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1.
Ajania semnanensis (Compositae: Anthemideae), a new species of Ajania from northeast of Iran, Semnan province, is described and illustrated. Ajania semnanensis is a suffruticose perennial growing on rocky and stony slopes of mountains at altitudes of 1500–2800 m a.s.l. Karyological and micromorphological data of the pollen and achenes, as well as a distribution map for the species are provided. The cytotype of the species was found to be diploid (2n = 2x = 18) based on x = 9. The karyotype formula is 2n = 2x = 4M + 6m + 6sm + 2st. Pollen grains of A. semnanensis are prolate‐spheroidal (P/E = 1.1), 3‐zonocolporate and echinate (Anthemis type). The achenes of A. semnanensis are obovate, 1.0–1.5 × 0.5–0.6 mm, light brown, with 4–6 fine and inconspicuous ribs, glabrous, without pappus and with a subbasal carpopodium. The IUCN status of the new species is suggested to be ‘Least Concern’ (LC).  相似文献   
2.
The predatory midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae) is widely used for the control of Aphis spp. in many agricultural systems. We aimed to determine the most suitable host plant for rearing the predatory midges on the prey Aphis gossypii Glover (Hemiptera: Aphididae). Six host plants were selected: cucumber (Cucumis sativus L. cv. Beith Alpha), tomato (Solanum lycopersicum L. cv. Falat111), eggplant (Solanum melongena L. cv. Yummy), pepper (Capsicum annuum L. cv. Bertene) (all Solanaceae), okra [Abelmoschus esculentus (L.) Moensch cv. Clemson Spineless] (Malvaceae), and squash (Cucurbita pepo L. cv. Hybrid rajai) (Cucurbitaceae). Some physical traits (length and density of trichomes) and chemical attributes (nitrogen content) of prey host plants were investigated. The results showed that prey host plants differed significantly in their effect on fitness of the predator. The shortest immature development time (18.07 ± 0.257 days), the longest female adult longevity (7.5 ± 0.18 days), and the highest fecundity (89 eggs/female) of A. aphidimyza were found with squash as prey food. The highest intrinsic rate of increase (0.171 ± 0.009 day?1) and also the shortest mean generation time (22.4 ± 0.32 days) were also obtained when A. aphidimyza fed on A. gossypii reared on squash. Canonical correlation analysis (CCA) approved the correlation between life‐history traits of A. aphidimyza and characteristics of prey host plants. The suitability of squash for rearing A. aphidimyza can be attributed to the higher nitrogen content, longer trichomes, and relatively high density of trichomes, which provided a better environment for A. gossypii and indirectly favored A. aphidimyza. This study showed that squash is the most suitable host plant for rearing A. aphidimyza feeding on A. gossypii.  相似文献   
3.
To evaluate the chemotaxonomic significance of the essential oils of 23 populations of 18 Iranian Ferula species, the chemical composition of the oils was investigated by GC/FID and GC/MS. Altogether, 84 constituents, representing 81.3-99.7% of the total composition of the oils, have been identified. The composition of six species of the genus, i.e., F. oopoda, F. foetida, F. behboudiana, F. diversivittata, F. galbaniflua, and F. hezarlalehzarica, has been reported for the first time. The main constituents identified were α-terpinyl acetate (73.3%), 2,3,4-trimethylthiophene (2; 49.0%), sabinene (75.3%), verbenone (5; 69.4%), β-pinene (59.0-66.3%), and (Z)-β-ocimene (41.7%). Cluster analysis (CA) of the percentage content of the essential oil components of the Ferula species resulted in the characterization of four groups, i.e., taxa containing either i) monoterpene hydrocarbons, ii) oxygenated monoterpenes, iii) organosulfur compounds, or iv) monoterpene, sesquiterpene, and aliphatic hydrocarbons as the principal classes of compounds. Based on the results obtained, the chemical independence of F. hirtella from F. szowitsiana and of F. galbaniflua from F. gummosa at the specific level was concluded and their positions as distinct species were confirmed. The chemotaxonomic relationships among the representatives of the genus Ferula have been discussed in detail.  相似文献   
4.
Mild and efficient oxidation of Hantzsch 1,4-dihydropyridines with sodium periodate catalyzed by Mn(TTP)Cl supported on polystyrene-bound imidazole is reported. This heterogeneous catalyst is of great stability and reusability in the oxidation of 1,4-dihydropyridines with sodium periodate without significant loss of its catalytic activity.  相似文献   
5.
Efficient oxidation of Hantzsch 1,4-dihydropyridines to their corresponding pyridine derivatives with (Bu(4)N)IO(4) catalyzed by tetraphenylporphyrinatomanganese(III) chloride [Mn(TPP)Cl] is reported. This catalytic system shows high efficiency in the oxidation of 1,4-dihydropyridines at room temperature in the presence of imidazole.  相似文献   
6.
The phylogenetic status of the monotypic genus Vavilovia was studied using nrDNA ITS and cpDNA trnL-F and trnS-G regions. The results from the analysis of each dataset and the combined dataset, revealed that Vavilovia is closely related to Pisum, forming a group that is sister to Lathyrus. The molecular data and some morphological and biological characteristics strongly indicate that Vavilovia should be subsumed under Pisum, as Pisum formosum.  相似文献   
7.
In this report, highly efficient oxidative decarboxylation of carboxylic acids with sodium periodate catalyzed by a supported manganese(III) porphyrin is described. In the presence of manganese(III) tetra(4-pyridyl)porphyrin supported on cross-linked chloromethylated polystyrene, [Mn(T4PyP)-CMP], as catalyst, carboxylic acids were converted to their corresponding carbonyl compounds via oxidative decarboxylation with sodium periodate using imidazole as axial ligand. The oxidation of anti-inflammatory drugs such Indomethacin and Ibuprofen was carried out successfully and the decarboxylated products were obtained. This catalyst can be reused several times without loss of its catalytic activity in the oxidation reactions.  相似文献   
8.
An efficient and selective method for methoxymethylation of alcohols and phenols with formaldehyde dimethyl acetal (FDMA) catalyzed by electron deficient tin(IV)tetraphenylporphyrinato trifluoromethanesulfonate, [SnIV(TPP)(OTf)2], is reported. A variety of primary, secondary and tertiary alcohols as well as phenols were converted to their corresponding methoxymethyl ethers with FDMA in the presence of a high-valent tin(IV) porphyrin. This catalyst can be used for selective methoxymethylation of primary, secondary and tertiary alcohols in the presence of phenols or tertiary alcohols. The present method offers several advantages such as short reaction times, high yields, simple procedure, selectivity and applicability for both alcohols and phenols.  相似文献   
9.
The genus Pimpinella L., with about 170–180 species in the world, is one of the largest genera of the family Apiaceae (Umbelliferae). Based on the Flora Iranica treatment, this genus has 25 species in the Iranian plateau, including 19 species in Iran, and six of those (P. tragioides, P. deverroides, P. pastinacifolia, P. anisactis, P. khorasanica and P. khayyamii) are endemic.  相似文献   
10.
Trachyspermum reginei Ajani & Mozzaff. sp. nov., is described and illustrated as a new species from Chaharmahale Bakhtiari province, SW Iran. The new species differs from its closest relative T. confusum, endemic to Afghanistan, mainly by stem, leaf and fruit morphological characters. Its taxonomic relationships with T. podlechii and T. ammi are also discussed. The new species is threatened by different factors and its protection is recommended.  相似文献   
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