不同性别芦笋、天冬花发育形态解剖学比较研究

Comparative Studies on the Anatomical Morphology between Asparagus officinalis L. and A. cochinchinensis with Different Genders

【目的】解析芦笋(Asparagus officinallis L.)与天冬(A. cochinchinensis)性别分化的特征。【方法】利用石蜡切片结合镜检技术对芦笋品种紫色激情雌雄两性3种性别6个时期的花蕾;同属植物天冬雌、雄、两性株早、晚2个发育时期的花蕾以及芦笋两性花的花药进行形态发育解剖与观察。【结果】芦笋雌花在时期2 (1 mm≤长度<2 mm)雄蕊败育,雄花的时期3 (2 mm≤长度<3 mm)柱头停止发育,且两性花中成熟花粉呈育性状态;同时对天冬的解剖学结果显示:天冬雌花有明显败育雄蕊残留,雄花中有柱头退化痕迹,两性花的结构与芦笋两性花相似。【结论】从形态学上确定了芦笋性别分化的关键节点,雌花花蕾直径在1 mm之前的阶段是其性别决定关键时期,雄花花蕾直径小于2 mm的阶段为其性别决定的关键,天冬单性花形成过程与芦笋存在一致性。本研究为阐明天门冬属植物的性别决定机制奠定了基础,为芦笋与天冬全雄育种中优良材料的寻找提供了解剖证据支持。

[Purpose]In order to analyze the characteristics of sex differentiation between Asparagus officinalis L. and A. cochinchinensis.[Method]The morphology of the anatomical development of the flower buds of A. officinalis ‘purple passion’ cultivar at six different stages of three gender plants (female, male and bisexual), the flower buds of the sibling plant A. cochinchinensis at early and late stages of three gender plants (female, male and bisexual) and the anthers of bisexual flowers of A. officinalis were studied by using paraffin section and microscopic examination technology.[Result]The abortion of anther in A. officinalis female flowers occurred at stage 2 (1 mm≤length < 2 mm), the stigma stopped developing in male flowers at stage 3 (2 mm≤length < 3 mm), and the mature pollen in bisexual flowers is fertile. At the same time, the anatomical studies on A. cochinchinensis showed that the female flowers have obvious abortive stamen residues, the male flowers have degenerated stigma structure and the structure of bisexual flowers is similar as that of A. officinalis bisexual flowers.[Conclusion]The key nodes for A. officinalis sex differentiation were determined morphologically. The stage before 1mm diameter of female flower buds is the key point of female sex determination. The stage of male flower bud diameter less than 2 mm is the key point for its sex determination. The process of unisexual flower production in A. cochinchinensis was consistent with A. officinalis. This study lays a foundation for elucidating the sex determination mechanism in Asparagus spp. and provides the anatomical evidence support for searching for excellent material in all-male breeding.