Molecular Pathogens 2024, Vol.15, No.1, 30-39 http://microbescipublisher.com/index.php/mp 36 co-evolutionary process is evident in the study by Cui et al. (2015), which describes how plants and pathogens are engaged in a dynamic battle, with each side constantly adapting to the other's strategies. Additionally, the rapid evolutionary rates of defense genes and their regulators in plants, driven by the need to keep pace with evolving pathogen threats. 7 Advances in Genomic and Biotechnological Approaches 7.1 Genomic sequencing and functional genomics Genomic sequencing and functional genomics have significantly advanced our understanding of the molecular mechanisms underlying tea plant resistance to major pathogens. The advent of high-throughput sequencing technologies has enabled the identification of numerous resistance (R) genes and susceptibility (S) genes, which play crucial roles in plant-pathogen interactions. These technologies have facilitated the discovery of quantitative trait loci (QTLs) associated with disease resistance, providing valuable insights into the genetic basis of resistance (Kushalappa et al., 2016). Additionally, metabolomics and other OMICs tools have elucidated the complex biochemical pathways involved in the plant's defense mechanisms, highlighting the importance of resistance-related (RR) proteins and metabolites in reinforcing cell walls and inhibiting pathogen spread. 7.2 CRISPR and gene editing techniques CRISPR/Cas9 and other genome editing techniques have revolutionized the field of plant disease resistance by enabling precise and targeted modifications of plant genomes. CRISPR/Cas9, in particular, has become the preferred tool due to its efficiency, simplicity, and low risk of off-target effects (Borrelli et al., 2018; Mushtaq et al., 2019). This technology has been successfully used to knock out or modify S genes, thereby enhancing resistance to a wide range of pathogens, including viruses, bacteria, and fungi (Langner et al., 2018; Zaynab et al., 2020). The ability to create transgene-free, disease-resistant crop varieties using CRISPR/Cas9 has significant implications for sustainable agriculture and food security (Zaidi et al., 2018; Ahmad et al., 2020). Moreover, the continuous evolution of CRISPR/Cas9 variants aims to address challenges such as off-target effects, further improving the precision and effectiveness of this technology (Das et al., 2019). 7.3 Transgenic approaches for disease resistance Transgenic approaches have also been employed to enhance disease resistance in tea plants. By introducing specific R genes or antimicrobial peptides into the plant genome, researchers have developed transgenic plants with improved resistance to various pathogens. These transgenic plants often exhibit broad-spectrum resistance, making them valuable assets in the fight against plant diseases. Additionally, the integration of CRISPR/Cas9 technology with transgenic approaches has opened new avenues for developing crops with enhanced resistance. For instance, CRISPR/Cas9 can be used to precisely insert or replace genes in the plant genome, thereby creating cisgenic plants that retain the benefits of traditional breeding while incorporating advanced genetic modifications (Kushalappa et al., 2016; Borrelli et al., 2018; Zaynab et al., 2020). 8 Concluding Remarks The molecular mechanisms of tea plant resistance to major pathogens have been extensively studied, revealing a complex interplay of genetic, biochemical, and microbial factors. Transcriptome analyses have identified numerous defense-related genes and pathways involved in resistance to blister blight, anthracnose, and tea gray blight diseases. For instance, key defense-related transcripts such as RPM1, RPS2, and RPP13 have been implicated in the salicylic acid and jasmonic acid pathways, which are crucial for overcoming the virulence of Exobasidium vexans. Similarly, the resistance mechanisms against Colletotrichum spp. involve the activation of defense signaling pathways and the development of resistant cultivars. Metabolomic and microbiome studies have highlighted the role of phenolic acids, flavonoids, and specific microbial genera in enhancing resistance to Pestalotiopsis theae 3. Additionally, strategic transcriptomic comparisons have provided insights into the molecular responses to Ectropis oblique, identifying key genes and pathways involved in jasmonate/ethylene signaling and terpenoid synthesis.
RkJQdWJsaXNoZXIy MjQ4ODYzNA==