当前位置: X-MOL 学术Aerobiologia › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Morphophysiological characteristics of pollen grains produced by bisexual inflorescences of silver birch (Betula pendula Roth.)
Aerobiologia ( IF 2 ) Pub Date : 2020-11-21 , DOI: 10.1007/s10453-020-09678-0
Łukasz Grewling , Łukasz Piosik , Piotr Szkudlarz

Silver birch (Betula pendula Roth., family Betulaceae, order Fagales) produces pollen grains in pendulous male (staminate) inflorescences (catkins), that are formed 1 year before flowering. Birch catkins elongate during summer months until they reach the dormancy phase (winter rest). At this stage catkins are short, dense and contain microspores. In the next season, after breaking the dormancy, the development of pollen grains is renewed (Dahl and Strandhede 1996; Holm 1994). A few weeks later, in Poland, usually in April and May, mature pollen grains are released from long fully developed catkins (Grewling et al. 2012). In contrast, female (pistillate) inflorescences overwinter as primordia and emerge just before pollination after breaking off the short shoot buds in which they developed (Holm 1994). Female flowers are greenish, erect and much thinner and shorter than the male catkins. As a rule, the inflorescences of silver birch (both male and female) are therefore unisexual, located separately on the tree (Hynynen et al. 2010). During the field surveys in 2019 and 2020, we observed bisexual catkins with female flowers in its basal part and male flowers in the distal region in two individuals of Betula pendula growing in Poznań (Western Poland). Bisexual catkins have been previously reported in B. pendula (Kosmin 1982) and the morphological structure of bisexual catkins of B. pubescens has been thoroughly described by Tolstopyatenko (1974). The information about pollen grains produced by these catkins are however very scarce and limited only to pollen grain diameter and germination data (Tolstopyatenko 1974, Makhnev and Korobchenko 1976). In this short communication, we present the morphophysiological characteristics of pollen grains produced by bisexual catkins of B. pendula with particular emphasis on such features as: vitality, germinability and allergenicity. The possible evolutionary significance of this phenomenon, with respect to projected shifts in silver birch distribution Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10453-020-09678-0) contains supplementary material, which is available to authorized users.

中文翻译:

白桦双性花序产生的花粉粒的形态生理特征(Betula pendula Roth.)

银桦 (Betula pendula Roth., Betulaceae, order Fagales) 在开花前 1 年形成的下垂雄性(雄蕊)花序(柳絮)中产生花粉粒。桦木柳絮在夏季延长,直至进入休眠期(冬季休息)。在这个阶段,柳絮短而密,含有小孢子。在下一个季节,打破休眠后,花粉粒重新发育(Dahl and Strandhede 1996; Holm 1994)。几周后,在波兰,通常在 4 月和 5 月,成熟的花粉粒从长期完全发育的柳絮中释放出来(Grewling 等人,2012 年)。相比之下,雌性(雌蕊)花序作为原基越冬,并在它们发育的短芽脱落后在授粉前出现(Holm 1994)。雌花是绿色的,直立,比雄性柳絮更薄更短。通常,银桦的花序(雄性和雌性)因此是单性的,分别位于树上(Hynynen 等人,2010 年)。在 2019 年和 2020 年的实地调查中,我们观察到生长在波兹南(波兰西部)的两个 Betula pendula 个体的基部有雌花,远端有雄花的双性柳絮。早先在 B. pendula (Kosmin 1982) 中报道了双性柳絮,Tolstopyatenko (1974) 已经彻底描述了 B. pubescens 的双性柳絮的形态结构。然而,关于这些柳絮产生的花粉粒的信息非常稀少,并且仅限于花粉粒直径和发芽数据(Tolstopyatenko 1974,Makhnev 和 Korobchenko 1976)。在这个简短的交流中,我们展示了由 B. pendula 的双性柳絮产生的花粉粒的形态生理特征,特别强调了以下特征:活力、发芽性和过敏性。这种现象的可能进化意义,关于白桦树分布的预计变化 电子补充材料 本文的在线版本 (https://doi.org/10.1007/s10453-020-09678-0) 包含补充材料,其中可供授权用户使用。
更新日期:2020-11-21
down
wechat
bug