大钟花属和黄秦艽属花部解剖

Floral Anatomy of Megacodon and Veratrilla (Gentianaceae)

对大钟花属和黄秦艽属进行了花部解剖学研究 ,并以此讨论了它们的系统演化关系。大钟花属和黄秦艽属的雌花部分花萼维管束与花冠维管束来源于同一维管束迹 ,而雄蕊维管束来源于雄蕊迹 ,每心皮具 1条背维管束 2条腹维管束 ,因此 ,花被维管束为融合型 ;黄秦艽属的雄花每个花萼、花瓣和雄蕊的维管束均来源于单个维管束迹 ,每心皮具 1条背维管束2条腹维管束 ,属于基本型。从花部解剖结构看出 ,大钟花属与假龙胆演化支关系较近 ;黄秦艽属较獐牙菜属进化。

The present paper reports the characters of floral anatomy of Megacodon (H.Smith and Veratrilla Franch.The results are used to discuss the systematic relationships of Megacodon and Veratrilla.The floral anatomy of Megacodon and female floral of Veratrilla are peculiar in the (part or all) sepal traces arising conjointly with the petal traces.In male floral of Veratrilla,the petals and sepals receive one trace each directly from the stele.These group share similar characters:the stamens receive one trace each directly from the stele and each carpel receives 1 dorsal bundle and 2 ventral bundles.According to the floral anatomical characters,it is better to treat Megacodon and Veratrilla as two distinct genera.Megacodon belongs to the 'Gentianella' evolutionary line and Veratrilla is more advanced than Swertia.