摘要: |
利用扫描电镜对14种酢浆草属植物花粉形态及表面纹饰进行观测,对其花粉形态进行聚类分析,并基于孢粉学聚类结果,探讨其种间亲缘关系。结果表明:(1)所观测14种植物花粉粒为近球形或扁球形,极面观均为三裂圆形,多数为3沟花粉粒,稀2沟(星星酢浆草)和4沟(黄花酢浆草);其中96.3%花粉粒为中等大小,3.7%为小花粉粒;不同花柱类型都表现为长雄蕊花粉比短雄蕊花粉大;外壁纹饰可分为复网状和网状两类。(2)首次发现3种存在异常花粉粒,分别为桃之辉酢浆草、一片心酢浆草及黄花酢浆草,异常花粉粒占比21.4%。(3)根据外壁纹饰可将14种划分为2大类:一类为复网状花粉,仅构巢酢浆草和果香酢浆草为该类纹饰,二者亲缘关系较近;另一类为网状花粉,对12种具网状花粉进行聚类分析可划分为4个类型,桃之辉酢浆草、双色冰淇淋酢浆草、藤双色冰淇淋酢浆草亲缘关系较近;扁平酢浆草、黄花酢浆草、纳马夸纳酢浆草及兔耳酢浆草亲缘关系较近;大花酢浆草、星星酢浆草、乳白蝴蝶叶酢浆草亲缘关心较近;吉氏酢浆草和一片心酢浆草与其它酢浆草亲缘关系较远。本研究结果表明,花粉形态相近的物种在形态上有一定的相似性,花粉形态特征可作为种间亲缘关系研究和分类划分依据,进一步为酢浆草属植物杂交育种亲本选择提供理论基础。 |
关键词: 酢浆草属 花粉形态 异型花柱 异常花粉 亲缘关系 |
DOI:10.11931/guihaia.gxzw202212056 |
分类号: |
基金项目:福建农林大学2021年度乡村振兴服务团队项目(11899170151),福建农林大学2020年度乡村振兴服务团队项目(11899170124)。 |
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Analysis of Pollen Morphology and Phylogenetic Relationship among 14 Species of Oxalis |
CHEN Shengyu, TANG Xiaoyun, XIAO Yun, HAN Ru, ZHAI Junwen, WU Shasha
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Abstract: |
Most Oxalis are highly ornamentally valuable, but their taxonomy is difficult, which greatly limits the landscape application of this genus. The pollen morphology and exine ornamentation of 14 species of the Oxalis were observed using scanning electron microscopy, and their pollen morphology was clustered and analyzed to explore their interspecific relationship based on the results of palynological clustering. The results were as follows: (1) The pollens of the 14 species observed were subspheroidal or oblatesphere, and in polar view they were all 3-colpate, of which 96.3% were medium-sized and 3.7% were small, with different style types showing the largest grains are produced in stamens with long filaments and the smallest ones in stamens with short filaments; most pollen grains were 3-colpate, sparsely 2-colpate and 4-colpate, O. stellata and O. pes-caprae, respectively; exine ornamentation can be divided into two categories: supra-areolate and reticulate. (2) For the first time, three species with aberrant pollen grains were observed, namely O. glabra, O. simplex and O. pes-caprae. The aberrant pollens exhibit as abnormal number and arrangement of the colpi, but normal exine structure. There were 2-zonocolpate grains in O. glabra, spiralaperturate grains in O. simplex, and 4-zonocolpate grains and spiralaperturate grains in O. pes-caprae. (3) The 14 species can be divided into two categories according to the exine ornamentation, one includes O. massonorum and O. nidulans with supra-areolate pollen. The other category includes 12 species with reticulate pollen. Species in the latter category can be further divided into four types: O. glabra, O. versicolor, and O. tenuifolia are more closely related; O. compressa, O. pes-caprae, O. namaquana, and O. fabaefolia are more closely related; O. bowiei, O. stellata, and O. perdicaria are more closely related; O. zeekoevleyensis and O. simplex are relatively distantly related to other Oxalis. The pollen morphology is a valuable criteria to clarify their phylogenetic relationship, and facilitate selection of parents in Oxalis cross breeding. |
Key words: Oxalis Pollen morphology Heterostyly Aberrant pollen Phylogenetic Relationship |