Chemical Seed Priming with Zinc Sulfate Improves Quinoa Tolerance to Salinity at Germination Stage

Abstract

This study was conducted to assess the effect of seed pre-treatment “priming” with zinc sulfate (ZnSO4) on the improvement in germination in three quinoa genotypes, “ICBA-Q5”, “Puno” and “Titicaca”, under different salinity levels and to characterize some physiological traits of seed tolerance to salinity. The germination tests were conducted to assess the priming effect on germination. Samples of 50 quinoa seeds of the 3 genotypes were soaked in 1 g/L of ZnSO4 solution for 8 h and then were dried under ambient temperature. Then, each seed sample was placed in a Petri dish containing filter paper imbibed with a salt solution of 300, 400 and 500 mM NaCl. The numbers of germinated seeds were noted every 24 h and seed samples were collected for reserve mobilization analysis. The results showed that, under control conditions, ICBCA-Q5 showed the highest germination percentage, followed by Puno and then Titicaca. The salinity level of 300 and 400 mM NaCl severely inhibited the seed germination in all of the tested genotypes and the concentration of 400 mM NaCl was considered the highest threshold for germination in the quinoa genotypes tested. The priming treatment improved the germination parameters and the improvement was more evident for germination speed and the final germination percentages that were generally increased by ZnSO4 priming by more than 100% for all of the genotypes.

Keywords

• priming
• quinoa
• salinity
• germination
• zinc sulfate