Due to the great influence of agrochemicals, biotic and abiotic stresses in the era of climate change dramatically affect soil health. The stress caused by drought has a negative impact on crop yields, often leading to food shortages. Plants have complex metabolic systems that can withstand drought, but their abilities do not always allow them to successfully cope with external factors. The introduction of environmentally friendly external additives can significantly increase the growth and productivity of drought-resistant plants.

The staff of the D.I. Ivanovsky Academy of Biology and Biotechnology of the Southern Federal University, including the leading researcher Vishnu D. Rajput, is working to solve this problem. According to him, the microbiome of soil and plants has significant potential to serve as a major component of food security by reducing the harmful effects caused by drought. In a recent study, the results of which are published in the journal Environmental Geochemistry and Health, Vishnu revealed that the rhizosphere microbiome (root microbiome; a dynamic community of microorganisms associated with plant roots) changes the "rules of the game" on the way to restoring the functioning of the soil, regulating the nutrient cycle, decomposing organic matter, determining the structure of the soil, suppressing plant stresses and maintaining their productivity. The addition of microbes and bio-carbon improved soil properties and increased the availability of nutrients for plants to digest.

Previously, the team of scientists had already produced various types of biochar in laboratory and model experiments. This time they investigated the benefits of biochar in the soil system. Due to its porous structure, biochar provides a habitat for microbes and creates nutrients for their functioning. The idea is to use biochar to enhance the functionality of rhizosphere microbes, which will improve the biological and chemical properties of the soil.

This work was prepared by the team of the SFedU International Laboratory of Nanobiotechnology together with Indian colleagues (Veer Bahader Singh Pervanchal University). As part of it, scientists were engaged in editing the CRISPR/Cas9 genome [approx. a new technology for editing the genomes of higher organisms based on the bacterial immune system]. Based on experience in the genetic editing of microbes, as evidenced, for example, by a metagenomic study of various types of soils, which were compared with the microbial community of the reserved virgin land in collaboration with the Pushchina Institute of Microbiology, in this project, scientists at the Southern Federal University used the shotgun sequencing method. It involves randomly splitting the genome into small fragments of DNA that are sequenced individually. It is this method that the researchers plan to develop on the basis of the laboratory and are already implementing in their research projects. Thus, using this method, it became possible to edit the genomes of rhizosphere microbes to improve their properties and sustainable development in drought conditions. This is important because such microbial communities are extremely important for improving soil health and fertility.

"Our group effectively works with various types of bio-carbon: bio-carbon composites with nanomaterials and bio-carbon integrated with effective microbes. In this work, we use biochar to enhance the functionality of the soil rhizosphere microbiome, microbes that are closer to the root zone of plants. The activation of these microbes in the root zones increased the availability of essential elements for plants, which led to improved plant growth. This is a bioengineered approach to the sustainable development of the rhizosphere microbiome. We have already found out that biocarbon, including nanobiocarbon, provides a better habitat for microbial functionality and colony development," said Vishnu D. Rajput.

A consortium of rhizobacteria and mycorrhizal fungi that stimulate plant growth in biochar can be applied directly to the soil, since the use of biochar reduces the number of effects of climate change. The main advantage of this technology is that biochar uses biomass in such a way that carbon is retained and stored, as opposed to direct combustion. The success of this technology depends on various environmental factors, the degree of drought and temperatures, climatic conditions and soil types, as well as vegetation and fertilizer application. Nevertheless, a consortium of microbes integrated into the biochar can be applied at the field level with the greatest efficiency and productivity.

The development of advanced scientific approaches, technologies and strategies for soil protection and restoration is an important task of the SFedU strategy within the framework of the Priority 2030 Program (national project "Science and Universities"). These studies are conducted within the framework of the SFedU project "Soil Resource Management and Agro-climatology".