Influence of storage conditions on viability and vigour of Sunflower (Helianthus annuus L.) seeds

Abstract

The storage experiment examined the effects of storage temperatures, seed moisture contents (SMC), and storage durations (SD) on the viability and vigour of sunflower seeds. Certified sunflower seeds were evaluated for germination, seedling vigour, and fungal infection. A 3x3x6 factorial experiment in CRD was set out in four replicates. The three factors were temperature (5, 20, 35 ºC), SMC (6,8,10%), and SD (15, 30, 45, 60, 75, 90 Days After Storage, DAS). Before storage (0 DAS), the initial germination percentage (GP=94%), Germination index (GI=322), Seedling vigour index (SVI=2118), and fungal infection incidence (FII=52%) were determined and used as control. The lowest GP of 73.83% and 75.5%, GI (276.08 and 283.2), SVI (1485 and 1530), and greatest FII (73.0 and 72.67%), were found in seeds stored at a temperature of 35 ºC and SMC of 10% respectively, at 90DAS. Upon the interaction effect of temperature and storage duration, the temperature of 5 ºC followed by the temperature of 20 ºC at 90 DAS recorded the greatest GP of 84.67 and 83.83%, GI of 299.0 and 293.0; SVI of 1804 and 1779 and fewer fungi incidence (%) of 64.5 and 65.83 respectively. While the greatest GP of 83.83 and 83.00%, GI of 292.8 and 292.17; SVI of 1792 and 1747 and fewer fungi incidence (%) of 64.83 and 65.83 was recorded in seeds stored with SMC of 6% followed by 8% respectively, at 90DAS. Results indicate optimal storage settings (5-20ºC, SMC 6-8%) for maintaining sunflower seed viability and vigor during 90DAS.