Epsilon Archive for Student Projects

Abstract

Plants are exposed to various environmental stress conditions, to which they must adjust accordingly. These responses are tightly regulated by molecular signalling pathways. Plants are generally exposed to multiple stressors at once and signalling molecules can share a substantial overlap. Cross-talk between stress signalling pathways can result in cross-tolerance, in which exposure to one stress increases tolerance to subsequent exposure of another type of stress. Growing evidence suggests that abiotic stress might influence regeneration potential in Arabidopsis thaliana. Yet, it is unknown whether this effect is conserved in other Arabidopsis ecotypes, species and in different types of regeneration processes.

Therefore, our study aimed to investigate whether abiotic stress treatment affects the regenerative ability across three types of regeneration processes; wound-induced callus, hormone-induced callus and grafting. In addition, we also explored the effects in three different plant species and five Arabidopsis ecotypes having variant inherent stress tolerance and regenerative capacities. We observed that the treatment enhanced the wound-induced callus formation in all Arabidopsis ecotypes examined. However, the optimal amount of stress treatment varied between accessions. Further experiments in Solanaceae indicated that stress-treated aubergine and tomato cotyledons exhibited increased callus area when placed on media containing exogenous hormones. Grafting success of stress-treated Col-0 seedlings was reduced compared with control, while in aubergine and tomato there seemingly is no difference.

Taken together, our results indicate that treatment of abiotic stress can positively influence regenerative responses in plants and that these effects vary between species and accessions. Further studies are required to elucidate the mechanistic link between abiotic stress and regeneration.