Lucas Gabriel Castellani

Constant increase in world population requires new approaches for enhancing food production. In agriculture, development of crops resistant to stress conditions could lead to increased yields. Understanding mechanisms of plant stress adaptation is a key step to achieve this goal. ln recent years, extrachromosomal circular DNA (eccDNA) has emerged as a new mechanism regulating genome plasticity in eurkaryots. In plants in particular, this field remains little explored, with few works describing the presence of eccDNA as a potential new mechanism for plants to respond and adapt to biotic or abiotic stresses. Nevertheless, there is no information yet about the presence and function of these molecules in legume plants. Considering the environmental and economic importance of legume crops across Europe, being a key element for sustainable agricultural systems, this work aims to investigate the possible involvement of eccDNA in the response to drought of legume plants. Specifically, we propose a strategy to detect, isolate and sequence eccDNA from different tissues of a model plant, Medicago truncatula, closely related to alfalfa, the second most cultivated legume in Europe. The comparison between the eccDNAs produced under drought conditions of three M. truncatula cultivars with differential tolerance to drought stress could allow the identification of mechanisms for drought resistance such as specific gene amplification. Moreover, the project will include the analysis of eccDNAs in presence of the effective symbiont Ensifer meliloti, to understand if differences in nitrogen biological fixation under different conditions could be related to the information encoded in eccDNAs. Altogether, this project will provide new information on how eccDNAs are related to the mechanisms that contribute to drought resistance in legumes and possibly reveal new pathways to obtain better adaptative and more productive crops.

Environmental agrobiology workshop. Participation in a presentation for PhD students from Public University of Navarre (UPNA) and University of the Basque Country (UPV/EHU).

Abstract submitted to European Nitrogen Fixation Conference 2023 (ENFC). “Is ethylene signaling required for drought stress responses in Medicago truncatula?” Authors: Rocío Abín, María I. Rubia, Lucas G. Castellani, Ángel M. Zamarreño, José M. García-Mina, Cesar Arrese-Igor, Estíbaliz Larrainzar