Growth, yield and ionic concentration of two sunflower (Helianthus annuus L.) genotypes exposed to brackish water irrigation

The effects of brackish water application were assessed on the growth, uptake of sodium (Na^+), potassium (K^+), water relations, membrane stability index, proline accumulation, and yield of two sunflower genotypes (SF-187 and hysun- 33). Treatments of irrigation water with different ECiw, SAR and RSC were T1, control; T2, EC: 8 dS m^-1; T3, SAR: 16 (mmol L^-1)^1/2; T4, RSC: 4 meq L^-1, and T5, EC: 8 dS m^-1 + SAR 16 (mmol L^-1)^1/2 + RSC 4 meq L^-1. Genotypes displayed a substantial variability for salinity and/or sodicity tolerance and salt tolerant behavior of SF-187 regarding, high K:Na ratio, increased water contents, higher membrane stability index and higher yield as compared to Hysun-33, was confirmed under various treatments. Saline-sodic water caused maximum reduction in plant growth and yield in both sunflower genotypes followed by saline water treatment. However, no significant differences were noted between high SAR (T3) and high RSC (T4) treatments. In conclusion, SF-187 exhibited some important features of salt tolerance that can be successfully exploited under brackish water irrigation.