MiRNA precursor‐derived SSR marker‐mediated genotyping of tea (Camellia sinensis) cultivars with varying health benefit traits

Abstract

AbstractBesides its popular refreshing value, tea is globally consumed as a potential health beverage. Health benefit traits primarily rely on some regulatory networks of different metabolic pathways. In tea, the trait‐specific simple sequence repeat (SSR) markers are still insufficient, which could be used for marker‐assisted breeding technique. MicroRNAs are endogenous, non‐coding, short RNAs directly involved in regulating gene expressions at the post‐transcriptional level. It has been found that differences in miRNA precursor gene sequences interfere their structure formation and obstruct subsequent function. SSR motifs within the putative miRNA precursor genes have been identified followed by experimental validation of their existence and variation exclusively in tea. Simultaneously, diverse commercial accessions of Indian tea were undergone rigorous phenotyping during three plucking seasons to assess 20 chemotypic traits by high‐throughput techniques. Six miRNA‐SSR marker‐generated bands consisted the putative trait‐associated loci. Newly developed microRNAs (mi408, miR5021a and miR2863) precursor‐derived SSR markers, miSSR‐03, miSSR‐11 and miSSR‐14, executed convincing results in distinguishing tea cultivars with contrasting health benefit traits. This is in accordance with the earlier reports where mi408, miR5021a and miR2863 have been found to be involved in cellular pathways conferring tolerance to oxidative stress. Consequently, these markers can be used further as suitable choice to select promising tea genotypes with sound antioxidant quality.