Lettuce Response to Leachate Recycling in an Arid Zone Greenhouse

Abstract

Lettuce response to salinity has been studied in open irrigation systems but not under solution recycling conditions. The objective of this study was to determine effects of threshold EC values for solution replacement on stalk weight and quality, solution chemistry and quantities of water and nitrogen removed from the system. Results showed that lettuce yield response to threshold EC in recycled solutions was similar to response to steady salinity in open irrigation systems reported in the literature. The salinity induced yield decline was stronger in the spring than in the autumn growing season. Accumulated NaCl in solution reduced Mg, Ca and K concentration in leaves in the spring experiment, but only Mg was significantly correlated with untrimmed and trimmed stalk yield. Recirculation reduced water and nutrients discharge and hence their input into the system. Increasing the threshold EC from 2 to 4-5 dS/m reduced water discharges by 60-to-100%, while the yield decline was ~10% in autumn and ~20% in spring.

Pseudomonas stutzeri and Kushneria marisflavi Alleviate Salinity Stress-Associated Damages in Barley, Lettuce, and Sunflower

“…The opposite results were obtained by Ahmed et al (2019) , who observed a gradual reduction in the water content in L. sativa roots and shoots with increasing NaCl concentration (2019). Many differences in the growth parameters of L. sativa grown under salt stress have been observed by various researchers (e.g., Bar-Yosef et al, 2005 ; Ünlükara et al, 2008 ; Kurunc, 2021 ). Presumably, the varieties of L. sativa are characterized by large differences in salinity tolerance, and plant responses may be related to other morphological and physiological parameters.…”

Overview of a Lab-scale Pilot Plant for Studying Baby Leaf Vegetables Grown in Soilless Culture

“…In a few articles detailed indications are given on the technical preparation and management of an experiment in SCS (Karam and Al-Daood, 2005;Marfà et al, 2005;Rouphael et al, 2005), but little information is available about the description of the experimental sizing (Frezza et al, 2005;Huber et al, 2005;Sato, 2005;Thompson et al, 1998). Only a few authors such as López-Galarza et al (2005) report indication about the suppliers, and some articles have details of the system also with the graphic scheme (Bar-Yosef et al, 2005;Karam and Al-Daood, 2005;Marfà et al, 2005).…”