Salinity-driven oxidative stress in Gerbera jamesonii cv. Bolus

Abstract

Salinity adversely affects various plants’ metabolic processes, negatively influencing their productivity and crop yield. Gerbera jamesonii cv. Bolus is a commercially important ornamental plant cultivated globally throughout the year for its cut flower production in polyhouses. During polyhouse cultivation, repeated fertigation may cause salinity in Gerbera, affecting flower quality and yield, and functional alterations in the basal level of cellular antioxidative defence systems. Though several factors induce salinity in general, we focussed on NaCl as it is one of the major components of fertigation. In salt-stressed plants, monitoring altered levels of antioxidative defense systems may help better understand their physiological changes. However, little to no studies were attempted on salinity-induced oxidative damage in Gerbera till date. In the current study, we verified the salt sensitivity level of Gerbera with varying concentrations of NaCl (0-200 mM) using in vitro leaf disc approach. We measured various antioxidative enzymatic/non enzymatic defense systems besides MDA and chlorophyll content. Treatment with higher salt concentrations (above100 mM NaCl) exhibited severe bleaching in leaf discs, followed by elevated levels of H2O2, lipid peroxidation and proline. Besides, our study also revealed a decrease in the total chlorophyll content; activities of superoxide dismutase, catalase, glutathione reductase, and ascorbate peroxidase. The observed results showed that Gerbera might not tolerate higher levels of NaCl as it could be detrimental to its cellular activities. Future studies on decoding molecular networks associated with salinity stress and antioxidative defense systems may help in developing salt-tolerant varieties in Gerbera and several other ornamental plants of Asteraceae.

Ascorbic acid mediated Salt Tolerance in Gerbera jamesonii: A Promising Strategy for Sustainable Floriculture

“…The observations and data depicted in the figures and graphs are the mean average of the results revealed from five experiment groups that were performed in triplicate at different time intervals. Using Sigma plot software version 12.0, the data were exposed to a number of statistical parameters (mean, standard error, and one-way ANOVA) in order to establish the significance using the Holm-Sidak method as per Uzma et al [3,4,5].…”

“…The molar extension coefficient (36 M -1 cm -1 ) of the decrease in substrate (H2O2) concentration during the course of three minutes was calculated. Molecules of µmoles of H2O2 reduced (min -1 mg -1 protein) were used to express the CAT activity by Uzma et al 2022b [4]. 4.8.2.…”

“…Molecules of µmoles of H2O2 reduced (min -1 mg -1 protein) were used to express the CAT activity by Uzma et al 2022b [4]. 4.8.2. The assay for determining Ascorbate Peroxidase (APX) activity APX activity was assayed employing the protocol of Nakano and Asada (1981), with a few changes.…”

“…In view of the above, Gerbera growers prefer polyhouses which offer controlled conditions for sustainable production. Despite the high yields that poly house cultivation offers, frequent fertigation practices may cause a reduction in growth and productivity after three years of plantation because of salt build-up on the soil's surface, making it saline [4]. 2 Salinity not only impairs Gerbera's ability to absorb water but also shows drastic effects on the growth of Gerbera [5].…”

Insights into the impact of spermidine in reducing salinity stress in Gerbera jamesonii

“…Although G. jamesonii is grown in green/polyhouses under controlled conditions pertaining to its susceptibility to inconsistent environmental conditions, it gets prone to salinity stress over a period of time [8]. Greenhouse grown G. jamesonii are subjected to regular fertigation with inorganic chemicals and fertilizers which accumulate on the upper layers of soil bed forcing plants to absorb more salts through their roots resulting in salinity [9]. Salinity, a major abiotic stress, restricts a plant from attaining its maximum productivity.…”