Investigating the Phenotypic Plasticity of the Invasive Weed Trianthema portulacastrum L.

Phenotypic plasticity is frequently highlighted as a key factor in plant invasiveness, as it enables invasive species to adapt to diverse, complicated habitats. Trianthema portulacastrum is one of the most common aggressive species that threaten different crops around the world. Phenotypic plasticity in T. portulacastrum was investigated by comparing variation in germination, vegetative macromorphology, photosynthetic pigments, stomatal complexes, and seed micromorphological traits of 35 samples collected from 35 different localities. One-way cluster analysis and principal component analysis (PCA) were used to classify samples into homogeneous groups based on the measured traits. Pairwise statistical comparisons were conducted between the three resulting groups. The phenotypic plasticity index (PI) was calculated and compared among different groups of characters. Results showed that photosynthetic pigments and macromorphological characteristics had the highest PI, followed by seed micromorphology, and then stomatal complex traits, while germination parameters showed the lowest PI. We propose that soil moisture, salinity, and temperature are the most determinative and explanative variables of the variation between the three classified groups. We strongly believe that the phenotypic plasticity of T. portulacastrum will support species abundance and spread even under expected changes in climatic conditions, in contrast to the vulnerable traditional crops.

Micromorphological Characteristics of Fruit Surfaces of Some Usable Species of the Genus Valeriana (Valerianaceae) Among Ukrainian Flora

The micromorphological features of the fruit surfaces of nine species of Ukrainian flora, namely Valeriana tuberosa L., Valeriana tripteris L., Valeriana rossica P. Smirn., Valeriana stolonifera Czern., Valeriana grossheimii Worosch, Valeriana sambucifolia Mikan fil., Valeriana officinalis L. s. str., Valeriana wolgensis Kazak. [ Valeriana officinalis var. nitida (Kreyer) Rostanski], and Valeriana simplicifolia (Rchb.) Kabath, were examined. Depending on the presence and localization of pubescence on the surface of the fruit, three groups of species were distinguished: those with glabrous fruits, those with fruits pubescent only on the adaxial side, and those with fruits pubescent on both sides. Scanning electron microscopy revealed the additional characteristics of the fruits (microsculpture of the fruit surface, shape of cuticular formations on the surface of the outer periclinal walls of epidermal cells and on the surface of hairs, and structure of the stomatal complex), which were useful for the identification of the species. At the supraspecific level, the revealed features of the fruit surfaces somewhat overlapped and could be used to identify series and sections only as additional features. Based on the studied samples from herbarium material (KW), V. officinalis var. nitida was considered synonymous with V. wolgensis since there were no micromorphological differences between their fruits. The detailed micromorphological characteristics of the fruit surfaces of all the studied species can be used for further comparative morphological investigations of different aerial parts to identify stable features independent of geographic and ecological conditions.

Divergent evolutionary trajectories of bryophytes and tracheophytes from a complex common ancestor of land plants

The origin of plants and their colonization of land resulted in the transformation of the terrestrial environment. Here we investigate the evolution of the land plants (embryophytes) and their two main lineages, the tracheophytes (vascular plants) and bryophytes (non vascular plants). We used new fossil calibrations, relative lineage dating implied by horizontal gene transfer, and new phylogenomic methods for mapping gene family origins. Distinct rooting strategies resolve tracheophytes and bryophytes as monophyletic sister groups that diverged in the Cambrian, 515-494 Ma. The embryophyte stem is characterised by a burst of gene innovation, while bryophytes subsequently experienced a no less dramatic episode of reductive genome evolution in which they lost genes associated with the elaboration of vasculature and the stomatal complex. Overall, our analyses confirm that extant tracheophytes and bryophytes are both highly derived; as a result, understanding the origin of land plants requires tracing character evolution across the diversity of modern lineages.

