Germination and Vigor of Crambe Seeds Treated with Polymers under Hydric Stress

摘要

Seed treatment with polymers can be favorable for germination and the establishment of plants in deficient or hydric saturated soils. This study aimed to determine the effectiveness of the treatment with polymers under different conditions of substrate water availability on the physiological quality of crambe seeds. The seeds of 2 lots with a germination of 82 and 69% underwent the following treatments: Lot 1 with and without polymer and lot 2 with and without polymer. The polymer used was Solid Resin GV5 at a dose of 0.6 mL kg-1 of seeds. In gerbox, the seeds were evaluated by germination, first counting, shoot and radicle length and seedling dry mass tests. In trays, the seeds were sown in sand substrate and humidity kept at 80, 60, 40, 20 and 10% of capacity retention. Seedlings were evaluated speed emergency index, sand emergency, shoot and radicle length and seedling dry mass tests. Researchers used a complete randomized 2x2 factorial block design (lotxpolymer) for tests carried out in gerbox and a 2x2x6 factorial block design (lotxpolymerxcapacity retention) for tests carried out on trays. The best seed physiological performance is obtained at a capacity retention of 40%; however the germination of seedlings is not affected until the capacity retention ranges from 20-60% showing the species tolerance to water deficit conditions. Film coating is favorable to good physiological quality seeds but it also shows no change for low vigor crambe seeds.