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991.
Evaluation of anthelmintic effects of Trianthema (T.) portulacastrum L. (Aizoaceae) whole plant and Musa (M.) paradisiaca L. (Musaceae) leaves against prevalent gastrointestinal worms of sheep was done that may justify their traditional use in veterinary clinical medicine. In vitro anthelmintic activity of the crude aqueous methanolic extract (CAME) of both the plants was determined using mature female Haemonchus (H.) contortus and their eggs in adult motility assay (AMA) and egg hatch test (EHT), respectively. In vivo anthelmintic activity of crude powder (CP) and CAME in increasing doses (1.0-8.0 g kg(-1)) was determined in sheep naturally infected with mixed species of nematodes using fecal egg count reduction test (FECRT) and larval counts. The study design also included untreated as well as treated controls. Fecal egg count reduction and larval counts from coprocultures were performed pre- and post-treatments to assess the anthelmintic activity of the plants. CAME of T. portulacastrum and M. paradisiaca showed a strong in vitro anthelmintic activity and pronounced inhibitory effects on H. contortus egg hatching as observed through AMA and EHT, respectively. Both plants exhibited dose and time dependent anthelmintic effects on live worms as well as egg hatching. M. paradisiaca (LC(50)=2.13 μg mL(-1)) was found to be more potent than T. portulacastrum (LC(50)=2.41 μg mL(-1)) in EHT. However, in vivo, maximum reduction in eggs per gram (EPG) of faeces was recorded as 85.6% and 80.7% with CAME of T. portulacastrum and M. paradisiaca at 8.0 g kg(-1) on 15th day post-treatment, respectively as compared to that of Levamisole (7.5 mg kg(-1)) that caused 97.0% reduction in EPG. All the species of gastrointestinal nematodes (GINs), i.e. Haemonchus contortus, Trichostronglyus spp., Oesophagostomum columbianum and Trichuris ovis which were prevalent, found susceptible (P<0.01) to the different doses of CP and CAME of both plants. The data showed that both T. portulacastrum and M. paradisiaca possess strong anthelmintic activity in vitro and in vivo, thus, justifying their use in the traditional medicine system of Pakistan.  相似文献   
992.
The Upper Swat Canal (USC) System became operational in 1917–1918 in North West Frontier Province (NWFP) of Pakistan. The rehabilitation and modernization of the USC was undertaken with a view to overcoming the shortage of water supplies for irrigation. The water allowance was enhanced from 0.39 to 0.77 Ls−1 ha−1 in the study area. Recently, the operation and management of a secondary canal or ‘distributary’ was transferred to the Farmers Organization (FO). This distributary named ‘Chowki’ offtakes from the Maira Branch of the USC. The cultivable command area (CCA) of this distributary is 4,306 ha and it serves 1,485 beneficiaries. A management committee on Chowki Distributary was formed in 2003. This distributary consists of one main and two minor channels having twenty-eight direct outlets. The Simulation of Irrigation Canal (SIC) hydrodynamic model was used to evaluate the flexibility of Chowki Distributary. The model was calibrated at 100, 80 and 70% of the design discharge (Q d) and it was validated at 90, 85 and 60% of the design discharge. The observed and simulated water levels were in close agreement with each other for the calibration and validation periods. The statistical analysis and paired t-test indicate that the model results are not statistically different from the measured values at 1% significance level. The simulated results of the SIC model were applied to studying flexibility of the outlet structures along the Chowki Distributary. The flexibility analysis demonstrates that poor performance is inbuilt into the system due to inadequate control over the accuracy of the crest setting during the construction of the outlets.  相似文献   
993.
Gibberellins production by soil fungi received little attention, although substantial work has been carried out on other growth promoting aspects of soil borne fungi. We investigated gibberellins production and growth promoting capacity of a novel fungal strain of Neosartorya, which was isolated from the roots of Chinese cabbage (Bassica rapa L. ssp. pekinensis). Fungal culture filtrates (CF) obtained from pure cultures of 16 endophytic fungi were bioassayed on Waito-C, in order to investigate plant growth promoting capacity of these fungi. The fungal isolate CC-8 induced maximum shoot length of Waito-C (13.0 cm) as compared to control treatments. In a separate experiment, the CF of fungus CC-8 significantly promoted plant length and biomass of Chinese cabbage. The fungal CF also increased endogenous bioactive GA1 and GA4 contents of Chinese cabbage. Gibberellin analysis of CF of CC-8 showed presence of both physiologically active and non active gibberellins in higher concentrations (GA1, 1.42 ng/ml; GA3, 5.93 ng/ml; GA4, 11.36 ng/ml; GA7, 3.25 ng/ml; GA9, 0.79 ng/ml; GA15, 1.18 ng/ml). The culture filtrate of CC-8 produced higher amounts of GA3, GA4, GA7 and GA9 than wild type Fusarium fujikuroi, a well known gibberellins producing fungus. The fungal isolate CC-8 was later identified as a new strain of Neosartorya species on the basis of traditional and advance molecular techniques.  相似文献   
994.
