Growth rhythm of Zenia insignis seedlings from four provenances.

【Objective】The purpose of this study was to understand the seedling growth rhythm of Zenia insignis from four different provenances. 【Method】The container seedling growth rhythm of Z. insignis was observed periodically. The growth curves of seedling height and ground diameter were built using the Logistic equation,and growth parameters were estimated.【Result and conclusion】The result showed that the growth rhythm showed a "S"type curve. The determination coefficient varied from 0. 954 to 0. 983,and the fitting degree reached an extremely significant level. Therefore,seedling growth dynamics could be fitted by the Logistic equation. Different provenances showed different growth rhythms,but seedling growth of Z. insignis could be divided into 4 stages in general. The seedling germination stage was before March 1st; the early growth stage was from March 1st to April 30 th in height,and from March 1st to April 9th in diameter; the fast-growing stage was from April 30 th to September 20 th in height,and from April 9th to October 12 th in diameter; late growth stage was after September 20 th in height and after October 12 th in diameter. However,different provenances of Z. insignis showed differences in the starting and ending time and the duration of the 4 growth stages.