Total Lignin Content in Pomegranate Seed Coat and Cloning and Expression Analysis of PgCOMT Gene

Abstract:

In order to understand the correlation between seed hardness and total lignin content in seed coat of pomegranate (Punica granatum), the seed hardness and total lignin content of six cultivars were measured by Texture Analyser and thioglycolic acid method. The results showed that the correlation coefficient was 0.9246 between seed hardness and total lignin content in seed coat. A full-length cDNA sequence of 1456 bp (GenBank accession No.: KJ713968) was cloned from pomegranate seed coat by RACE, named PgCOMT gene. Realtime quantitative PCR showed that the relative expression of PgCOMT in ‘Hongyushizi', ‘Fenpi', ‘Huiliruanzi', ‘Mengzitian' and ‘Tunisiruanzi' seed coat had a similar trend with seed hardness. The relative expression of PgCOMT declined at first, and then rose with development stage of pomegranate seed coat the last stage. These lay a foundation for further study the mechanism of soft seed traits in pomegranate.