Volumes of flow sorted nuclei were analyzed from two highly endopolyploid (diploids with endopolyploid tissues) species (Arabidopsis thaliana and Barbarea stricta), from a less endopolyploid species (Allium cepa) and from two non-endopolyploid species (Chrysanthemum multicolor and Fritillaria uva-vulpis). Intraspecific as well as interspecific comparisons revealed a highly positive correlation (r >0.99) between DNA content and nuclear volume. No significant differences between expected and measured nuclear volumes were noted indicating that chromatin packing is not increased with increasing DNA content in the tested plant species. In epidermis cells of A. thaliana, A. cepa and Ch. multicolor, a lower (r between 0.6 and 0.7) but significant positive correlation between nuclear volume and cell volume was found. This correlation is compatible with the hypothesis that endopolyploidization (EP = consecutive replication cycles not separated by nuclear and cell divisions) might speed up the growth of endopolyploid species and compensate for small genome size.

Plants from the Rosacea family are rich in natural molecules with beneficial biological properties, and they are widely appreciated and used in the food industry, perfumery, and cosmetics. In this review, we are considering Rosa damascena Mill., Rosa alba L., Rosa centifolia L., and Rosa gallica L. as raw materials important for producing commercial products, analyzing and comparing the main biological activities of their essential oils, hydrolates, and extracts. A literature search was performed to find materials describing (i) botanical characteristics; (ii) the phytochemical profile; and (iii) biological properties of the essential oil sand extracts of these so called “old roses” that are cultivated in Bulgaria, Turkey, India, and the Middle East. The information used is from databases PubMed, Science Direct, and Google Scholar. Roses have beneficial healing properties due to their richness of beneficial components, the secondary metabolites as flavonoids (e.g., flavones, flavonols, anthocyanins), fragrant components (essential oils, e.g., monoterpenes, sesquiterpenes), and hydrolysable and condensed tannins. Rose essential oils and extracts with their therapeutic properties—as respiratory antiseptics, anti-inflammatories, mucolytics, expectorants, decongestants, and antioxidants—are able to act as symptomatic prophylactics and drugs, and in this way alleviate dramatic sufferings during severe diseases.

The C‐value paradox remains incompletely resolved after >40 yr and is exemplified by 2,350‐fold variation in genome sizes of flowering plants. The carnivorous Lentibulariaceae genus Genlisea , displaying a 25‐fold range of genome sizes, is a promising subject to study mechanisms and consequences of evolutionary genome size variation. Applying genomic, phylogenetic, and cytogenetic approaches, we uncovered bidirectional genome size evolution within the genus Genlisea . The Genlisea nigrocaulis Steyerm. genome (86 Mbp) has probably shrunk by retroelement silencing and deletion‐biased double‐strand break (DSB) repair, from an ancestral size of 400 to 800 Mbp to become one of the smallest among flowering plants. The G. hispidula Stapf genome has expanded by whole‐genome duplication (WGD) and retrotransposition to 1550 Mbp. Genlisea hispidula became allotetraploid after the split from the G. nigrocaulis clade ∼29 Ma. Genlisea pygmaea A. St.‐Hil. (179 Mbp), a close relative of G. nigrocaulis , proved to be a recent (auto)tetraploid. Our analyses suggest a common ancestor of the genus Genlise a with an intermediate 1C value (400–800 Mbp) and subsequent rapid genome size evolution in opposite directions. Many abundant repeats of the larger genome are absent in the smaller, casting doubt on their functionality for the organism, while recurrent WGD seems to safeguard against the loss of essential elements in the face of genome shrinkage. We cannot identify any consistent differences in habitat or life strategy that correlate with genome size changes, raising the possibility that these changes may be selectively neutral.