Detalle de: Adaptation of avocado cultivation to water and salinity stresses

Avocado (Persea americana Mill.) is a subtropical evergreen tree native to Mesoamerica that belongs to the Lauraceae and that currently is cultivated in more than 50 countries worldwide. Traditionally, avocado genotypes have been classified in three horticultural races or subspecies mainly related to ecological preferences and botanical characteristics: Mexican, Guatemalan and West Indian. The Mexican and Guatemalan subspecies are adapted to highland areas in Central America (cold climates). The West Indian subspecies is adapted to low-land areas in the same region (tropical climates) and shows some salinity tolerance. Most of the avocado varieties cultivated in subtropical and in mediterranean climates are hybrids between the Mexican and Guatemalan subspecies. An example is the variety Hass, which is the most important at the commercial level worldwide, representing about 90% of the Spanish production. Avocado cultivation in Spain and other mediterranean countries has been increasing in the last years due to an exponential increase in demand. However, the most suitable areas models predict that this situation will worsen in the near future. Consequently, it is expected that high quality freshwater supplies will be increasingly scarce in avocado growing regions in the Mediterranean basin and, consequently, there is a need to expand the use of more efficient irrigation practices and adaptation of avocado production to lower quality waters (such as reclaimed wastewater and salinized water). In fact, when water is in short supply, the use of water with increased dissolved solids is often the only option to continue irrigation, that, in the case of avocado in mediterranean climates, is indispensable to guarantee the viability of the crop. In this project, we address this problem using a multi and interdisciplinary approach that covers several fields of knowledge (soil science, plant physiology, breeding and genomics) to understand the changes in soil structure, microbiota and physiological parameters after using lower quality water and reduced water applications together with the development of salinity tolerant avocado rootstocks. For that, we combine the expertise of two complementary research groups from the University of Malaga and the CSIC, with long experience in studies of genomics, physiology, and soil-water-plant interactions in fruit crops, especially avocado. Thus, the main objective of this proposal is to ensure a sustainable production of avocados in continental Europe taking into account the consequences of climate change in the region, mainly reflected in the reduction of freshwater availability for irrigation and the need to use water of lower quality. This main objective is divided into 3 different research lines: (1) monitoring changes at the soil and plant level of using reclaimed wastewater; (2) the evaluation of different irrigations systems that can reduce the water footprint of avocado and (3) the selection of avocado rootstocks more resilient to lower quality irrigation water. This proposal addresses specifically two of the six environmental objectives described in the Regulation (EU) 2020/852 of the European Parliament and of the Council of 18 June 2020 (known as Taxonomy Regulation): adaptation to climate change and sustainable use and protection of water and marine resources.