Andrés Bello University academic and iBio researcher studies the initial moments when plants face drought

In its second year of research within the framework of a regular Fondecyt project, progress has been made in understanding the early stages of how plants sense the lack of water and which genes regulate adaptation to drought.

By Lorenzo Palma Morales, Science in Chile.- The challenge is to find mechanisms that allow plants to resist drought, but without stopping growing, says researcher José Alvarez, who leads the Fondecyt research financed by the National Research and Development Agency (ANID) and associated with the Millennium Institute of Integrative Biology iBio.

The academic belonging to the Center for Plant Biotechnology (CBV) of the Andrés Bello University, explains that they have managed to identify early plant responses to drought and are making progress in identifying the regulatory genes involved. Interestingly, they have found that the response of genes to drought can precede rapid physiological changes known as stomatal closure. The stomata are true pores that allow the exchange of carbon dioxide (CO_two) and water. Once the plant perceives the drought, the stomata close to prevent excessive water loss. Identifying genes whose response precedes this process will be relevant to intervene in the initial stage of adaptation.

To date, it has been well studied how the hormone absicic acid (ABA) contributes to the adaptation of plants to drought. One of the main functions of this plant hormone is to mediate the closure of the stomata.

However, by closing the stomata, CO uptake is also prevented._two necessary for photosynthesis, and therefore plant growth is affected. Discovering adaptation mechanisms independent of ABA, which until now are little known, will eventually serve to generate plants that resist drought and, at the same time, grow larger and are more productive.

The UNAB researcher says that they have evaluated how plants cope with drought in a period of 0 to 10 days to distinguish between ABA-dependent and ABA-independent mechanisms. In this period, they seek to identify genes of early expression that can regulate the concomitant adaptation of the plant to the lack of water.

Dr. Alvarez’s team is using the model plant Arabidopsis thaliana, but in a parallel way, analyzes are being carried out with rice, tomato and corn, due to their importance for food security.

“The response of plants to drought – at the level of gene regulation – happens quickly, is dynamic and begins long before the plant is visibly affected by the lack of water resources.

In order to respond and adapt to drought, plants must sense the lack of water in a timely manner. It is therefore important to understand the processes that occur at the beginning to design strategies that allow the generation of plants that are more adaptable to this adverse scenario”, said the doctor in Biological Sciences with mention in molecular genetics and microbiology.

Some relevant research questions are: which genes are activated first? Which genes are regulated independently of ABA? Which genes whose behavior help us to predict physiological responses? These are the questions raised in the research that ends in 2024 and, with this, a better understanding will be obtained of how plants dynamically sense drought in order to adapt to this phenomenon, which is predicted to be more intense in years to come.

Dr. Alvarez and the researchers in his team use computational strategies, integration of genomic data, and experimental validations to understand how genes are regulated in plants.

By integrating different layers of information, it will be possible to know which are the most important regulators in a drought event and which are the common processes in different plant species. This information will be relevant to face the effects of climate change on different crops of national and global importance.