Morphological and anatomical comparison of mericarps from different types of umbels of Heracleum sosnowskyi / Sosnovskio barščio skirtingų tipų žiedynų merikarpių morfologinės ir anatominės sandaros palyginamoji analizė

Abstract

Sosnowsky’s hogweed (Heracleum sosnowskyi Manden.) mericarps were collected from satellite and stem branch umbels for comparative anatomical investigation. Located near Vilnius city, the habitat of Heracleum sosnowskyi, formerly a natural forest edge has recently been densely occupied by plants of this species. SEM micrographs of abaxial and adaxial surfaces of mericarps obtained from satellite and stem branch umbels of H. sosnowskyi were similar, but morphometrical analysis revealed statistically significant differences in mericarps collected from satellite umbels, which were longer and wider than mericarps from stem branch umbels. The data on longitudinal sections of H. sosnowskyi mericarps clearly showed that embryos of satellite umbels were at later torpedo stage compared to embryos of stem branch umbels, which were at earlier heart stage. These data represent unequal development of the embryos in mericarps from different types of umbels. Such different development can be treated as an adaptation of the invasive plant to occupy the current habitat and survive in the seed bank by allowing the embryo to complete development within a seed and germinate when new conditions permit.

Heracleum sosnowskyi seed development under the effect of exogenous application of GA3

“…The studied area occupied 0.415 ha and was located between 54°758587′N and 25°260138′E. Detailed description of the location is in Jurkonienė et al (2016). For our research, satellite umbels were treated and mericarps were collected from randomly selected plants.…”

Identification of Heracleum sosnowskyi-Invaded Land Using Earth Remote Sensing Data

“…These results are important from a theoretical point of view and can also be helpful in selection of effective measures for management and eradication of H. sosnowskyi [5]. In Lithuania, H. sosnowskyi was included in the list of plants harmful for human health that should be eradicated [6,7]. Three meters high H. sosnowskyi (and even higher) choke growing of a majority of local plants.…”

Heteromericarpy of Heracleum sosnowskyi Manden. (Umbelliferae = Apiaceae)

“…Это свидетельствует о том, что у части образовавшихся мерикарпиев зародыш полностью развит и отсутствуют механизмы морфофизиологического торможения. Схожие данные были получены S. Jurkonienė et al (2016). Прорастание семян H. sosnowskyi, собранных в конце лета -начале осени, растянуто: так, в лабораторных условиях появление первых 3-5 всходов отмечали за 5-7 дней.…”

“…Показано, что местоположение семени в соцветии определяет степень его развития. Эмбрионы мерикарпиев, сформированные в центральном зонтике, к моменту созревания достигают фазы «торпеды», в то время как эмбрионы мерикарпиев в зонтиках первого порядка достигают фазы «сердца», что рассматривается как адаптация растений для занятия среды обитания и способствует формированию банка семян в почве (Krinke et al, 2005, Jurkonienė et al, 2016.…”