نشریه رستنیها
سال بیست و پنجم شماره 1 (پیاپی 70، بهار و تابستان 1403)

The genus Myosotis, or “forget-me-not”, has a global distribution in most of the temperate regions of both Northern and Southern hemispheres, a number of its species are used as ornamental plants. In order to clarify the taxonomic relationships of the species of this genus, pollen grains of 14 species were prepared from the T and FAR herbaria and were examined by means of a light microscope (LM) and a scanning electron microscope (SEM). Thirty-one characteristics such as pollen size, shape, surface type and the type, number and size of apertures studied and analyzed by PAST, PCA and IQ-TREE software, and subsequently, phylogenetic trees are drawn. The results indicated that, the species M. ramosissima and M. diminuta and the species M. lithospermifolia 1 and M. sparsiflira found to be closely related to each other as they were clustered together. Moreover, pollen shape dimorphism was identified in the two species of M. lithospermifolia 1 and M. minutiflora while the results of PCA analysis and clustering on the basis of palynological traits placed these species together. The characteristics of the polar axes length in the equatorial view with a light microscopeand diameter of equatorial or polar axes in light microscopy, the relative length of polar axis to equatorial axis of Psedocolpi, and the presence of Ubisch bodies in the polar head of pollen grains have been found to be valuable for the clustering of taxa pollen grains of M. lithospermifolia, M. sparsiflora, Myosotis sp., M. diminuta, M. propinqua, M. olympica, and M. anomala were studied for the first time. The identify key is provided based on examined the pollen grains characters. The non-monad of pollen grains for the first time from Boraginaceae in the form of the diversity of pollen grains of the species M. lithospermifolia 1 was reported.

Arenaria s.l. is the largest genus in Alsineae and one of the morphological complicated genera with a large number of species and endemism in SW Asia with the most concentration in Turkey and Iran, respectively. A recent molecular study demonstrated that, Arenaria s.l. is polyphyletic by including two main groups i.e., Arenaria s.s. and Eremogone. In addition, based on these studies, these two genera belong to Arenarieae and Eremogoneae tribes. Currently, out of 21 taxa related to these two genera that grow in Iran, five species belong to Arenaria and 16 species belong to Eremogone. In the present paper, therefore, the list of these species, the key to identify the genera of the two tribes, namely, Arenarieae and Eremogoneae, along with the key to the species of both genera and the distribution of species in Iran are presented. A new recently described species, namely, Arenaria yazdiana is actually referable to Eremogone due to its similarity to Eremogone persica and E. insignis. Eremogone yazdiana, an endemic species from central mountains of Iran is introduced here as a new combination.

The genus Salvia L. (Lamiaceae) is considered as one of the largest plant genera due to its global distribution and extensive morphological diversity. This research aimed to examine the micromorphological characteristics of the epidermis and stomata in 20 selected species of this genus. Plant samples examined using light microscopy (LM) and scanning electron microscopy (SEM). Quantitative characteristics, including stomatal count and dimension measurements, and qualitative features, such as the arrangement of epidermal cells and the positioning of guard cells, were analyzed. The results showed that, S. virgata and S. syriaca had the highest and lowest stomatal index, and S. viridis and S. officinalis had the longest and shortest stomata, respectively. Significant differences in the appearance of stomata and epidermal cells among the species were noted with stomata in some species being square-shaped. Epidermal cells in some species were ridged while in others were smooth; and all species exhibited diacytic stomatal types. This study demonstrated that, micromorphological characteristics of the epidermis and stomata are useful diagnostic tools for identifying and classifying Salvia species. The use of LM and SEM provided precise information for this purpose, contributing to the improvement of taxonimc methods and plant identification. The observed differences and similarities are likely due to ecological conditions and genetic variations, and understanding these relationships can aid in the development of more exact methods for classifying and identifying species in botanical studies.

