桔梗开花物候与生殖特征

Flowering Phenology and Reproductive Characteristics of Platycodon grandiflorum

研究了白花桔梗和紫花桔梗的开花物候和生殖特征,分析了2个群体的单花开花动态、开花物候指数和结实率,以及开花物候指数对桔梗生殖成功的影响。结果表明：桔梗花期为7月初至9月中下旬,桔梗开花一般历时35～47 d,单株花期一般为26～31 d,单花花期一般为5～7 d。2个群体个体水平的开花振幅曲线呈单峰型曲线,并且开花同步指数较高,表现出一种集中开花式样。相关分析表明：白花桔梗中,坐果数与开花高峰期和花蕾数呈极显著正相关,紫花桔梗中坐果数与花蕾数呈极显著正相关。开花物候变异系数分析表明：2个群体在总花数、开花振幅、开花高峰期、终花期和结实率差异极显著,白花桔梗与紫花桔梗在同步性指数、花期持续时间、始花期和坐果数无显著性差异。

White and purple Platycodon grandiflorum populations were taken as test objects to study their phenology and reproductive characteristics.Single flowers＇ floral dynamics,flowering phenology indexes and fruit setting rate of the two populations were analyzed,and the effects of flowering phenology indexes on the reproductive success of P.grandiflorum were studied.The flowering span of P.grandiflorum was from early July to mid and late September,and the flowering phase of the population,individual,and single flower lasted approximately 35 ～ 47,26 ～ 31,and 5 ～ 7 days,respectively.The flowering amplitude curves of the populations at individual level were of single peak and higher synchrony,taking on a＂mass-flowering＂pattern.Correlation analysis showed that white flower P.grandiflorum fruit setting number had significantly positive correlation with flourishing flowering date and bud number and purple flower P.grandiflorum fruit setting number had significantly positive correlation with bud number.Variation coefficient analysis of flowering phenology indicated that there existed significant differences in the total flower number,flowering amplitude,peak flowering date,last flowering date and fruit setting,but less difference in synchrony index,first flowering date,flowering duration and fruit setting number among the two populations.