华西亚高山植物园多鳞杜鹃的开花物候与生殖特征

Flowering Phenology and Reproductive Features of Rhododendron polylepis in Huaxi Sub-alpine Botanical Garden

通过运用开花物候指标,于2014年和2015年分别对分布于华西亚高山植物园内的多鳞杜鹃进行开花物候观察、统计和分析。结果表明：多鳞杜鹃花期为4月上旬至5月初,种群、个体、花序和单花水平上花期持续时间分别为24～25、22、13～15、7～9 d。单花开花进程依其开花形态和散粉特征可分为散粉前期、散粉初期、散粉盛期和散粉末期。多鳞杜鹃具有较高的花期同步指数0.815,开花进程呈单峰曲线,表现出一种“大量、集中”的开花式样;个体相对开花强度分布频率集中在10%～50%。开花物候指数与座果数之间的相关性分析表明,始花时间与花期持续时间呈显著负相关,花期持续时间及开花数与座果数均呈显著正相关。多鳞杜鹃开花物候在种群内年度间的相似性说明,植物个体开花物候进程很大程度上是由其遗传因子决定的,而开花物候在年度间的变异,可能是由于气候环境的差异（主要是温度和降水量）引起的。“集中开花模式”、较高的同步指数和较长花期持续时间是多鳞杜鹃适应高山环境的生殖特性。

By applying flowering phenology indicators, observation, statistics and analysis of flowering phenology of Rhododen- dron polylepis distributed in West China Subalpine Botanical Garden were conducted in 2014 and 2015, respectively. The flowering period of R. polylepis is in the first ten days in April to early May, and flowering duration period of species, indi- vidual, single flower level is 24-25 d, 22 d, 13-15 d and 7-9 d, respectively. Single flowering processes, according to their flowering shape and pollinating characteristics, can be divided into pre-pollinating, initial pollinating, peak pollina- ting and [ate pollinating phases. R. polylepis has a relatively high index of synchronous flowering of 0.815, and blooming process is with a single peak curve, showing a ＂substantial, concentrated＂ flowering pattern, and individual relative flow- ering intensity frequency distribution is concentrated in 10%-50%. By the correlation analysis between flowering phenology indicators and fruiting number, initial flowering time has significant negative correlation with flowering duration time, and flowering duration time is significantly positively correlated with fruiting number. By comparing R. polylepis flowering phe- nology among populations in different years, plant individual flowering phenology process is largely determined by genetic factors, and the inter-annual variation of flowering phenology may be caused by differences in climate and environment （mainly temperature and rainfall）. ＂Centralized flowering mode＂, higher synchrony index and longer flowering duration are reproductive characteristics of R. polylepis to adapt to high mountain environment.