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Appropriate knowledge of the parental cultivars is a pre-requisite for a successful breeding program. This study characterized fruit yield, quality attributes, and molecular variations of ten tomato cultivars during three consecutive generations under greenhouse conditions. Peto 86, Castle Rock, and Red Star cultivars showed the highest fruit yield (kg/plant), total phenolic compounds (TPC), and sap acidity. Principal component analysis categorized the evaluated fruit yield into three groups based on their quality attributes. A robust positive correlation appeared among traits inside each group. A positive correlation was likewise noticed between the first and the second groups. However, a negative correlation was detected between the first, the second and the third group. Molecular profiling, using seven inter-simple sequence repeat (ISSR) primers, produced 60 loci, including 49 polymorphic loci. The molecular analysis also pinpointed the highest genetic similarity (0.92) between P73 and Moneymaker, while the lowest genetic similarity (0.46) was observed between Castle Rock and Moneymaker. The cultivars P73 and Moneymaker showed the lowest genetic distance (2.24), while the highest genetic distance (5.92) was observed between Super Marmand and Peto86, on the one hand, and between Castle Rock and Moneymaker, on the other hand. The chemical analysis of fruit sap indicated the highest levels of TPC, total flavonoids, anthocyanin, ascorbic acid and total soluble solids in Peto 86 and Castle Rock cultivars. Phylogeny analysis of tomato cultivars based on morphological and molecular attributes indicated four distinct clades. Peto 86, Castle Rock, and Red star cultivars can be recommended for the tomato hybridization breeding programs in the future, with other tomato cultivars as potentially high-yielding parents.  相似文献   
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Effects of the cytochrome P450 inhibitor piperonyl butoxide and the P-glycoprotein inhibitor verapamil on the efficacy of ivermectin and thiabendazole were studied in vitro in susceptible and resistant isolates of the cattle parasitic nematodes Cooperia oncophora and Ostertagia ostertagi. The effects of combined use of drug and piperonyl butoxide/verapamil, respectively, were investigated in the Egg Hatch Assay, the Larval Development Assay and the Larval Migration Inhibition Assay. The effects of piperonyl butoxide and verapamil as inhibitors of thiabendazole and ivermectin responses were particularly marked for larval development, where both inhibitors were able to completely eliminate all differences between susceptible and resistant isolates. Even the lowest concentrations of anthelmintics used in combination with inhibitors caused complete inhibition of development. Differences and/or similarities among responses in different isolates were only obtained in the two other assays: in the Egg Hatch Assay piperonyl butoxide caused a shift in concentration–response curves obtained with thiabendazole to the left for all isolates tested, changing relative differences between isolates. In contrast, an effect of verapamil in the Egg Hatch Assay was only apparent for benzimidazole-resistant isolates. In the Larval Migration Inhibition Assay only ivermectin was tested and piperonyl butoxide shifted the concentration–response curves for all isolates to the left, again eliminating differences in EC50 values between susceptible and resistant isolates. This was not the case using verapamil as an inhibitor, where curves for both susceptible and benzimidazole-resistant isolates shifted to the left in Ostertagia isolates. In Cooperia the picture was more complex with ivermectin-resistant isolates showing a larger shift than the susceptible isolate. Single nucleotide polymorphisms in the β-tubulin isotype 1 gene were investigated. Significantly increased frequencies of resistance-associated alleles were observed for the codons 167 and 200 in one benzimidazole-resistant isolate but not in an isolate selected for benzimidazole resistance at an early stage of selection.  相似文献   
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Diphtheria toxin (DT) is a potent toxin produced by the so-called diphtheria group which includes Corynebacterium diphtheriae (C. diphtheriae), Corynebacterium ulcerans (C. ulcerans), and Corynebacterium pseudotuberculosis (C. pseudotuberculosis). The present investigation is aimed to study in detail the production of DT by C. pseudotuberculosis. Twenty isolates were obtained from sheep diseased with caseous lymphadenitis (CLA) and twenty-six isolates were obtained from 26 buffaloes diseased with oedematous skin disease (OSD). All isolates were identified by standard microbiological and DT production was assayed serologically by modified Elek test and immunoblotting. All sheep isolates were nitrate negative, failed to hydrolyze starch and could not produce DT, while all buffalo isolates (biotype II) revealed positive results and a specific band of 62 kDa, specific to DT, was resulted in all concentrated cell fractions (CF), but was absent from non-toxigenic biotype I isolates. At the same time, another band of 31 kDa specific to the PLD gene was obtained with all isolates of biotype I and II. Moreover, all isolates showed positive synergistic hemolytic activity and antagonistic hemolysis with β-hemolytic Staphylococci. The obtained results also indicated that C. pseudotuberculosis could be classified into two strains; non-toxigenic biotype I strain, which failed to produce DT as well as being negative to nitrate and starch hydrolysis, and toxigenic biotype II strain, which can reduce nitrate, hydrolyze starch as well as produce DT.  相似文献   
