Page 155 - 《广西植物》2025年第12期
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12 期                  胡梦等: 中国荞麦属 11 种植物的花粉形态及其分类学意义                                       2 2 9 7

                 Abstract: Fagopyrum plants serve as a gene pool for the genetic improvement of cultivated buckwheatꎬ but the
                 phylogenetic status and species identification within this genus remain controversial. To explore the morphological
                 characteristics of Fagopyrum and its taxonomic significanceꎬ the pollen morphology of 11 species and 2 subspecies of
                 Fagopyrum was observed using scanning electron microscope. The results were as follows: (1) The pollen shape of the
                 Fagopyrum species varied from subspheroidal to prolateꎬ and the pollen sizes varied significantly among speciesꎬ of
                 whichꎬ the pollen of F. tataricum ssp. potanini and F. gracilipes were bigꎬ that of F. callianthum was smallꎬ that of the
                 rest were medium ̄sized. (2) The pollen exine sculpture was finely reticulate in all species. Howeverꎬ there were obvious
                 differences in the size and density of pollen surface perforation among different species. (3) Cluster analysis showed the
                 pollen morphology of F. tataricum ssp. potaniniꎬ F. lineareꎬ F. tataricumꎬ F. urophyllumꎬ and F. callianthum had
                 similar characteristicsꎬ such as the germination furrow was small in length and widthꎬ the pollen shape was subglobose or
                 oblongꎬ and the pollen size was medium or small. F. densovillosumꎬ F.caudatumꎬ F. staticeꎬ F. rubifoliumꎬ F. dibotrysꎬ
                 and F. macrocarpum were similarꎬ with some characteristicsꎬ such as germination furrow of medium length and widthꎬ
                 pollen shape subglobose or oblongꎬ and all having medium ̄sized pollenꎬ while the pollen morphology of F. esculentum
                 ssp. ancestralis and F. gracilipes were similar and distinct from other congenersꎬ characterized by the widest luminaꎬ the
                 broadest murusꎬ the largest lumina sizeꎬ and the longest and the widest germinal apture. The grains were prolate and
                 ranked as the largest in size among all species examined. In conclusionꎬ the pollen of Fagopyrum has the common
                 characteristics of subglobose or oblong shapeꎬ exine sculpture is finely reticulateꎬ tricolporate aperatureꎬ which are
                 clearly different from other genera of Polygonumꎬ which means that it can be used as a reference to determine the
                 phylogenetic status of this genus. Although there are differences in pollen morphology between taxaꎬ the low resolution is
                 not enough to distinguish the species of Fagopyrum.
                 Key words: Fagopyrumꎬ pollen morphologyꎬ exine sculptureꎬ cluster analysisꎬ taxonomy



                荞麦属( Fagopyrum Miller) 植物对逆境( 如干               关系也一直未确定ꎮ 例如ꎬChen(1999) 根据金荞
            旱、低温、酸性等)具有极高的耐性ꎬ是栽培荞麦遗                            麦 [F. dibotrys ( Trev.) Meisn.] 的形态及核型差

            传改良的理想基因资源( 王安虎等ꎬ2006ꎻ杨玉霞ꎬ                         异ꎬ应 将 其 进 一 步 划 分 为 3 个 种ꎬ 即 大 野 荞 麦
            2008)ꎮ 该属植物广布于亚洲和欧洲ꎬ其中中国西                          (F. megaspartanum)、毛野荞麦(F. pilus)和金荞麦
            南(四川、云南、贵州、西藏) 是荞麦属植物的起源                           (F. dibotrys)ꎮ 然而ꎬ周美亮等(2021) 则认为ꎬ基

            中心、分布区和多样化中心( Chenꎬ 1999ꎻ唐宇等ꎬ                      于对花、瘦果的解剖观察结果ꎬ三者应为同一物
            2019ꎻ文雯ꎬ2019ꎻFan et al.ꎬ 2021)ꎮ 据«中国植物             种ꎮ Wang 等(2017) 基于瘦果棱角有翅的形态特
            志»记载ꎬ该属约有 15 种ꎬ我国有 10 种 1 个变种                      征ꎬ发表了新种 F. longzhoushanenseꎻ而其他学者则

            (李安仁ꎬ1998)ꎬ其中苦荞麦和甜荞麦为栽培种ꎮ                          认为瘦果棱具翅不足以作为荞麦属物种的分类依
            但是ꎬ 近 年 来 荞 麦 属 不 断 有 新 种 被 报 道ꎬ 如 F.              据ꎬ除在果实的棱上具翅以外ꎬF. longzhoushanense
            tibeticum、 F. longzhoushanense、 F. longistylum、 F.  的形态特征、染色体数与 F. pugense 一致ꎬ所以将
            snowdenii 等ꎬ目前该属约 20 种( Tian et al.ꎬ 2011ꎻ         F. longzhoushanense 作 为 F. pugense 的 异 名 处 理
            Wang et al.ꎬ 2017ꎻOhsako & Liꎬ 2020ꎻZhang et al.ꎬ  (唐宇等ꎬ2019)ꎮ 这些争议的存在表明ꎬ仅仅基于
            2021ꎻ周美亮等ꎬ2021ꎻMin et al.ꎬ 2023)ꎮ 荞麦属              植物形态特征和染色体特征ꎬ无法明确荞麦属的
            是否 该 独 立 成 属 一 直 是 分 类 学 者 争 议 的 焦 点               系统地位及物种的种间关系ꎬ需要更多的证据予
            (Chenꎬ 1999ꎻ 唐宇等ꎬ2019)ꎬ主要有两个观点ꎮ                    以支撑ꎮ
            一种观点认为荞麦属应归入蓼属( Polygonum L.)                          一些研究表明ꎬ花粉形态特征能反映出种属
            中( Stewardꎬ 1930ꎻGraham & Woodꎬ 1965)ꎬ而 另          特征ꎬ因 此 可 以 用 来 探 讨 荞 麦 属 种 间 系 统 关 系
            一种 观 点 认 为 应 该 将 其 作 为 独 立 的 属 处 理                 (Hedbergꎬ1946)ꎮ 与植物的茎、叶等器官的表型
            ( Graham & Woodꎬ 1965ꎻ Ohnishi & Matsuokaꎬ         特征相比ꎬ花粉形态具有较强的遗传保守性( 袁涛
            1996ꎻ李安仁ꎬ1998)ꎮ 此外ꎬ该属部分物种的种间                       和王莲英ꎬ1999ꎻ薛美玲等ꎬ2024)ꎬ不易受外界因
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