Contrasting responses of cluster roots formation induced by phosphorus and nitrogen supply in Embothrium coccineum populations from different geographical origin

Indexación: Scopus.Aims: Embothrium coccineum is a pioneer tree that produces cluster roots (CR) induced by phosphorus (P) or nitrogen (N) deficiency, but the role which both N and P play in CR formation for different E. coccineum populations is still unknown. We hypothesized that in E. coccineum, N influences the CR formation response, primarily induced by P limitation. However, this response depends on local adaptations to their specific conditions of geographic origin. Methods: Seedlings from three contrasting edaphoclimatic conditions (Northern, Central and Southern populations) were grown in hydroponic culture under high and low N supply and at five different P supply. Morphophysiological responses, including CR number, growth, biomass, P and N plant concentration, were studied. Results: Our results showed that at high N supply, CR formation was stimulated with increased P supply, but just until it reaches a maximum of 5 μM, above this concentration CR formation decreases. However, at low N supply, a constitutive response was observed regardless of P supply. Moreover, each of these responses depends on the populations. Conclusions: Our study suggests that N drives CR formation induced by P supply and that a differential response exists among E. coccineum populations, that could be related to their origin edaphoclimatic conditions. © 2020, Springer Nature Switzerland AG.https://link-springer-com.recursosbiblioteca.unab.cl/article/10.1007%2Fs11104-020-04622-

Molecular characterization of endophytic fungi associated with the roots of Chenopodium quinoa inhabiting the Atacama Desert, Chile

Plant roots can be highly colonized by fungal endophytes. This seems to be of particular importance for the survival of plants inhabiting stressful habitats. This study focused on the Identification of the fungal endophytic community associated with the roots of quinoa plants (Chenopodium quinoa) growing near the salt lakes of the Atacama Desert, Chile. One hundred endophytic fungi were isolated from healthy quinoa roots, and the internal transcribed spacer (ITS) region was sequenced for phylogenetic and taxonomic analysis. The isolates were classified into eleven genera and 21 distinct operational taxonomic units (OTUs). Despite a relatively high diversity of root endophytic fungi associated with quinoa plants, the fungal community was dominated by only the Ascomycota phyla. In addition, the most abundant genera were Penicillium, Phoma and Fusarium, which are common endophytes reported in plant roots. This study shows that roots of C. quinoa harbor a diverse group of endophytic fungi. Potential roles of these fungi in plant host tolerance to stressful conditions are discussed

Effect of nitrogen supply and Rhizobia symbiosis in the isotopic composition of essential plant elements, nutrient content, TCA cycle activity and respiratory energy balance of Lotus japonicus

Resumen de la comunicación oral presentada en: I Spanish-Portuguese Congress on Beneficial Plant-Microbe Interactions (BeMiPlant) and XVIII National Meeting of the Spanish Society of Nitrogen Fixation (XVIII SEFIN). Oeiras, Portugal, 17-19 octubre (2022)This work was supported by FONDECYT No. 1191118 from National Agency for Research and Development (ANID) and the Chilean Scholarship Program/Becas de doctorado nacional/2017–21180329