Getting ready for the ozone battle: Vertically transmitted fungal endophytes have transgenerational positive effects in plants

Abstract

Ground-level ozone is a global air pollutant with high toxicity and represents a threat to plants and microorganisms. Although beneficial microorganisms can improve host performance, their role in connecting environmentally induced maternal plant phenotypes to progeny (transgenerational effects [TGE]) is unknown. We evaluated fungal endophyte-mediated consequences of maternal plant exposure to ozone on performance of the progeny under contrasting scenarios of the same factor (high and low) at two stages: seedling and young plant. With no variation in biomass, maternal ozone-induced oxidative damage in the progeny that was lower in endophytesymbiotic plants. This correlated with an endophyte-mediated higher concentration of proline, a defence compound associated with stress control. Interestingly, ozoneinduced TGE was not associated with reductions in plant survival. On the contrary, there was an overall positive effect on seedling survival in the presence of endophytes. The positive effect of maternal ozone increasing young plant survival was irrespective of symbiosis and only expressed under high ozone condition. Our study shows that hereditary microorganisms can modulate the capacity of plants to transgenerationally adjust progeny phenotype to atmospheric change.

Ethylenediurea (EDU) spray effects on willows (Salix sachalinensis F. Schmid) grown in ambient or ozone-enriched air: implications for renewable biomass production

“…For example, young leaves in this willow may act as a sink of Mg and carbon after activation of STAY-GREEN gene encoding Mg-dechelatase enzyme that catalyzes the reaction of extracting Mg from chlorophyll to synthesize phaeophytin (Shimoda et al 2016;Sato et al 2018). Whether root-or leaves-associated microorganisms (e.g., endophytes; Ueno et al 2020Ueno et al , 2021 are involved in these mechanisms remains unknown and warrants further studies. Across all treatments, Mg was positively associated with Fe and Ni, and negatively associated with K and Cr in fallen leaves, suggesting that the effect of EOZ on Mg can be driven by changes in Fe, Ni, K, and Cr.…”

Plant stress responses compromise mutualisms with Epichloë endophytes

“…Epichloë can also enhance antioxidant levels that generally increase the fitness of symbiotic plants under stressors that increase ROS-associated oxidative damage ( Fig. 1 ) ( Ueno et al ., 2021b ). Under water deficit, the biomass of Elymus dahuricus plants was increased by the presence of endophytes that enhanced contents/activities of several antioxidants that reduced the oxidative damage within plant tissues ( Zhang and Nan, 2007 ).…”