Changes In Physiological Characteristics And Transcript Expression Profiles In The Latent Bud Sprouting Of Pinus Massoniana (Masson'S Pine)

The latent bud regeneration ability at the center of Pinus massoniana needle bundles is strong, and can provide a large amount of material for asexual reproduction. Topping P. massoniana can induce latent bud sprouting, but the mechanisms underlying the sprouting process are unclear. In this study, physiological indexes were examined during the sprouting of coniferous buds. Additionally, the transcript expression profile of the sprouting process was obtained by high-throughput sequencing. The results showed that increases in N and the endogenous hormone indole-3-acetic acid (IAA) could promote dormancy release and lateral branching of P. massoniana. Abscisic acid had a protective effect on the dormancy of P. massoniana buds. The expression of phenylpropanoid biosynthesis-and flavonoid biosynthesis-related genes may be induced by differences in test material synthesis and transport caused by changes in the nutrient composition of P. massoniana needles after apical topping. The observed upregulated expression of IAA transport-and response-related genes may be pertinent to the dormancy release of axillary buds. The observed activation of transcription factors within the TCP and MADS-box families may be associated with lateral meristem formation. The results of this study provide fundamental data for studying the dormancy and development of latent buds in P. massoniana.