Influence of anti- and prooxidants on rhizogenesis from hypocotyls of Mesembryanthemum crystallinum L. cultured in vitro

Abstract

The enrichment with antioxidants (glutathione or ascorbate) or prooxidants (alloxan, methylviologen, hydrogen peroxide) of root inducing medium significantly decreased rhizogenesis frequency (alloxan, hydrogen peroxide) or inhibited roots regeneration (ascorbate, methylviologen) during the in vitro culture of Mesembryanthemum crystallinum L. hypocotyls. The adventitious roots morphology, root hairs length and density, was also influenced. Changes in the rhizogenesis course were related to the differences in hydrogen peroxide concentration during following days of culture between explants exhibiting morphogenic potential and those without the ability to form adventitious roots. In explants with morphogenic potential, rhizogenesis induction was always accompanied by a high level of hydrogen peroxide followed by the decrease in H 2 O 2 content in following days. In contrast, in the explants without regeneration potential, the level of hydrogen peroxide was increasing during the culture period. Activity patterns of superoxide dismutase (SOD) and guaiacol peroxidase (POX) in the following days of culture were similar in the explants exhibiting regeneration potential cultured on different media. Total activity of SOD decreased during initial days of culture and then increased due to the activation of additional SOD isoform described as MnSODII. The activity of POX was low during the rhizogenesis induction, and then increased during following days of culture; the increase was correlated with the decrease in hydrogen peroxide content. In the explants without the ability to regenerate roots, the total activity of SOD was low throughout the whole culture period, whereas the POX activity was significantly higher than in hypocotyls with regeneration potential. It might be concluded that the increase in hydrogen peroxide during initial stages of rhizogenesis and the induction of MnSODII are prerequisites for adventitious roots formation from hypocotyls of M. crystallinum, independently in the presence of anti-or prooxidant in the culture medium.

Some Mechanisms Modulating the Root Growth of Various Wheat Species under Osmotic-Stress Conditions

“…The research by Libik-Konieczny et al [59] on rhizogenesis showed the importance of redox balance system for this process, which could be mediated by preventing the negative effects of possible oxidative stress. Isoforms of superoxide dismutase (SOD) and peroxidase (POD) can play a significant role in regulating the content of hydrogen peroxide in the formation of root primordia, as well as in the process of root growth and development [59,60]. The accumulation of ROS in meristematic cells of root tips subjected to stress serves as a signal for autophagy [61].…”

A Culturomics-Based Bacterial Synthetic Community for Improving Resilience towards Arsenic and Heavy Metals in the Nutraceutical Plant Mesembryanthemum crystallinum

“…Seeds of Mesembryanthemum crystallinum (collected at the Guadiamar riverbed) and commercial seeds of Medicago sativa (alfalfa) cv. Aragon were surface disinfected by immersing them in 70% ( v / v ) ethanol for 2 min, followed by immersion in commercial bleach solution (1:2, v / v ) for 10 min, before they were finally washed three times with sterile, distilled water [ 90 ]. Seeds were pregerminated in water agar (9 g∙L −1 ) for 48 h at 25 °C in the dark.…”

Culturomics and Circular Agronomy: Two Sides of the Same Coin for the Design of a Tailored Biofertilizer for the Semi-Halophyte Mesembryanthemum crystallinum

“…Seeds of M. crystallinum (three batches of one hundred seeds each) were surface disinfected by treatment with 70% ethanol (2 min), washing with sterile distilled water, followed by treatment with 2.5% sodium hypochlorite (10 min) with gentle shaking, and finally exhaustive washing with sterile distilled water [78]. Once sterilized, they were deposited on moist sterile perlite in Petri dishes (25 seeds per plate).…”