Transcriptomic analysis reveals the gibberellin signaling pathway involved in the regulation of flower number in Hevea brasiliensis Muell. Arg.

The rubber tree ( Hevea brasiliensis Muell. Arg.) holds significant socio-economic value due to its contribution to the production of natural rubber (NR). However, prolonged sexual reproduction leads to nutrient depletion (N, P, K, Mg²⁺) in rubber trees, resulting in reduced latex yield and quality. Gibberellin (GA) regulates critical processes including plant growth and flowering time. To investigate the regulatory mechanism of GA on rubber tree flowering, inflorescences were sprayed with GA 3 and the GA biosynthesis inhibitor chlormequat chloride (CCC). Both treatments inhibited flowering and reduced nutrient accumulation in inflorescences and leaves. Subsequent transcriptome sequencing of inflorescences sampled at multiple time points post-treatment identified differentially expressed genes (DEGs). Analysis of these DEGs, combined with endogenous hormone detection, revealed crosstalk between plant hormone signaling pathways. Specifically, differential expression was observed in genes associated with GA signal transduction, flowering regulation, and NR biosynthesis. These findings were confirmed by real-time quantitative PCR (RT-qPCR). This study provides novel insights into the mechanisms of underlying GA signaling-mediated inhibition of flowering in rubber trees and offers potential avenues for enhancing latex production within the rubber industry. • Rubber tree flowering inhibition by gibberellin. • Reduced accumulation of nutrient content is associated with flowering inhibition. • Plant hormone signaling genes co-regulate flowering. • A theoretical model for regulating flowering in rubber trees.