LegumBiome-Drought Project: Screening of potential plant drought-tolerance enhancers of wild, desert-adapted legumes
Creators: name: Castro, Marla Niza
name: Dias, Eva
name: Millia McQuade
name: Joao Carilho
name: De Jesus, Horacio Manue Mixao
name: Vilchez, Juan Ignacio
Publisher: name: Zenodo
Year: 2022
Subjects: Wild legumes
Drought-adapted microbiota
Seedborne microbiota
Bioinoculation
Medicago sativa
Bituminaria bituminosa
Anthyllis sp.

description: Agriculture is at the gates of a new and necessary revolution. The pressure caused by the depletion of the soil, as well as by the increasingly harsh climatic conditions, are leading to the search for alternatives for fertilization and improvement of cultivation methods. In this scenario, the microbiota is playing a very relevant role. Since the mid-1970s, the enormous potential of using microorganisms as fertilizers, stress tolerance enhancers or as pest and pathogen biocontroller, has been frequently reported. However, it has been more recently when, through the use of massive sequencing techniques and precision analysis, we have been able to generate complex networks of these beneficial interactions. Microbial diversity has provided with very valuable information regarding what species, population relevance or changes occur throughout ecosystem dynamics. This opens the door to the use of bioengineering techniques to improve soil health, microbial biodiversity or patterns of interactions. Among them, the use of root exudates to anticipate the presence of beneficial microbial communities, the composition of synthetic communities (SynComs) or the shaping of agricultural soil communities by implementing the transfer of stress-adapted beneficial microbes stand out. In this context, we will introduce the results of work on the stress-root exudate-recruitment relationship, and the use of drought-adapted wild legume microbiota as part of the LegumBiome project, as case studies.<br> In this last work, we aim to describe the cultivable communities associated with wild legumes, adapted to desert conditions, with the aim of characterizing candidate strains to improve the response of plants to drought. To do this, we are carrying out sampling in different parts of the Eastern Spain, corresponding with those regions reported as under risk of desertification, including Navarra, Huesca, Zaragoza, Soria, Madrid, Albacete, Jaén, Granada, Almería, Murcia and Alacant. Collected samples included rhizosphere soil, roots, nodules and seeds from herbaceous and shrubby species alive during the summer months. Culturable strains from these samples were identified and characterized based on their xerotolerance, production of phytohormones related to drought response, and colonization skills. Those with the best results are being tested on commercial crop legumes (Phaseolus vulgaris, Len culinaris, Cicer arietinum) to assess their drought-tolerance enhancement, as well as their production rate under such conditions. So far, we have isolated more than 400 strains from up to 25 different plant species. Among them, about 20 strains have shown to be effective to enhance the response of plants to drought. The molecular and metabolomic characterization of these interactions will allow us to better understand the mechanisms used, as well as the possibility of using such strains as bioinoculants capable of improving crop yields under more severe conditions of water deficit.<br>