Comparative Transcriptomics of Mango (Mangifera indica L.) Cultivars Provide Insights of Biochemical Pathways Involved in Flavor and Color

Mango is an economically important fruit crop of many tropical and subtropical countries. Recently, leaf and fruit transcriptomes of mango cultivars grown in different geographical regions have characterized. Here, we presented comparative transcriptome analysis of four mango cultivars i.e. cv. Langra, cv. Zill, cv. Shelly and cv. Kent from Pakistan, China, Israel and Mexico respectively. De-novo sequence assembly generated 30,953-85,036 unigenes from RNASeq datasets of mango cultivars. KEGG pathway mapping of mango unigenes identified terpenoids, flavonoids and carotenoids biosynthetic pathways involved in flavor and color. The analysis revealed linalool as major monoterpenoid found in all cultivars studied whereas, monoterpene -terpineol was specifically found in cv. Shelly. Ditepene gibberellin biosynthesis pathway was found in all cultivars whereas, homoterpene synthase involved in biosynthesis of 4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT; an insect induced diterpene) was found in cv. Kent. Among sesquiterpenes and triterpenes, biosynthetic pathway of Germacrene-D, an antibacterial and anti-insecticidal metabolite was found in cv. Zill and cv. Shelly. Two bioactive triterpenes, lupeol and {beta}-amyrin were found in cv. Langra and cv. Zill. Unigenes involved in biosynthesis of carotenoids, {beta}-carotene and lycopene, were found in cultivars studied. Many unigenes involved in flavonoid biosynthesis were also found. Comparative transcriptomics revealed naringenin (an anti-inflammatory and antioxidant metabolite) as central flavanone responsible for biosynthesis of an array of flavonoids. The present study provided insights on genetic resources responsible for flavor and color of mango fruit.