Sunflower Seed-priming with Phosphate Salts and Seedling Growth under Salt Stress

Aims: It was assumed that halo-priming process under salinity stress may rely on phosphorus nutrient source. Nutrient priming of seeds of sunflower seeds may be beneficial for growth of seedlings under salt stress.

Study Design: Laid out the experiment in Complete Randomized Design, using NaCl @ 0, 15, 30, 45 and 60 mM on prime seeds from two sources of phosphorus salts in quadruplication.

Place and Duration of Study: The study was conducted in laboratory of Soil Salinity Research Programme of Land Resources Research Institute at National Agricultural research Centre, Islamabad, Pakistan during the period from July to September, 2016.

Methodology: Passed sunflower seeds through the priming process using two sources of phosphorus i.e. potassium dihydrogen phosphate (KDP) and ammonium dihydrogen phosphate (ADP). The seeds were then germinated and raised for seedlings establishment in hydroponics standard solution under salt stress (0, 15, 30, 45 and 60 mM sodium chloride).

Results: The germination parameters, i.e. germination percentage, mean germination time, rate of germination index and coefficient of germination improved significantly (P< 0.01) with KDP priming than that of ADP under salinity stress. Seedlings vigor index enhanced with KDP than ADP. Fresh mass (18 to 36 percent) and dry mass (14 to 24 percent) of the seedlings were higher with KDP. With increasing Na+, Ca2+ decreased. It was inferred that role of KDP source was prominent.

Conclusion: Consideration of KDP could be a valuable seed-priming approach for sunflower early germination and accelerative growth under salt stress.