Interaction of Salinity and Phytohormones on Wheat Photosynthetic Traits and Membrane Stability

Abstract

To evaluate phytohormones effects on stomatal conductance, chlorophyll fluorescence, membrane stability, relative water content and chlorophyll content under salinity, a factorial experiment with 4 replicates was conducted. Treatments were salinity (0, 3.5 and 7 dS/m), phytohormones (control, gibberellic acid and abscisic acid) and wheat cultivars (Gascogen, Zagros, and Kuhdasht). Results showed that a high level of salinity increased chlorophyll fluorescence and relative water content, while membrane stability, chlorophyll content, and stomatal conductance were decreased. Abscisic acid treatment had more effective role in membrane stability. Although membrane stability was much more under gibberellic acid treatment, restoration of membrane stability was considerable under abscisic acid treatment for Gascogen and Kuhdasht cultivars. Spraying of gibberellic acid induced the highest chlorophyll content in the three salinity levels and all of the cultivars. The maximum amount of stomatal conductance was achieved under gibberellic acid treatment. Abscisic acid caused less chlorophyll fluorescence in comparison to gibberellic acid. About relative water content, abscisic acid was effective in high salinity levels so that it caused stomatal closure, which reduced water loss and maintained turgor in plants.

Investigation of seed germination indices for early selection of salinity tolerant genotypes: a case study in wheat

“…Comparison of tolerance to salinity stress across the genotypes with their corresponding control showed that Zagros had the least rate of decrease in membrane stability at 7 dS m -1 salinity. Moreover, genotypes with higher tolerance had the highest stomatal conductance, which is an indicator for stress tolerance (Pazuki et al, 2013). In the present investigation, we observed that Zagros is the most tolerant genotype and Gascogen is the least tolerant one, which is in agreement with our previous publications.…”

“…Previously, we had investigated the effects of salinity on mature wheat, where we recorded some physiological parameters for the most tolerant and susceptible genotypes to the stress (Aflaki Manjili et al, 2012;Pazuki et al, 2013). In the present research, we have studied effects of the same levels of salinity on the previously used three wheat genotypes affected by two levels of salinity in comparison with distilled water (control).…”

Responses of Water and Pigments Status, Dry Matter Partitioning, Seed Production, and Traits of Yield and Quality to Foliar Application of GA3 in Mungbean (Vigna radiata L.)

“…However, foliar application of GA 3 at 200 ppm produced the highest amount of chlorophyll a, chlorophyll b, and carotenoids which were statistically similar to 300 ppm of GA 3 . These results are supported by several studies reporting that GA 3 enhanced the photosynthetic pigments in V. radiata (Mubeen et al, 2014;Baliah et al, 2018;El Karamany et al, 2019) as well as other crops like wheat (Pazuki et al, 2013), cotton (Onanuga et al, 2012;Firmino da Costa et al, 2017), Euphorbia lathyris (Garg and Kumar, 2012), Aloe barbadensis Data are presented as mean ± SE (n = 3). Data followed by same letter are not significantly different by DMRT test at p < 0.05, CV, Co-efficient of variation.…”

Improvement of Salt Tolerance in Durum Wheat (Triticum Durum Desf.) by Auxin and Kenitin Application

“…This may be due to the inhibition of pigment degradation or stimulation of protochlorophyll (ide) synthesis by phytohormones. In sum, phytohormones play a significant role in moderating the effects of salinity on photosynthetic traits and membrane stability (Pazuki et al, 2013). …”