Stem and leaf anatomy of Herniaria L. genus in Turkey

In this study, the stem and leaf anatomy of 11 taxa of the genus Herniaria L. in Turkey from the Caryophyllaceae family of the Paronychioideae subfamily were investigated. Structural features of all taxa were determined and the taxonomic value of the anatomical characters of these taxa was emphasized. Characters that are important for anatomical studies have been identified. The similarities and differences of taxa are revealed. For anatomical studies, from the stem and leaves with microtome sections were taken and paraffin embedding method was applied. For the H. glabra L. taxon, both dry and wet specimens were studied and photographed. For this taxon, measurements were presented in tables and the results were compared. When the cross-sections of the stem are examined; Outermost is a single layered epidermis. Just below is the cortex parenchyma, which consists of an average of 7 layers. H. cinerea DC. subsp. euphratica taxon has the cortex parenchyma is in 5-6 rows. Druze crystals are found in the cortex parenchyma of all taxa. H. pisidica Brummitt taxon has druze crystals both in the cortex and the core region were observed. Under the cortex layer, respectively; sclerenchyma cells and sclerites, phloem, xylem, and pith in the center are exists. Sclereids, which are 1-3 layers in most taxa, H. caucasica Rupr., H. olympica J. Gay and H. amoena Çelebioğlu & Favarger are 1-2 layers, in H. argeae Boiss. is 2 layers. The core region is present in all species. It consists of circular shaped parenchymatic cells and occupies a large area. Stem has collateral vascular bundle for all taxa. In the stem, differences in the number of cortex and sclereites layers are the distinguishing features of the species. When the cross-sections of the leaves are examined; A mesophyll (palisate and sponge parenchyma) layer between the upper and lower epidermis are exists. The number of palisade parenchyma layers is 2-3 in all taxa, and druze crystals are found spread over the mesophyll layer. The mesophyll type is bifacial for all taxa. Sponge parenchyma layer number is 7-8 for 8 taxa, H. amoena and H. hirsuta L. taxa 6-7 layers, H. cinerea subsp. euphratica as 5-6 layers has been identified. The average number of sponge parenchyma layers is 6-8 for all taxa, in H. cinerea subsp. euphratica taxon, the number of layers decreases to 5. In all taxa, stomata were structurally reduced and positioned just below the upper and lower epidermis. In addition, an average of one stoma was found, just below the lower and upper epidermis layers. H. cinerea subsp. euphratica taxon when compared to other taxa in terms of stem and leaf anatomy; when evaluated with regard to the number of cortex layers on the stem, the width of the cortex and the width/length of the xylem being larger and the pith area being calculated more than other annual Herniaria species, the number of sponge parenchyma layers and sponge parenchyma width/height measurements on the leaf are larger than other taxa. As a result of distinctive characters and measurements, it clearly differs from other taxa. In statistical analysis; In normality tests (Kolmogorov Smirnov and Shapiro-Wilk), the 'p' value for each taxon was found to be significant (p < 0.05) and it was revealed that all taxa had different anatomical characters. In the Kruskal-Wallis test; H. cinerea subsp. euphratica and H. pisidica taxa were separated from other taxa. In dendrogram tests with hierarchical clustering, H. cinerea subsp. euphratica taxon is separated from other taxa. As a result of statistical data analysis results and anatomical findings; the systematic position of the H. cinerea subsp. euphratica taxon should be reconsidered. In addition, the numerical data for the H. glabra taxon are similar in the measurements in dry and wet samples. According to this result, it is thought that for anatomy studies, in xeromorphic plants dry herbarium samples can be evaluated.