Integration analysis of transcriptome and metabolome reveals role of piceatannol in regulation of fruit drop in Chinese bayberry (Morella rubra Sieb. et Zucc.)

• Preventation of fruit drop is not only essential for increasing production in horticultural crop but also directly determines fruit quality. Although the hormones and other plant growth regulators have been investigated and applied in production, there is still lack of a natural, effective and available option to reduce fruit drop.• Piceatannol, as a natural phenolic compound, has been reported for positive medical treatment in human. In this study, we unveiled the regulatory role of piceatannol in Morella rubra ( M. rubra ), that sufficiently inhibit fruit drop before harvesting and better than the application of 4-chlorophenoxyacetic acid (4-CPA).• Our data suggested that piceatannol was implicated in fruit drop via increasing auxin and zeatin levels in M. rubra during fruit development. The integrative analysis of transcriptome and metabolome further revealed that piceatannol-regulated pathway in decrease of fruit drop is related with programmed cell death and plant hormone signal transduction in M. rubra .• This work provides a theoretic basis for the inhibitory role of piceatannol against fruit drop, aiming to offer a potential and sufficient mean for improving horticultural crop yields.