| 摘要: |
| 芭蕉属（Musa L.）是芭蕉科模式属，种质资源丰富，是香蕉遗传育种的重要基因库。然而，该属种间界定模糊，分类系统存在争议且雌雄蕊的微形态研究匮乏。为明晰芭蕉属野生种雌雄蕊的微形态特征，并评估其在分类学中的价值，该研究以分属真蕉组（sect. Musa，n=x=11）和美蕉组（sect. Callimusa，n=x=10/9/7）的10个野生种为材料，利用体视显微镜、石蜡切片及扫描电镜技术，系统观察了其雌雄蕊的宏观形态、解剖结构及超微结构。结果表明：（1）雄蕊特征：真蕉组物种花药长度大于或近等于花丝长度，美蕉组的河口指天蕉（M. splendida）花药长度则远小于花丝。花粉均为近球形，外壁纹饰可分为“脑纹瘤状”和“细颗粒/磨砂状”两种主要类型，组间差异显著。花粉直径最大的为美蕉组的河口指天蕉[(133.13±8.05) μm]，最小的为真蕉组的朝天蕉（M. velutina）[(73.04±6.19) μm]。(2) 雌蕊特征：真蕉组物种柱头多为匙状，美蕉组（M. splendida）为头状。所有物种柱头均为湿柱头，花柱多为实心型，仅真蕉组的野蕉（M. balbisiana）具开放型花柱道。柱头乳突细胞的形态、排列方式及分泌物状态可稳定区分物种及不同发育时期（可授期、伸长期、衰老期）。该研究认为，芭蕉属雌雄蕊的微形态特征（花药/花丝长度比、花粉外壁纹饰、花柱道类型、柱头乳突细胞形态等）遗传保守性强、性状稳定，可作为属下分组（真蕉组、美蕉组）及种间鉴定的重要形态学依据。该研究为芭蕉属种质资源评价、系统分类学的进一步完善以及香蕉遗传育种中的亲本选择提供了关键的基础数据。 |
| 关键词: 芭蕉属，雌蕊，雄蕊，微形态学，分类学，形态解剖 |
| DOI：10.11931/guihaia.gxzw202604030 |
| 分类号: |
| 基金项目:云南省基础研究计划项目（202501AT070030）；云南省重点研发计划项目（202503AK140037）；云南省技术创新人才培养计划项目（202205AD160038）。 |
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| Morpho-anatomy and ultrastructure of pistil and stamen in ten wild species of Musa (Musaceae) |
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YANG Tianyan, TIAN Qin, ZHAO Ziai, MENG Zhencheng, ZHANG Jianchun, ZHI Jiazeng*
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Honghe Tropical Agriculture Institute of Yunnan, Hekou 661300, Yunnan, China
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| Abstract: |
| The genus Musa L., the type genus of Musaceae, possesses abundant wild germplasm resources and serves as a crucial gene bank for banana genetic breeding. However, species delimitation within this genus remains ambiguous, leading to taxonomic controversies, and micromorphological studies on its stamens and pistils are scarce. This study aims to clarify the micromorphological characteristics of stamens and pistils in wild Musa species and evaluate their taxonomic significance. Using ten wild species representing sect. Musa (n=x=11) and sect. Callimusa (n=x=10/9/7), we systematically observed the phenotypic, cellular, and ultrastructural features of stamens and pistils using stereomicroscopy, paraffin sectioning, and scanning electron microscopy (SEM). The results were as follows: (1) Stamen characteristics: In sect. Musa, anther length was greater than or nearly equal to filament length, whereas in M. splendida (sect. Callimusa), anther length was much shorter than the filament. Pollen grains were subspheroidal in all species. The exine ornamentation was classified into two main types: “cerebroid-tuberculate” and “fine-grained/frosted”, with significant differences between the two sections. The largest pollen diameter was observed in M. splendida [(133.13 ± 8.05) μm], and the smallest in M. velutina [(73.04 ± 6.19) μm]. (2) Pistil characteristics: Most species in sect. Musa possessed a spatulate stigma, while M. splendida had a capitate stigma. All stigmas were of the “wet” type. The styles were predominantly solid, except for M. balbisiana (sect. Musa), which had an open stylar canal. The morphology, arrangement, and secretory state of stigma papillary cells could reliably distinguish species and different developmental stages (receptive, elongation, senescence). The study concludes that the micromorphological characteristics of stamens and pistils in Musa (anther/filament length ratio, pollen exine ornamentation, stylar canal type, stigma papillae morphology) are highly conservative and stable. These traits serve as valuable morphological evidence for infrageneric classification (sect. Musa vs. sect. Callimusa) and species identification. This research provides fundamental data for germplasm evaluation, taxonomic refinement, and parental selection in banana genetic breeding programs. |
| Key words: Musa, pistil, stamen, micromorphology, taxonomy, morpho-anatomy |