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Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds were evaluated. The cytotoxic assays for HCT116, HePG2 and MCF7 showed a significant IC50: 54.7 and 76.2 µg/mL of non-polar fraction “n-hexane” against HCT116 and HePG2, respectively. Antibacterial results revealed that plant fractions exhibited significant potential against the tested pathogens than the total extract where n-butanol and ethyl acetate fractions showed significant antibacterial activity (P < 0.05) against tested bacterial strains. Isolation and structure determination of compounds from n-hexane and n-butanol fractions were performed. From n-hexane fraction, 29-nor-cycloartanol (1), lanost-8-en-3-ol (2a), cycloartanol (2b) and kampferol-3,4'-dimethyl ether (3) were isolated and structurally identified, along with 24 compounds were tentatively identified by GC–MS. From the polar n-butanol fraction, 4-O-β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4), 4-O-α-L-rhamnosyl-(1 → 6)-β-D-glucopyranosyl-2-hydroxy-6methoxy-acetophenone (5), quercetin-3-O-glucopyranoside (6) and isoorientin (7) were assigned. Structures of the obtained compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. Except compounds 1 and 5, all reported compounds announced antibacterial efficiency. Compound 2 showed selectively the highest activity against Enterococcus faecalis (22 ± 0.13 mm), meanwhile 4-O-β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4) showed broadly the highest antibacterial activity with MIC of 1.15–1.88 mg/mL against the test Gram-positive and Gram-negative bacteria. Cytotoxic assays indicated that kampferol-3,4'-dimethyl ether (3) exhibited the highest activity with matching IC50 values to doxorubicin; 111.46, 42.67 and 44.90 µM against HCT116, HePG2 and MCF7, respectively, however, it is toxic on retina normal cell line RPE1.  相似文献   
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This present study includes twelve species that represent the Ficus genus, namely; aspera, carica, tinctoria subsp. gibbosa, hirta, hispida, neriifolia, palmata, pumila, racemosa, septica, sur, and sycomorus, belonging to the Moraceae family. The species samples were collected from various locations in Egypt. The study focused on the anatomical and molecular characteristics of mature foliage leaves. Since the identification and classification of taxa are highly dependent on the anatomical features of leaves, the anatomical characteristics were recorded in the form of a comparison between the examined plants in the data matrix. This study aims to contribute to the identification of the studied species based on the anatomical details of the matured leaves. Anatomical characterization includes the variations in upper and lower epidermal layers that are covered by a thin or thick cuticle; the number of palisade and spongy layers; crystals; secretory elements; lithocysts; the midrib zone has parenchyma associated with mechanical tissue, vascular system, and investigation of trichomes; on the other hand, in the current study, the phylogenetic analysis was conducted by using the ITS and 5.8 S sequences. From the analysis of all the available data, it could be stated that there is an overall agreement with the anatomical character dendrogram.  相似文献   
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A three years survey and monitoring studies (2013–2014–2015) were carried out through 4 regions of north Tunisia in order to follow the evolution of the distribution, the frequency of occurrence and damage caused by the Hessian fly Mayetiola destructor (Say) to bread wheat (Triticum aestivum L.) and durum wheat (Triticum durum Desf). Moreover, the effectiveness of resistance genes H3, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H22, H23, H25 and H26 to protect wheat from Hessian fly attack was assessed in natural field and under controlled laboratory conditions at INRAT-Kef Station. Results showed that Hessian fly was detected in 60.33% and 51.5% of all sampled durum and bread wheat fields, respectively. This pest was more frequent with a higher percentage of infestation in semi-arid regions. Indeed, during 2013, infestation rate attained 12.39% in Kef region against 0.9% registered in Bizerte region. In order to update information about the annual number of generations, we surveyed the population dynamic of Hessian fly in Kef region. Three generations of the fly were counted annually on wheat, with two complete and one incomplete generation. This insect affects host plant growth at different developmental stages. Plant height was the most affected parameter followed by shoot dry weight and tiller number. Field investigations on host resistance revealed that among the 16 tested resistance genes, and only three were strictly effective (H22, H25 and H26). The resistance genes H5, H9, H13 and H9H13 have also conferred high levels of protection against Hessian fly. This work indicated that H22, H25 and H26 genes could be incorporated into Tunisian wheat varieties and released to farmers to manage the threat due to Hessian fly attacks.  相似文献   
9.
Determination of the somaclonal variation of in vitro-propagated plants is crucial to determine the appropriate micropropagation protocol and growth regulators for commercial scale multiplication. In this research, nine multiplication media (MM) augmented with different concentrations of 6-benzyl adenine (BA), Kinetin (Kin), and Thidiazuron (TDZ), Three rooting media (RM) supplemented with three levels of α-naphthalene acetic acid (NAA) and three types of soil mixtures (v/v); Coco peat/Vermiculite/Sand (CVS), Peat moss/Perlite/Sand (PPS) and Peat moss/Perlite (PP) were used in the micropropagation protocol of daylily plants. MM2 showed the maximum shoot length and the number of leaves, while MM9 showed the maximum number of shoots. The RM1 showed the maximum root length and the number of roots. During acclimatization, CVS, PPS, and PP soil mixture showed similar performance except the CVS mixture showed lower performance regarding plant height and diameter. The genetic fidelity of micropropagated plants was evaluated using Start Codon Targeted (SCoT) Markers. Six SCoT primers amplified 51 scorable bands with an approximate range from 146 bp to 1598 bp size. Thirty one out of 51 loci were presented in the mother plants. 40 loci were polymorphic, 11 were monomorphic and 7 were unique. The amplification patterns of the micropropagated plants demonstrated genetic integrity to the mother plant ranging from 84.32 to 47.06 and somaclonal variations ranging from 52.94 with 5 mg/l BA pathway to 15.68 with 1mg/l TDZ pathway, thus demonstrating that the homogeneity and the variation of the micropropagated plants affected by the type and the quantity of the plant growth regulator used during multiplication subcultures. This research can be successfully used for other ornamental and medicinal plants’ bulk multiplication, germplasm conservation, and future genetic improvement.  相似文献   
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