THE FEATURES OF GYNODIOECIOUS FLOWERING AJUGA REPTANS (LAMIACEAE) IN MOSCOW REGION

• Main Authors: V. N. Godin, N. G. Kuranova, L. R. Akhmetgarieva
• Format: Article
• Language: English
• Published: Penza State University Publishing House 2020-09-01
• Series: Известия высших учебных заведений. Поволжский регион: Естественные науки
• Subjects: ajuga reptans; gynodioecy; flowering

Background. In gynodioecious species, populations of two types of individuals are found – bisexual and female. The morphological and biological characteristics of these two morphs are different. A. reptans is an example of a gynodioecious species. However, information about the flowering biology of both its sexual forms is extremely fragmented. The aim of our research is to study the flowering of A. reptans’ bisexual and female morphs in the Moscow region. Materials and methods. Anthecological observations were made in natural conditions in the Moscow region from 2015 to 2019 according to generally accepted methods. Results. The floral unit of A. reptans is the apical open bracteose thyrsus, which has constituent elements of 3 or 5 flower cymoids. In lateral dichasium, the flower opens acropetally; in the thyrsus, flowers on the axis bloom almost simultaneously. Bisexual flowers of A. reptans are characterized by a weak protandry. Bisexual and pistillate flowers have a long lifespan, surviving for 12–13 days without pollination. A. reptans is characterized by a daily flowering rhythm, with two maximums at 9 a.m and 12 a.m. Bisexual and pistillate flowers open simultaneously. Conclusions. A number of anthecological characters of A. reptans demonstrate that it flowers in spring: the lack of a clear acropetal sequence in the order of flowers blooming in a thyrsus, the long lifespan of both bisexual and pistillate flowers, the opening of flowers during almost all daylight hours, and a fairly short flowering period, due to the need for development in a strictly defined period of vegetation.