 %). Trichoderma viability was evaluated over time, through colonyforming units per ml. Sunflower seed quality was determined by, radicle emergence, germination percentage, root seedling growth and field emergence. Chitosan applied as seed coating had harmful
effects on Trichoderma viability and sunflower seed quality. Instead, sodium alginate not only improved the adherence and survival of Trichoderma harzianum strains but also maintained the radicle emergence, root growth and germination levels. Sodium alginate creates a protective film for Trichoderma harzianum strains from chitosan damaging effect, ensuring adequate storage of sunflower seeds.