The aim of the research was to establish the density of specimens and shoots as well as the reproductive effort of Hydrocharis morsus-ranae during the whole vegetative period in a Polish oxbow lake. The following specimen features were examined: plant diameter, total length, the number of buds, flowers, young fruit, ripe fruit, turions and leaves and also dry total mass, vegetative mass, generative mass, the bud mass, the flower mass, young fruit mass and ripe fruit mass. The density of Hydrocharis morsus-ranae specimens per square metre ranged from 10 to 170 while the density of shoots ranged from 10 to 545. From one square metre overgrown with Hydrocharis morsus-ranae, a maximum of 389 turions, 50 fruit and 4000 seeds are produced. The maximum of reproductive effort is 97.8% of vegetative mass and 2.2% of generative mass in September 2010. The factors which best explain changeability of the Hydrocharis morsusranae population in time are the length and the diameter of the specimens in the population. Fruiting of Hydrocharis morsus-ranae in Poland is higher than in Canada, where it is an invasive taxon. Hydrocharis morsus-ranae is well adapted to the environment in oxbow lakes of the River Vistula and represents the S-R strategy.
Interdisciplinary research was carried out on the impact of climate on the diversity and morphology of Stratiotes aloides L. emergent forms’ phenotype in various latitudes. The objectives of the research were: 1. to determine whether the climate influences the diversity of emergent forms, 2. to determine the diversity of morphological and anatomical traits and chemical composition of S. aloides specimens in Poland and Russia, 3. to examine the content of, and determine the correlation between phenols, phenolic acids, flavonoids, anthocyanins, and tannins in S. aloides. The research demonstrated the substantial diversity of 13 morpho-anatomical traits, and 5 phytochemical traits, both between regions, and individual habitats. Principal Component Analysis (PCA) demonstrated different correlation patterns for the analysed substances between regions characterised by different temperature ranges. S.aloides shows substantial abilities to adapt in terms of structure and physiology to the aquatic environment in various climate zones.
Karol Latowski, Cezary Toma, Magdalena Dąbrowska and Egita Zviedre
Research was carried out on fruits and seeds of Nymphaea and Nuphar taxa collected from Poland, Latvia and Estonia. The aim of the research was to establish diagnostic features which could enable identification of the examined taxa on the basis of the fruit and seed structure and creating a key to identify them. The examined organs were observed through an optic microscope and scanning electron microscope (SEM). New diagnostic features were discovered: spotting of fresh pericarp, the range of the fruit shape coefficient, the colour of the rays in the fruit stigma disc, the thickness of the seed testa, ribs in the seeds, and occurrence of the “puzzle shaped” cells on the surface of the testa. The discovered features were used in the taxonomic characteristics.
Cezary Toma, Andrew N. Efremov and Wioleta Josefowska
The aim of the study was to investigate the morphogenesis of particular developmental stages of T. maritima fruits; from the stage of the bud to the ripe fruit with the use of a scanning electron microscope (SEM), to learn about the morphology and anatomy of ripe fruit, find new diagnostic features of the fruits and verify T. maritima. fruit diagnosis. An optic microscope and Met - Ilo 8 image analyzer were used in the research. In the final part of the research, the occurrence of two diagnostic features was confirmed and seven new diagnostic features of ripe T. maritima fruit were demonstrated. The morphological development of T. maritima fruits is characterized by significant qualitative and quantitative changes of diagnostic value. The range of the changes in the size of T. maritima generative structures is well characterized by the data obtained from the image analyzer. T. maritima fruit diagnosis: dry, indehiscent achene partly syncarpic.