The use of microstructures in the authentication of powdered drug plants

Adulteration and substitution of herbal drugs are trending issues in the herbal industry, posing a serious threat to commercial natural product research. The anatomy of powdered and non-powdered samples of plant species were compared to ascertain their similarities. Air dried powdered leaf samples and unground or intact leaves, flowers and barks of eight medicinal plant species, namely, Vernonia amygdalina, Ocimum gratisimum, Trichilia monadelpha, Bridelia ferruginea, Lophira alata., Alstonia boonei, Dialium guineense and Enantia chlorantha were studied anatomically with the aim of identifying the original plant parts used in the preparation of the drugs. The microscopic studies of leaves of V. amygdalina and O. gratisimum revealed the presence of similar stomatal complex types and trichomes in both ground and unground samples. The anatomy and palynology of T. monadelpha flower revealed that bipolar, inaperturate, monopolar, monoporate, tetracolporate and triporate pollens are present in both the ground and unground samples. The microscopic study of the barks of L. alata, B. ferruginea, A. boonei, D. guineense and E. chlorantha also showed similar cells in ground and unground samples. The anatomical features are, therefore, elucidated for authentication of the originality of the medicinal plants studied.

Tetraploidization Increases the Contents of Functional Metabolites in Cnidium officinale

Cnidium officinale is an important medicinal crop grown in Asia for its pharmacological properties. In this study, tetraploid breeding was conducted to increases the content of medicinal compound and tolerance to the environmental conditions using in vitro shoot culture of C. officinale. For this, we generated tetraploid C. officinale plants using oryzalin, a chromosome doubling agent, and compared the morphological traits, cytological characteristics, and heat stress-responsive gene expression levels between tetraploid and diploid genotypes. Chromosome doubling efficiency was the highest in plantlets treated with 4.0 mg∙L−1 oryzalin for 2 days. Compared with diploids, the plant height of tetraploids was reduced, while the petiole diameter was increased by approximately 39%. The dry matter of tetraploid leaves was significantly higher than that of diploid leaves. Compared with diploids, tetraploids showed higher chloroplast number and stomatal complex size but lower chlorophyll and carotenoid contents. The phenolic content of tetraploid plantlets was significantly higher than that of diploid plantlets. Contents of naringin as well as salicylic acid and gentisic acid, which are strong antioxidant compounds, were dramatically increased upon tetraploidization. Interestingly, liquid chromatography–mass spectrometry (LC–MS) analyses revealed increased levels of senkyunolide F and phthalide in tetraploid roots but not in tetraploid or diploid leaves.

TAXONOMIC STUDY FOR THE NEW RECORD OGASTEMMA PUSILLUM (BORAGINACEAE) IN IRAQ

During the filed survey of 140-160 kilometers region and on both sides of the highway west of Ramadi city in the western desert district of Iraq, and in late spring of 2019, confirmed the recorded of the Ogastemma genus for the first time in Iraq, which was characterized by being a monotypic genus belonging to Boraginaceae family and represented by Ogastemma pusillum. After the identification of the species, which was based on the Flora of the neighboring countries, the species was studied taxonomically. The study worked on describing and photographing all the vegetative and floral parts, anatomy of stem, stomatal complex in leaves, and pollen grains. The plant specimens were preserved under the numbers 60264, 60265 in the Iraqi national herbarium. A morphological study showed that there was uniform indumentum of the epidermis of vegetative organs was appressed-hispid, represented by non-glandular trichomes, medium length of 800-1500 micrometer.

Foliar epidermal anatomy and its taxonomic implications within the family Euphorbiaceae in the Niger Delta Region of Nigeria

