摘要 | 为了更好地比较十字花科(Brassicaceae)植物花粉的形态特征,使用光学显微镜和扫描电镜观察诸葛菜〔Orychophragmus violaceus (Linn.) O. E. Schulz〕、芸薹(Brassica campestris Linn.)、欧洲油菜(B. napus Linn.)2个品种(叶缘具锯齿和叶缘无锯齿)、芥菜〔B. juncea (Linn.) Czern.〕和萝卜(Raphanus sativus Linn.)的花粉形态,并比较6个材料花粉的几何形态参数差异。结果表明:6个材料花粉的极面观为三裂圆形,欧洲油菜(叶缘具锯齿)和芥菜花粉的赤道面观为椭球形,其余4个材料花粉的赤道面观为长椭球形,并且6个材料花粉均具三沟;极轴长和赤道轴长分别为22.44~28.19和19.09~24.25 μm,极轴长与赤道轴长的比值为1.07~1.18;赤道面直径和极面直径分别为20.78~26.15和18.93~25.21 μm;除诸葛菜花粉外壁具2层结构(即外壁外层和基层)外,其余材料花粉外壁均具3层结构(即外壁外层、基层和外壁内层),厚度1.84~2.46 μm;极面弧形弯曲率为0.34~0.39。诸葛菜花粉网眼内无疣状结构,其余材料花粉网眼内均有疣状结构,其中,芸薹花粉网眼内的疣状结构最明显,芥菜花粉网眼内的疣状结构最不明显;6个材料花粉的网眼密度为0.3~0.9 μm-2,网眼直径为0.86~1.44 μm。根据上述花粉形态特征,6个材料可分成2个大类,其中,诸葛菜单独为一类,其花粉赤道面观为长椭球形,外壁较薄,网眼内无疣状结构,且网眼直径小、密度大;其余材料为另一类,其花粉赤道面观为椭球形或长椭球形,外壁较厚,网眼内有疣状结构,且网眼直径大、密度小。研究结果显示:6个材料花粉的形状和大小、外壁层次结构和厚度、极面弧形弯曲率、网眼内的疣状结构及网眼密度和大小存在一定差异。花粉网眼内的疣状结构及部分花粉几何形态参数差异可用于区分诸葛菜与其他5个材料,但光学显微镜下的花粉外壁层次结构不宜作为十字花科植物花粉鉴别的依据。 |
Abstract | To better compare the pollen morphological characteristics of Brassicaceae species, pollen morphology of Orychophragmus violaceus (Linn.) O. E. Schulz, Brassica campestris Linn., two cultivars of B. napus Linn. (leaf margin with serration and leaf margin without serration), B. juncea (Linn.) Czern., and Raphanus sativus Linn. were observed by using light microscope and scanning electron microscope, and the differences in pollen geometrical parameters among six species/cultivars were compared. The results show that the pollen polar views of six species/cultivars are trilobed round, and the pollen equatorial views of B. napus (leaf margin with serration) and B. juncea are oblate, while those of other four species/cultivars are prolate, and the six species/cultivars all have three colpi; the length of polar axis and equatorial axis are 22.44-28.19 and 19.09-24.25 μm, respectively, and the ratio of length of polar axis to length of equatorial axis is 1.07-1.18; the diameter of equatorial plane and polar plane are 20.78-26.15 and 18.93-25.21 μm, respectively; except that the pollen exine of O. violaceus is two-layer structure (which are sexine and foot layer), that of other species/cultivars are all three-layer structure (which are sexine, foot layer, and endexine) with the thickness of 1.84-2.46 μm; the arc curvature of polar view is 0.34-0.39. There is no verrucous structure in pollen lumina of O. violaceus, while there are verrucous structures in pollen lumina of other species/cultivars, in which, the verrucous structure in pollen lumina of B. campestris is the most evident, while that of B. juncea is the least evident; the pollen lumen densities of six species/cultivars are 0.3-0.9 μm-2, and the lumen diameter is 0.86-1.44 μm. Based on above pollen morphological characteristics, the six species/cultivars can be divided into two categories, in which, O. violaceus belongs to one category individually, its equatorial view is prolate, the exine is relatively thin without verrucous structure in lumina, and the lumen diameter and density are small and large, respectively; other species/cultivars belong to the other category, their equatorial views are oblate or prolate, the exine is relatively thick with verrucous structures in lumina, and the lumen diameter and density are large and small, respectively. It is suggested that there are a certain differences in pollen shape and size, exine hierarchical structure and thickness, arc curvature of polar view, verrucous structure in lumina, and lumen density and size of six species/cultivars. Differences in verrucous structure in the pollen lumina and some pollen geometrical parameters can be used to distinguish O. violaceus from other five species/cultivars, but the hierarchical structure of pollen exine under light microscope is not appropriate to be used as reference for pollen classification of Brassicaceae species. |
关键词 | 十字花科; 花粉形态; 几何形态参数; 疣状结构 |
Key words | Brassicaceae; pollen morphology; geometrical parameter; verrucous structure |
作者 | 陈相洁1,2, 毛礼米1,3, 潘昱安4,5, 王英浩1,2 |
所在单位 | 1. 中国科学院南京地质古生物研究所 现代古生物学和地层学国家重点实验室, 江苏 南京 210008; 2. 中国科学院大学, 北京 100049;3. 中国科学院大学南京学院, 江苏 南京 211100; 4. 英国自然历史博物馆, 伦敦 SW7 5BD; 5. 帝国理工学院, 伦敦 SW7 2AZ |
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基金项目 | 国家自然科学基金面上项目(41877437); 中国科学院战略性先导专项B类子课题(XDB26030402) |