NaCl and Na2SO4 Salinities Have Different Impact on Photosynthesis and Yield-Related Parameters in Rice (Oryza sativa L.)

Abstract

To elucidate the comparative effect of chloride and sulfate salinities on photosynthesis and yield components in rice, plants of Oryza sativa (cv. I Kong Pao (salt-sensitive)) were exposed in nutrient solutions to 20 mM Na2SO4 or 40 mM NaCl (electrical conductivity of c.a. 4.30 dS m−1 for both solutions) from seedlings to maturity stage. Both types of salt induced a strong decrease in net photosynthesis (AN) at the seedling and tillering stages, while the intercellular CO2 concentrations (Ci) remained unaffected. Instantaneous transpiration (E) and stomatal conductance (gs) decreased at the tillering and seedling stages, respectively, only in plants exposed to NaCl. Chloride salinity also strongly decreased photosynthetic pigments, while no impact was detected in response to Na2SO4. All yield-related parameters were affected by salinities, but NaCl was significantly more deleterious than Na2SO4 for the mean number of tillers produced per plant, spikelets sterility and non-viable pollen percentage. In contrast, both types of salinity similarly impacted the percentage of fertile tillers and 1000-grain weight. At the grain level, more than 90% of toxic ions (Na+, excess of Cl− and S6+) accumulated in the hulls, thus preserving the internal part of the caryopses from toxic ion injuries.

Effect of NaCl stress on tillering of rice (Oryza sativa L.) and mitigation regulation of prohexadione-calcium

“…In contrast, Ls was signi cantly higher than that of the control (Fig. 4-7), which is consistent with the results of previous studies [43][44][45] . The decrease of Ci and the increase of Li and the simultaneous decrease of Pn and Gs are thought to lead to the decrease of photosynthetic rate through stomatal limitation 46,47 , which because salt stress causes physiological drought in plants.…”

Elucidating morpho‐anatomical, physio‐biochemical and molecular mechanism imparting salinity tolerance in oats (Avena sativa)

“…Seeds of all 20 oat genotypes were germinated in hydroponics using Hoagland nutrient solution (Hoagland & Arnon, 1938) with seven different salinity levels. Since, actual field salinity is resultant of accumulation of various salt ions mixture (Bai et al, 2018;Irakoze et al 2020;Vargas et al 2018), therefore to mimic saline field condition in pots and hydroponic media, we used mixture of NaCl and Na 2 SO 4 in our study. Both NaCl and Na 2 SO 4 salts were mixed in equimolar ratio in such a way that the resultant solutions were of 0, 60, 80, 100, 120, 140 and 160 mM concentrations.…”

Ions and Organic Solutes as Implicated in the Ameliorative Effect of Exogenous Application of Calcium on Salt Stressed Tomato (Lycopersicon esculentum Mill.) Plants

“…It is considered as the major abiotic factor that limits plant productivity and agricultural yield [1,2]. Several studies have reported that salts present in soil and in irrigation water reduce plant growth [3][4][5][6][7][8][9][10] and consequently reduce crop production. Soil salinity affects plant growth, either through osmotic effects or ionic toxicity effects.…”