Effect of storage on chemical composition, germination and vigour of dormant and non-dormant seeds of sunflower genotypes

Seeds of three sunflower genotypes EC-68415, 234-A and Morden showed dorman cy up to two months. Ethrel-treated seeds showed more than 80% germination at the end of one month. The untreated seeds of EC-68415 had 81% germinatio n even at the end of 11 months, but ethrel-treated seeds had less than 70% germination after eight months of storage. Ethrel treatment also reduced th e storability of seeds of other genotypes. The dry weight of seedlmgs obtai ned from ethrel-treated seeds declined faster during storage when compared to that of untreated seeds. The reducing sugar or non-reducing sugar conten t did not change significantly during storage of seeds. However protein and fatty acid content decreased due to ethrel treatment.