Gentiana asclepiadea L. from Two High Mountainous Habitats: Inter- and Intrapopulation Variability Based on Species’ Phytochemistry

Natural populations of Gentiana asclepiadea L., located at two mountainous sites, were HPLC-analyzed regarding the contents of six representative secondary metabolites. The contents of swertiamarin (SWM), gentiopicrin (GP), sweroside (SWZ), mangiferin (MGF), isoorientin (ISOOR), and isovitexin (ISOV) were determined in six populations (three per study site), and separately for aboveground and belowground plant parts. PCA showed a clear separation of four groups according to the contents of the analyzed secondary metabolites. Out of six analyzed compounds, five were present in all samples and only one (SWZ) was found in Golija populations (belowground parts) but not in Vlasina populations, and its presence can be indicative of the geolocation of populations. Clear separation of groups was mostly affected by the different contents of chemical compounds in plant parts (aboveground versus belowground) and by the differences related to population origin (higher content of SWM and GP in belowground parts of individuals from Vlasina populations and higher content of MGF and ISOOR of individuals from Golija populations). The results of this study contribute to the spatiochemical profiling of G. asclepiadea populations and a better understanding of inter- and intrapopulation variability of pharmacologically important compounds.

The Population Ecology of Gentiana oschtenica (Kusn.) Woronow in the Highlands of the Republic of Adygea

The article presents the results of the study of the ecology of Gentiana oschtenica by population-ontogenetic methods. Most coenopopulations have normal ontogenetic right-sided spectra with a maximum on the group of virginile or generative individuals. The state of coenopopulations is pessimal. The level of the ecological and geographical variability is significantly lower than the level of the intrapopulation variability. The data on the variability of morpho-parameters support the species independence of G. oschtenica.

Intrapopulation variability for male gametophyte traits in the tomato F3 and F4 offspring derived from high temperature resistant F2 recombinants

Relevance Identification of forms resistant to thermal stress is important not only at the stage of search, but also later in the selection process. Methods The paper presents the results obtained during the studies on the variability of tomato male gametophyte traits (pollen viability, pollen tube length, pollen resistance and resistance along pollen tubes) in the hybrid F2, F3 and F4 offspring derived from different crossing combinations strongly resistant to high temperature stress (8 hybrid combinations). Results Recombination differences expressed in the values of average variation per family (S2) have been found in the F2 populations segregated for a complex of pollen traits, which made it possible to isolate transgressive recombinants from different hybrid combinations, to produce seeds from them and to further perform selection cycles in F3. It has been found that high intrapopulation variability of male gametophyte traits is preserved in F3 and F4 offspring, which reflects the response of their genotypes to high temperature. The offspring derived from the best F2 recombinants has been shown to not preserve a high level of resistance in F3 and F4. As for the pollen heat resistance, the actual shift of the trait values in F3 in relation to F2 made 0.92, while it made 0.65 in F4 in relation to F2. The shift of the values in the dynamics of the F2, F3 and F4 generations from different hybrid combinations was somewhat higher for the resistance of pollen tubes making 0.99 (F3/F2) and 1.15 (F4/F2). The most pronounced positive shift towards high values in F3 and F4 in relation to F2 was recorded just in three combinations, L7 x L305, L7 x cv. Ceros, L7 x cv. Lider (R – 1.91; 1.29 and 1.08, respectively). High variability in the populations of F4 offspring is observed for quantitative traits, as well, namely, inflorescence number per plant, flower number per inflorescence, the number of set fruits per inflorescence and seed number in fruits. The differences in the offspring diversity found during estimation of the segregating F2 populations derived from different crossing combinations for the variability range have not been confirmed in F3 and F4.