Home – Home – Jornals – Flora and Vegetation of Asian Russia 2021 number 2

We studied the flowering biology of perfect and staminate flowers, the sequence of flowers blooming in umbellets and umbels in Chaerophyllum aromaticum L., a biennial or perennial taproot polycarpous herb. Our observations used generally accepted methods for studying flowering biology in the Moscow region in 2017-2019. The flowering sequence of umbels in C. aromaticum synflorescence corresponds to the “Chaerophyllum prescottii” blooming model described in the literature. According to this model, the stigma phase of flowers on shoots of the same order coincides with the staminate phase of flowers on shoots of the next order. So, the geitonogamy does not exclude between flowers of umbels on shoots of different orders. The perfect flowers are strongly protandrous, their anthers mature and are exposed much earlier than their stigmas. So, in perfect flowers, the possibility of transferring their own pollen to the stigmas (and therefore also autogamy) is completely excluded. In perfect flowers, the stigma phase is longer than the staminate one: the first lasts 2-3 days, while the second lasts only 1 day. The lifespan of perfect flowers - from opening the anthers of the stamens to the end of the stigma phase - is 5-7 days, and 1 day for staminate flowers. The lifespan of C. aromaticum flowers directly depends on their sexual form and location in synflorescence. The lifespan of perfect flowers decreases in the direction from the peripheral umbellets to the inner ones within the umbels, with an increase in the branching order of the shoot. Each umbellet and umbel goes through three phases consecutively: staminate, simultaneous functioning of male and female generative structures, and stigma. Thus, these phases are not clearly demarcated in time, and it does not completely exclude geitonogamous pollination within umbellets and umbels on shoots of the same order. The perfect and staminate flowers of C. aromaticum are characterized by a morning opening rhythm with a maximum at 9 am.