Meta-QTL for morphological traits and pharmaceutical alkaloids in periwinkle (Catharanthus roseus (L.) 'G. Don')

Meta-analysis is a powerful method used to discern reliable genomic regions associated with quantitative traits. The objective of this study was to use a meta-QTL (MQTL) analysis method to identify the most reliable and accurate QTL controlling morphological traits and terpenoid indole alkaloids (TIAs); serpentine (S), vinblastine (VB), ajmalicine (A) and vincristine (VC) in Catharanthus roseus. A quantitative trait loci (QTL) database containing 40 QTLs retrieved from two individual mapping studies associated with 13 phytochemical and morphological traits. The results of projection of 40 putative QTLs on to the consensus genetic map showed that 18 MQTLs had a 25.88% reduction in confidence interval (CI) on C. roseus chromosomes. Co-localisation results suggested that leaves TAL and serpentine in roots (SR) with 50% and 60% frequencies were the most common QTLs associated with vindoline (V) and catharanthine (C). The MQTL.LG1.5, MQTL.LG2.2, MQTL.LG1.1, MQTL.LG1.2, MQTL.LG1.7 and MQTL.LG3.3 were the most important MQTLs and the most reliable chromosome regions for refining genetic control of the tested traits in C. roseus. The consensus map provided information for the identification of the QTL-dense genomic regions that will assist in improving the efficiency of genomic and marker-assisted selection (MAS) in pharmacological researches.