Effect of Hydro and KNO3 Priming on Seed Germination of Cotton (Gossypium hirsutum L.) Under Gnotobiotic Conditions

Cotton (Gossypium hirsutum L.) is an important cash crop; its germination is very susceptible to salinity. Saline conditions result in a severe decline in yield due to poor germination and seedling establishment. Seed priming is one of the seed pre-soaking techniques which initiates the pre-germination processes in seed embryos by lowering osmotic pressure and leading to uniform germination. We investigated the germination and stand establishment in two cotton genotypes (GH-Baghdadi and GH-Mubarak) under saline conditions by priming with water (Hydro-priming) for 15 h, 20 h, and 25 h durations and interaction of KNO3 (1.25% and 1.5% conc.) with priming durations. The results showed that germination increased significantly in both genotypes at priming treatment with KNO3 for 20 h. Germination index and final germination percentage were higher in GH-Baghdadi compared to GH-Mubarak for the same treatment. Mean germination time was significantly decreased in both genotypes at 20 h priming duration with 1.5% KNO3. Germination rate was significantly higher than control (un-primed) in GH-Mubarak on the combination of 1.5% KNO3 with 20 h priming duration followed by GH-Baghdadi. Cotton genotypes priming with 1.5% KNO3 for 20 h is recommended for synchronized germination and seedling stand establishment under saline environment.