"Innovative Biotechnology for Enhancing Plant Tolerance to Root-Knot Nematodes"

Abstract :

"Root-knot nematodes (RKNs) are widespread in Brazil's agricultural regions. Due to their adaptability and broad host range, they pose a threat to productivity. Integrated management, particularly the use of resistant cultivars, is the most effective and sustainable approach, given the limitations of chemical control in terms of cost and environmental impact. New biotechnological tools based on transgenesis (RNA interference and gene overexpression) or genome editing are powerful strategies that can be used in the development of tolerant cultivars. An important step in this process is the exploration and validation of new molecules (e.g., genes and promoter sequences) associated with plant resistance or susceptibility to RKNs. Previous genome and omics studies of our research team, in collaboration with INRAe, allowed us to identify some potential soybean genes associated with susceptibility or tolerance to Meloidogyne incognita. In parallel, we also explored putative M. incognita genes that code for effector molecules which are essential for nematode infection. Our main challenge is transforming this substantial and valuable quantity of knowledge into practical solutions for plant breeding. To that end, we developed an ex vitro hairy root system for a fast in planta screening of target molecules during soybean parasitism by RKNs. Thus far, we have tested and validated more than 15 molecules. The most promising were used for the stable transformation of Brazilian soybean cultivars. This system also allowed us to improve genome editing techniques and explore new CRISPR approaches to knock out and overexpress genes. Our goal is to obtain plants that can be considered non-transgenic, which would reduce the time and cost of commercial release of new biotech cultivars. This integrated pipeline—from the identification of candidate molecules to functional validation and plant transformation—provides a robust framework to accelerate the development of soybean cultivars with enhanced tolerance to RKNs."