Stress tolerance in plants via habitat-adapted symbiosis

Abstract

We demonstrate that native grass species from coastal and geothermal habitats require symbiotic fungal endophytes for salt and heat tolerance, respectively. Symbiotically conferred stress tolerance is a habitat-specific phenomenon with geothermal endophytes conferring heat but not salt tolerance, and coastal endophytes conferring salt but not heat tolerance. The same fungal species isolated from plants in habitats devoid of salt or heat stress did not confer these stress tolerances. Moreover, fungal endophytes from agricultural crops conferred disease resistance and not salt or heat tolerance. We define habitat-specific, symbiotically-conferred stress tolerance as habitatadapted symbiosis and hypothesize that it is responsible for the establishment of plants in highstress habitats. The agricultural, coastal and geothermal plant endophytes also colonized tomato (a model eudicot) and conferred disease, salt and heat tolerance, respectively. In addition, the coastal plant endophyte colonized rice (a model monocot) and conferred salt tolerance. These endophytes have a broad host range encompassing both monocots and eudicots. Interestingly, the endophytes also conferred drought tolerance to plants regardless of the habitat of origin. Abiotic stress tolerance correlated either with a decrease in water consumption or reactive oxygen sensitivity/generation but not to increased osmolyte production. The ability of fungal endophytes to confer stress tolerance to plants may provide a novel strategy for mitigating the impacts of global climate change on agricultural and native plant communities.

Fungal Assemblages Associated with Roots of Halophytic and Non-halophytic Plant Species Vary Differentially Along a Salinity Gradient

“…In fact, in adaptive terms, a high prevalence of the fungus is not totally incompatible with a slight parasitism [54]. Alternatively, we could hypothesize that OTU01 gives, in turn, some fitness benefits to its host, as occurs in other similar cases [2,39,53]. Indeed, DSF are often related to beneficial effects on their hosts' development, including nutrient uptake, growth promotion, or tolerance to environmental stresses, although these are frequently difficult to detect [12].…”

Profundae diversitas: the uncharted genetic diversity in a newly studied group of fungal root endophytes

“…As these sites were characterised by small populations (<50 individuals), a relatively open and dry environment, shallow sandy soil and a lack of vegetative competition, then the endophytes may be associated with stress tolerance in the host (Rodriguez et al 2008). Even though the measured site and plant parameters indicated that the plants were growing under at least abiotic stress, most of the plants were in reasonably good health (only three populations were classed as being in poor health, and these were not on the most saline soils) and all had flowered.…”

Antibacterial potential of fungal endophytes isolated from Boerhaavia diffusa L.

“…Endophytic fungi are distributed world-wide and have been isolated from a variety of plant types including mosses, liverworts, ferns and higher plants (Higgins et al, 2007;Rosa et al, 2010;U'Ren et al, 2012). Endophytic fungi have diverse application as they may play role in plant growth (Mucciarelli et al, 2003); plant defense (Gao et al, 2010); affect plant resistance under stressful conditions (both biotic and abiotic stresses) (Marquez et al, 2007;Rodriguez et al, 2008); decompose plant litter (Sun et al, 2011). Apart from these, endophytic fungi are also known to produce many valuable bioactive metabolites including anti-microbial, anti-insect, anticancer, anti-diabetic and immunosuppressant compounds along their great potential applications in agriculture, medicine and food industry (Verma et al, 2009;Zhou et al, 2010;Zhao et al, 2011;Hema et al, 2015).…”