Artemisia annua L. (Asteraceae) is a species with high medicinal potential. This study aimed to determine the embryological characteristics of the A. annua with a focus on the development of pollen grains and ovules to help the taxonomic position of this species. Capitulum were studied using light and scanning electron microscopies to describe the floral development. According to the results, the formation of the anther wall was dicotyledonous type and the tapetum layer was multi-nucleated and secretory. The tetrad of microspores were tetragonal and tetrahedral, and mature pollen grains were two-celled, tricolpate. The ovule was of anatropous, unitegmic, and tenuinucellate type. The archesporium was unicellular. T-shaped and linear tetrads of megaspore were observed in megasporogenesis. The micropylar megaspore developed into an eight-nucleate embryo sac with a Polygonum type pattern. Fertilization was of the porogamous type. This species displayed cellular and scant endosperm development. Some embryological features of Asteraceae, Calyceraceae, and G. oodeniaceae are also brought in the present paper. Comparisons revealed embryological features provide obvious evidence for the segregation of these close families. Therefore, based on the study, the authors suggest that systematic studies on this genus and similar genera should not only be done on the thickening of pollen grain surface, but also on the stages of anther and pollen grain development. In addition, embryo sac studies can also reveal hidden systematic differences between different arrays.

Dracocephalum L. (Lamiaceae) contains 10 species in the Flora of Iran. A morphometric analysis based on morphological data was conducted to determine the circumscription of the species complex of D. kotschyi. Morphological characteristics of 13 populations of D. kotschyi, three populations of D. oligadenium, two populations of D. ghahremanii and D. lindbergii, and one population of D. moldavica and D. subcapitatum were examined in 35 quantitative and qualitative traits. To identify the most variable traits among the studied species, factor analysis was performed, revealing that, traits such as the ratio of leaf length to width at the basal leaves, apical and middle leaf shape, presence of hairs on leaves and bracts, and corolla color had the greatest positive impact on species separation. By using Ward's method for cluster analysis, three main clusters were identified in the resulting dendrogram. The first cluster included D. moldavica, which was clearly separated from other species. The second cluster comprised various populations of D. kotschyi (a2) and its closely related species, namely, D. subcapitatum and D. ghahremanii (b2). In this cluster, the distinction of D. ghahremanii from other populations of D. kotschyi and its proximity to D. subcapitatum was confirmed. The third cluster included populations of D. lindbergii (a3) and populations of D. oligadenium, which according to the cluster analysis of morphological traits, were distinguished from D. kotschyi and recognized as an independent species i.e., D. oligadenium. The number of species in Dracocephalum in Iran has therefore, increased to 11.

Mycorrhizal fungi play a crucial role in promoting the growth and yield of agricultural plants, including sugarcane. To evaluate optimal conditions for these fungi and enhance sugarcane yields in Khuzestan Province (Iran), the species and spore density of mycorrhizal fungi were investigated in a research project across eight sugarcane cultivation and industry companies. Combined soil samples were collected from 25 sub-samples of each 64 selected farms and analyzed in the laboratory. The spores were isolated using wet sieving and decanting method followed by sucrose centrifugation used for determination of fungal species and spore density. Meanwhile, factors such as the physicochemical properties of the soil, crop rotation and ratoon age were measured and recorded, and their impact on spore density and sugarcane yield was calculated statistically. A direct and intimate correlation was also discovered between the density of spores in the soil and the yield of sugarcane, with the best outcomes found in well-drained fields (adequate sand), a neutral to slightly alkaline pH, sufficient moisture, and controlled levels of nitrogen, phosphorus, and potassium. On the other hand, crop rotation with plants like alfalfa or wheat which are mycorrhizal dependent as well as allowing fields to go fallow, and using fresh ratoon also led to an increase in the density of mycorrhizal fungi spores and sugarcane yield.

In the framework of collecting and identifying macroscopic fungi of Iran, samples of a coral mushroom were collected and identified as Ramariopsis pulchella (Boud.) Corner (Agaricales, Clavariaceae) based on literature. This is the first report of species from Iran. The characteristics of the identified taxon are as follows: The fruit body consists of coral-shaped branches, pale pink to deep purple; coral branches have regular to irregular sub-branches, double to multiple in length and tip; tips of branches and sub-branches may be sharp or rounded; length of the fruit body is up to 5 cm and the number of branches that determines the width and range of the fruit body is variable; spores spherical to semi-spherical with dimensions of 2.5–3.5 × 3.5–5 µm. Specimen examined: IRAN: Mazandaran Province, Pol-e Sefid, Anarom, saprophyte on soil on the debris of plants and leaves, 6.7.2023, Asef, M.R. (IRAN 18308 F).