Physiological performance of sunflower genotypes under combined salt and drought stress environment

Abstract

The physiological performance of some sunflower genotypes (S.28111, SF0049, Hysun-33, Hysun-39) under salt, drought stress separately and in combination was examined. Salt, drought and a combination of these stresses were applied to plants by gradual increments. The plants were exposed to stress for two weeks. Relative water content, osmotic potential, stomatal conductance, performance index, dark adapted quantum yield and chlorophyll contents were reduced upon salinity and drought stresses. However, when plants were subjected to a combination of these stresses, a greater reduction in all tested attributes was observed. Proline and carotenoid contents in drought stress were elevated compared to salt stress. Superoxide dismutase (SOD) and catalase (CAT) showed the highest activity in individual salt and drought stress with less accumulation of H2O2. Combined stress reduced the activity of antioxidant enzymes which ultimately decreased the physiological performance of sunflower plants. However, among the tested genotypes, S.28111 and SF0049 were found to be more tolerant to drought, salt and combined stress than both Hysun genotypes. The physiological performance of genotypes against salinity and drought individually and in combination is discussed in detail.

Assessing drought tolerance in field-grown sunflower hybrids by chlorophyll fluorescence kinetics

“…, Performance index (potential) for energy conservation from photons absorbed by PSII to the reduction in PSI end acceptors R and 9444 A × 8129 R). These results are consistent with previous studies' results, in which better performer plants under stress conditions have higher indexes values than others (Oukarroum et al 2007(Oukarroum et al , 2009Boureima et al 2012;Çiçek et al 2015;Umar and Siddiqui 2018). Consequently, tolerant hybrids succeeded to sustain photosynthetic electron transport under drought compared to sensitive hybrids (Fig.…”

Comparative Study of Drought Stress Effects on Traditional and Modern Apple Cultivars

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Sustainable effect of a symbiotic nitrogen‐fixing bacterium Sinorhizobium meliloti on nodulation and photosynthetic traits of four leguminous plants under low moisture stress environment

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