Treatment with nitric oxide and seed coat removal improve germination and growth of rubber (Hevea brasiliensis)

Studies were carried out on the effect of seed coat removal and nitric oxide (NO) donor sodium nitroprusside (SNP) treatment on germination and growth of seedling and budded plants of rubber (Hevea brasiliensis). Interaction effects were observed between seed coat treatment and SNP treatments for germination time and percentage germination. Decoated seeds germinated earlier and improved synchronicity than intact seeds (with seed coat) and achieved 50% germination within nine days. SNP treatment at all four concentrations (20, 50, 100 and 200 μM) hastened the germination and increased the percentage germination especially when decoated seeds were used. Shoot and root attributes of seedlings (stock plants) derived from the seeds treated with SNP, especially at 50-100 μM, were significantly improved as compared to those from control and mock treated seeds. Growth of the budded plants were better when stock plants derived from SNP treated seeds were used. Therefore, NO treatment coupled with decoating could effectively be utilized to improve the germination and growth of seedling and budded plants of rubber. To our knowledge, this is the first report on redox priming of rubber seeds with SNP.