Impact of biotic stresses on the Brassicaceae family and opportunities for crop improvement by exploiting genotyping traits.

Utilizing RNAi, miRNA, siRNA, lncRNA and exploiting genotyping traits can help safeguard the food supply from illnesses and pest damage to Brassicas, as well as reduce yield losses caused by plant pathogens and insect pests. In the natural environment, plants face significant challenges in the form of biotic stress, due to various living organisms, leading to biological stress and a sharp decline in crop yields. To cope with these effects, plants have evolved specialized mechanisms to mitigate these challenges. Plant stress tolerance and resistance are influenced by genes associated with stress-responsive pathogens that interact with various stress-related signaling pathway components. Plants employ diverse strategies and mechanisms to combat biological stress, involving a complex network of transcription factors that interact with specific cis-elements to regulate gene expression. Understanding both plant developmental and pathogenic disease resistance mechanisms can allow us to develop stress-tolerant and -resistant crops. Brassica genus includes commercially important crops, e.g., broccoli, cabbage, cauliflower, kale, and rapeseed, cultivated worldwide, with several applications, e.g., oil production, consumption, condiments, fodder, as well as medicinal ones. Indeed, in 2020, global production of vegetable Brassica reached 96.4 million tones, a 10.6% rise from the previous decade. Taking into account their commercial importance, coupled to the impact that pathogens can have in Brassica productivity, yield losses up to 60%, this work complies the major diseases caused due to fungal, bacterial, viral, and insects in Brassica species. The review is structured into three parts. In the first part, an overview is provided of the various pathogens affecting Brassica species, including fungi, bacteria, viruses, and insects. The second part delves into the exploration of defense mechanisms that Brassica plants encounter against these pathogens including secondary metabolites, duplicated genes, RNA interference (RNAi), miRNA (micro-RNA), siRNA (small interfering RNA), and lncRNA (long non-coding RNA). The final part comprehensively outlines the current applications of CRISPR/Cas9 technology aimed at enhancing crop quality. Taken collectively, this review will contribute to our enhanced understanding of these mechanisms and their role in the development of resistance in Brassica plants, thus supporting strategies to protect this crucial crop.