Secondary Metabolites as Biomarkers in Breeding for Biotic and Abiotic Stresses in Plants

Abstract

Understanding the relationships between metabolite profiles and plant responses to various environmental stresses is a major goal in plant breeding. However, linking molecular markers patterns of plants to environmental pressures and trait variation remains difficult due to ecological driven plasticity. Integrating metabolite profiles as biomarkers alongside molecular markers presents an opportunity to address this challenge. Plants mitigate various biotic and abiotic stresses by activating multiple protective mechanisms. The diversity of secondary metabolites, shaped by environmental selection pressures, plays a critical role in these adaptive responses. Despite their significance, current functional classification systems for plant metabolites remain limited. A more comprehensive understanding of secondary metabolites as integrated components of metabolic networks, shaped by dynamic environmental pressures, can provide insights into plant metabolism and plant-environment interactions across multiple trophic levels. This review explores the complex networks of pathways involved in the production of protective secondary metabolites. These networks represent novel opportunities for crop improvement, particularly in breeding for drought tolerance and insect resistance. By examining key signalling networks and their interactions with abiotic and biotic stress pathways, this paper offers a resource for developing more effective strategies. Integrating metabolite profiling in breeding programs can enhance efforts to select and breed varieties that are more resilient to environmental challenges.