Introduction:The risk of drug resistance and the use of medicinal plants in malaria prevention and treatment have led to the search for new antimalarial compounds with natural origin. Methods:In the current study, six extracts with different polarity from aerial parts and rhizomes of Eremostachys macrophylla Montbr. & Auch., were screened for their antimalarial properties by cell-free β-hematin formation assay. Results: Dichloromethane (DCM) extracts of both parts of plant showed significant antimalarial activities with IC50 values of 0.797 ± 0.016 mg/mL in aerial parts and 0.324 ± 0.039 mg/mL in rhizomes compared to positive control (Chloroquine, IC50 = 0.014 ± 0.003 mg/mL, IC90 = 0.163 ± 0.004 mg/mL). Bioactivity-guided fractionation of the most potent part (DCM extract of rhizomes) by vacuum liquid chromatography (VLC) afforded seven fractions. Sixty percent ethyl acetate/n-hexane fraction showed considerable antimalarial activity with IC50 value of 0.047 ± 0.0003 mg/mL. Conclusion: From 6 extracts with different polarity of E. macrophylla,s aerial parts and rhizomes, the DCM extract of both parts were the most active extract in this assay. The preliminary phytochemical study on the VLC fractions of the most potent part persuades us to focus on purifying the active components of these extracts and to conduct further investigation towards in vivo evaluation.

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Astrodaucus orientalis is a weed species in cropping systems and rangelands in Iran. The effects of temperature, light, NaCl concentration, water potential, seed burial depth and crop residue cover were assessed on seed germination and seedling emergence of two populations of A. orientalis from Ardabil (Meshginshahr population) and East Azarbayjan (Tabriz population) provinces of Iran. The A. orientalis populations indicated different responses to environmental factors and burial depth. In the Tabriz population the greatest germination (88.5%) was observed in 20/12°C day/night temperature but in the Meshginshahr population (83.2%) it was obtained in 24/16°C day/night temperature. Over a broad range of light period (10–24 hr light) germination was 74–83%, but it decreased (less than 37%) under 24 hr dark in both A. orientalis populations. With respect to water potential, the C50 parameters were −0.62 and − 0.49 MPa for Tabriz and Meshginshahr populations, respectively. The D50 parameters (the burial depth that caused 50% decrease in emergence) for Tabriz and Meshginshahr populations were 2.42 and 3.13 cm, respectively. Generally, the results showed that emergence of both populations of A. orientalis was delayed as depth of burial increased up to 4 cm and in cropping systems a shallow tillage that locates the seeds to >4 cm of depth in soil could be used in order to suppress seedling emergence. Our findings also could be useful in integrated management of A. orientalis in winter annual crops and rangelands.

Gelasia attariana is described as a new species from northwest of Iran, near the border to Azerbaijan. The new species is morphologically similar to G. cinerea and G. wendelboi, mainly because of sharing caulescent perennial life form, entire lanceolate leaves with 3–7 parallel veins, tomentose indumentum of phyllaries and glabrous achenes without carpopodium, but differs in plant height, indumentum type of stems and leaves, length/width ratio of leaves, leaves color, apex of leaves and length of achenes and pappus. Morphological comparisons and taxonomic relationships of G. attariana with its closely related taxa are discussed. Consistent with morphological data, molecular evidences based on nrDNA ITS sequences confirmed that the new species can be recognized as a distinct taxon from its close relatives. Description, images of living plants and distribution map of the new species are also provided.

Pollen characters of 48 species of Scorzonera s.l. distributed in Iran were investigated by using light and scanning electron microscopy. The pollen grains are isopolar, radially symmetric, generally 3-zonocolporate, rarely 2-colpororate or 4-colporate. The pollen grains are oblate-spheroidal in shape (P/E=0.89 to 0.99) with the polar axes 37.1–58.1 µm and the equatorial axes 38.8–60.6 µm. We adopted the four pollen types recognized by Blackmore based on the number and position of their lacunae. For the first time, some pollen grains of S. longipapposa and S. tortuosissima were shown to have 26 (24+2) lacunae. We compared pollen morphological characters with the findings of the most recent systematic treatment. Type A with 6 lacunae was observed in Takhtajaniantha pusilla and S. parviflora, type B with 18 lacunae in Gelasia, type C with 20 lacunae in Pseudopodospermum and type D with 24 lacunae in Ramaliella, S. renzii and the Podospermum clade (except S. laciniata) in Scorzonera. We also observed 15 or 18 lacunae in S. rupicola. The pollen in Scorzonera appears to evolve toward reduction of spines in S. parviflora, extension of spines in the Podospermum clade, enlargement of the space between ridges and increase in the number of lacunae (S. longipapposa and S. tortuosissima). 26 pollen characters of the examined species were analysed by UPGMA and PCA. Pollen size, spine size, distance between spines, number and arrangement of spines between two equatorail lacunae, exine thickness, spine length/P or E, dimensions of lacunae and polar area were shown to contribute significantly to understanding the morphology of Scorzonera.