Potassium and calcium enrichment alleviate salinity-induced stress in hydroponically grown endives

Abstract

Tzortzakis N.G., 2010. Potassium and calcium enrichment alleviate salinity-induced stress in hydroponically grown endives. Hort. Sci. (Prague), 37: 155-162.Salinity either of soil or of irrigation water causes disturbance in plant growth and nutrient balance and reduces crop yields. The effects of NaCl salinity and/or calcium or potassium level on the plant growth and severity of gray mold (Botrytis cinerea [De Bary] Whetzel) were investigated in endive (Cichorium endivia L., cv. Green Curled) grown with the nutrient film technique under greenhouse conditions during early spring. Plants were supplied with nutrient solutions containing 40 mmol/l of sodium chloride (NaCl) and/or 10 mmol/l potassium sulphate (K 2 SO 4 ). Additionally, plants treated with foliar spray of 15 mmol/l calcium nitrate [(CaNO 3 ) 2 ] or distilled water. Salinity or K-and Ca-enrichment mainly affected the upper part of endive plants and reduced leaf area. However, when salinity combined with either K-or Ca-enrichment, the negative impact of salinity on plant growth was reversed. Salinized and/or K-and Ca-enriched, plants did not differ in plant biomass, leaf/root ratio, leaf fresh weight, leaf number, and root length. Salinity did not have any impacts on photosynthetic rate, stomatal conductance, and intercellular CO 2 concentration. Indeed, photosynthetic rate and stomatal conductance increased with Ca foliar application and decreased with K while the opposite effects were observed for the intercellular CO 2 concentration. Total nutrient uptake was reduced 2-fold in salt-treated plants compared to controls. No symptoms of tip-burn or blackheart were recorded throughout the experimental study. Endive grown in the nutrient film technique had tolerance to NaCl salinity, and this method could be used to exploit saline water in soilless culture. These findings also suggest that a proper management of the salt concentration of the nutrient solution plus external elemental enrichment may provide an efficient tool to improve the quality of leafy vegetables with little effect on yield.

Alleviation of Salt Stress by K2so4 in Two Wheat (Triticum Aestivum L.) Cultivars

“…1a). Similar results have been reported by Tzortzakis (2010) and Ashraf et al (2013), who showed that application of potash fertilizer decreases the toxic effects of salinity on growth, as well as plant biochemical and physiological processes.…”

“…They showed that N and K + contents decrease in stressed environment and with the application of nutrients like potassium, the uptake of essential nutrients i.e., Ca 2+ , K + and Mg 2+ can increase followed by proper regulation of all metabolic activities, and resulting in an improvement of growth and productivity. Tzortzakis (2010) and Ashraf et al (2015) also state that K + is a vital nutrient and growth of plants depends upon its availability. Both wheat cultivars showed positive response to K 2 SO 4 and absorption of potassium nutrients (Fig.…”

Effect of Potassium Sulphate on the Growth and Uptake of Nutrients in Wheat (Triticum aestivum L.) Under Salt Stressed Conditions

“…8; effect of salt stress was alleviated on the lengths of roots. Same was reported by Ashraf et al (2013) and Tzortzakis (2010) that supplementary potassium reduced the effects of salt stress on the growth of plants (Wang et al, 2013).…”

“…Similar findings are also depicted by that salt stress negatively effect the plant growth and development in such a way that many metabolic processes bcomes hinders because of nitrogen deficiency in plants. It is also reported that potassium is essential nutrients and growth of plants increased in the potassium fertilizer and there is more absorption of nitrogen contents by the use of fertilizer as investigated by Tzortzakis (2010) and Ashraf et al (2013).…”

“…Several reports are available in agreement of the present studies that fresh biomass production reduced by the salinity stress as compared to non saline conditions (Kausar et al, 2012;Akhtar et al, 2013;Kausar & Gull, 2014). However use of fertilizers in stressed conditions proved better for the high biomass production of crops Tzortzakis, 2010).…”