Micro-morphological investigations of the foliar epidermal anatomy of seven species of the family Euphorbiaceae: Acalypha hispidia Burm. f., A. wilkesiana Mull. Arg, Euphorbia heterophylla L., E. hirta L., Jatropha curcas L., J. gossypifolia L. and Manihot esculenta Crantz was carried out to assess the systematic relevance of epidermal features, stomata and trichome diversity within the family using light microscope and camera. Members of this family contain many important medicinal herbs and there has been increasing misidentification of species in this family. Leaf micro-morphological characteristics are commonly used in the identification and authentication of plants. Results showed that the stomatal index varied from species to species. Epidermal cell shapes were found to be irregular to polygonal on both surfaces of the species. The epidermal cells possess straight to undulating anticlinal walls but in some few cases exhibited wavy to straight anticlinal walls. The presence of papillae was observed to be a unique character of E. heterophylla among the species studied. The stomatal types observed were Anisocytic, Anomocytic, Diacytic, tetracytic, paracytic, and actinocytic. The stomatal complex was mainly amphistomatic except for A. wilkesiana that was hypostomatic. The hypostomatic character of A. wilkesiana as reported in this paper is the first of such report as previous report found was amphistomatic. Non-glandular, multiseriate uniseriate and in some cases branched trichome types were observed only on both surfaces of A. wilkesiana and E. hirta but absent on all other studied species. This study revealed detailed descriptive micromorphological structures which could serve as a source of information and reference for the taxonomic description, identification and delineation of the species studied.

Maize (Zea mays L.) Nucleoskeletal Proteins Regulate Nuclear Envelope Remodeling and Function in Stomatal Complex Development and Pollen Viability

In eukaryotes, the nuclear envelope (NE) encloses chromatin and separates it from the rest of the cell. The Linker of Nucleoskeleton and Cytoskeleton (LINC) complex physically bridges across the NE, linking nuclear and cytoplasmic components. In plants, these LINC complexes are beginning to be ascribed roles in cellular and nuclear functions, including chromatin organization, regulation of nuclei shape and movement, and cell division. Homologs of core LINC components, KASH and SUN proteins, have previously been identified in maize. Here, we characterized the presumed LINC-associated maize nucleoskeletal proteins NCH1 and NCH2, homologous to members of the plant NMCP/CRWN family, and MKAKU41, homologous to AtKAKU4. All three proteins localized to the nuclear periphery when transiently and heterologously expressed as fluorescent protein fusions in Nicotiana benthamiana. Overexpression of MKAKU41 caused dramatic changes in the organization of the nuclear periphery, including nuclear invaginations that stained positive for non-nucleoplasmic markers of the inner and outer NE membranes, and the ER. The severity of these invaginations was altered by changes in LINC connections and the actin cytoskeleton. In maize, MKAKU41 appeared to share genetic functions with other LINC components, including control of nuclei shape, stomatal complex development, and pollen viability. Overall, our data show that NCH1, NCH2, and MKAKU41 have characteristic properties of LINC-associated plant nucleoskeletal proteins, including interactions with NE components suggestive of functions at the nuclear periphery that impact the overall nuclear architecture.

Maize (Zea mays L.) nucleoskeletal proteins regulate nuclear envelope remodeling and function in stomatal complex development and pollen viability.

ABSTRACTIn eukaryotes, the nuclear envelope (NE) encloses chromatin and separates it from the rest of the cell. The Linker of Nucleoskeleton and Cytoskeleton (LINC) complex physically bridges across the NE, linking nuclear and cytoplasmic components. In plants, these LINC complexes are beginning to be ascribed roles in cellular and nuclear functions, including chromatin organization, regulation of nuclei shape and movement, and cell division. Homologs of core LINC components, KASH and SUN proteins, have previously been identified in maize. Here, we characterized the presumed LINC-associated maize nucleoskeletal proteins NCH1 and NCH2, homologs of members of the plant NMCP/CRWN family, and MKAKU41, homologous to AtKAKU4. All three proteins localized to the nuclear periphery when transiently and heterologously expressed as fluorescent protein fusions in Nicotiana benthamiana. Overexpression of MKAKU41 caused dramatic changes in the organization of the nuclear periphery, including nuclear invaginations that stained positive for non-nucleoplasmic markers of the inner and outer NE, and the ER. The severity of these invaginations was altered by changes in LINC connections and the actin cytoskeleton. In maize, MKAKU41 appeared to share genetic functions with other LINC components, including control of nuclei shape, stomatal complex development, and pollen viability. Overall, our data show that NCH1, NCH2, and MKAKU41 have characteristic properties of LINC-associated plant nucleoskeletal proteins, including interactions with NE components suggestive of functions at the nuclear periphery that impact the overall nuclear architecture.