Unraveling the Mitigating Capability of Foliar Application of Potassium Nitrate too Salt Toxicity in Sunflower

Agricultural crops face a major issue in the form of salinity. It causes injuries to plants by causing accumulation of Na+ and Cl- ions, which leads to nutrient imbalance and ultimately low yield. It also causes fluctuations in physiological processes, which destabilize the uptake and distribution of nutrients in crops. Sunflower (Helianthus annuus L.) is the 2nd ranked oilseed crop after soybean. Sunflower possesses high oil content (42-50%) and protein content (15-20%), which makes it one of the most valuable oil crops. Exogenously applied K+ significantly enhance all morphological and physiological parameters. K+ is also member of triad group of nutrients for plants including N and P. In current study effect of foliar application of K at 500 ppm were examined on growth, biochemical and physiological attributes of sunflower hybrid L-16003 grown under saline conditions. Data was recorded for various growth, biochemical and physiological parameters of plants. Analysis of data revealed that salinity adversely affected gas exchange parameters which resulted in reduced growth and yield of sunflower. Exogenous foliar application of K significantly improved gas exchange attributes such as stomatal conductance, CO2 assimilation, transpiration rate and water use efficiency. It also enhanced chlorophyll pigments which resulted in increase of photosynthetic rate ultimately leading to healthy growth of plants grown under saline conditions. Root length, shoot length, plant fresh weight, dry weight and achenes weight were also increased by foliar application of K. Overall, foliar application of K significantly improved all attributes of sunflower and helped to alleviate harmful effects of salinity.