Plantago major L. (common plantain) has been used in folk medicine all over the world, mainly for the healing of wounds. This species already has a high market demand in Asia, and attempts to domesticate P. major as a medicinal crop in horticulture are emerging also in Europe. Both polysaccharides and polyphenols have been proposed to have bioactive effects. In this study, major phenols were analysed in leaves, flower stalks and seeds of P. major plants from five homogenous offspring families, as verified by DNA-marker analysis. Furthermore, leaves were harvested and dried at different temperatures. The contents of plantamajoside, verbascoside and a hitherto unidentified compound, P1, differed greatly between plant organs. Degradation of leaf polyphenols increased with an increase in drying temperature, and consequently, freeze-drying resulted in the highest content of phenols. Thus it is important to select plant material of a suitable organ or combination of organs, and to use the lowest possible drying temperature to obtain a high content of a specific phenolic compound in P. major.  相似文献   
995.
The distribution and composition of extracellular matrix (ECM) of the spleen in two species of fruit bats, namely Cynopterus titthaecheilus and Rousettus leschenaultii, were examined by histochemistry and immunohistochemistry. Reticular fibres accompanied by laminin were identified to make up the splenic stromal network. Types I and III collagen were identified in various spleen compartments with varying intensities. Thin and short elastin fibres were scattered in several parts of the spleen. Visualization of the ECM of the spleen can better demonstrate spleen compartmentalization. The alleged vascular space structure in the fruit bats spleen was the sinus structure that was strengthened by the presence of reticular fibres that limit the sinus basement membrane. The present study identified periellipsoidal lymphoid sheath (PELS)-like structure in fruit bats spleen that had never been identified in mammals before. In addition to describing the structure, this study highlighted the variations in ECM composition of the spleen between species that can provide new insight into the phylogenetic study of spleen morphology.  相似文献   
996.
Soil organic carbon(SOC) and nitrogen(N) mineralization are important biogeochemical processes associated with soil fertility. These processes are influenced by physically, chemically, and biologically stabilized SOC fractions, the mechanisms of which are not well known. The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included: i) no fertilizer control(CK); ii)...  相似文献   
997.
Maximizing nitrogen use efficiency (NUE) involves synchronizing the interplay between nitrogen preferential crops and the nitrogen transformation pathways of soil. Biochar may benefit specific N-preference crops in relatively unsuitable soil environments; however, experimental data are lacking. This study tested eight treatments, consisting of four nitrogen treatments (N0 = control; N1 = NH4Cl; N2 = NaNO3; and N3 = 1:1 ratio of NH4+ and NO3) each with biochar applied at 0% or 2% (w/w). The results show that biochar and/or nitrogen application enhanced maize seedling biomass and NO3-based fertilizer resulted in higher seedling biomass than NH4+-based fertilizer. With the application of biochar and NH4+-based fertilizer, maize seedling biomass increased and soil NH4+-N content was significantly reduced compared with NH4Cl sole application. Correlation analysis and redundancy analysis revealed that SOC content and inorganic nitrogen content were the main factors influencing maize growth and N absorption. Biochar with or without nitrogen fertilizer (except N1 treatment) significantly increased β-1,4-glucosidase (BG) activity. Co-application treatments also resulted in higher vector length, an indicator of C limitation—the increment might add to the risk of microbial C limitation. The activity of ammonia monooxygenase (AMO), a key enzyme in nitrification, decreased with the co-application of biochar and nitrogen, suggesting the alteration of nitrogen transformation.  相似文献   
998.
Manipulation of flowering time to develop cultivars with desired maturity dates is fundamental in plant breeding.It is desirable to generate polyploid rapeseed(Brassica napus L.)germplasm with varying flowering time controlled by a few genes.In the present study,Bna SVP,a rapeseed homolog of the Arabidopsis SVP(Short Vegetative Phase)gene,was characterized and a set of mutants was developed using a CRISPR/Cas9-based gene-editing tool.A single construct targeting multiple sites was successfully applied to precisely mutate four copies of Bna SVP.The induced mutations in these copies were stably transmitted to subsequent generations.Homozygous mutants with loss-of-function alleles and free transgenic elements were generated across the four Bna SVP homologs.All mutant T1lines tested in two environments(summer and winter growing seasons)showed early-flowering phenotypes.The decrease in flowering time was correlated with the number of mutated Bna SVP alleles.The quadruple mutants showed the shortest flowering time,with a mean decrease of 40.6%–50.7%in length relative to the wild type under the two growth conditions.Our study demonstrates the quantitative involvement of Bna SVP copies in the regulation of flowering time and provides valuable resources for rapeseed breeding.  相似文献   
999.
The fall armyworm Spodoptera frugiperda is a lepidopteran pest that can damage and destroy a wide variety of crops. It is widely present in the Americans and has been invasive in Africa since 2016. Larvae of Sfrugiperda were found for the first time in four rural farms on maize plants (Zea mays) located in Tafas town (Dara’a Governorate, in the south‐west of Syria) in November 2020. Infested maize showed the typical damage symptoms caused by Sfrugiperda. Furthermore, morphological identification of larvae based on standard parameters of larvae confirmed the identity of the pest as fall armyworm. Considering the recent introduction of the pest into the EPPO region, it could be concluded that the pest probably entered Syria through natural spread (active flight and via wind currents) from Jordan, which borders Syria in the southern part and where the pest was found very recently.  相似文献   
1000.
European Journal of Plant Pathology - The ongoing global spread of Tomato yellow leaf curl virus (TYLCV) poses an endemic threat to tomato production in all tropical and sub-tropical regions of the...  相似文献   
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