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1.
Nicotine treatment of maize seeds at 5.0 and 7.5 mM concentrations caused an increase of 6.2 and 18.7% in amylase activity, respectively. It is being suggested that the positive effect of nicotine on maize is, at least, partially due to increased solubilization of the stored starch through induction of the synthesis or the activity of amylase. 相似文献
2.
Simian immunodeficiency virus RNA is efficiently encapsidated by human immunodeficiency virus type 1 particles. 总被引:16,自引:12,他引:4
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Packaging of retroviral RNA is attained through the specific recognition of a cis-acting encapsidation site (located near the 5' end of the viral RNA) by components of the Gag precursor protein. Human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) are two lentiviruses that lack apparent sequence similarity in their putative encapsidation regions. We used SIV vectors to determine whether HIV-1 particles can recognize the SIV encapsidation site and functionally propagate SIV nucleic acid. SIV nucleic acid was replicated by HIV-1 proteins. Thus, efficient lentivirus pseudotyping can take place at the RNA level. Direct examination of the RNA contents of virus particles indicated that encapsidation of this heterologous RNA is efficient. Characterization of deletion mutants in the untranslated leader region of SIV RNA indicates that only a very short region at the 5' end of the SIV RNA is needed for packaging. Comparison of this region with the corresponding region of HIV-1 reveals that both are marked by secondary structures that are likely to be similar. Thus, it is likely that a similar higher-order RNA structure is required for encapsidation. 相似文献
3.
S. J. H. Rizvi V. Rizvi D. Mukerji S. N. Mathur 《Journal of Plant Growth Regulation》1984,3(1-3):237-244
The effects of some nodular cytokinis, zeatin (Z), zeatin riboside (ZR), N6 (2-isopentenyl) adenine (IPA), and N6 (2-isopentenyI) adenosine (IPAS) on nitrate reductase (E.C 1.9.6.1) activity of root nodules ofPhaseolus mungo were investigated. The cytokinis were also tested for their effect on nitrate uptake by nodules. The results show that IPAS is the most effective of all the four cytokinins tested. Z and IPA, which caused higherin vivo activity than ZR and IPAS, stimulated uptake of nitrate by nodules. The other two (ZR and IPAS) while inhibiting uptake showed greaterin vitro activity than Z and IPA. It may be concluded that some cytokinins, in addition to their direct effects on the enzyme, may increase the substrate availability to it, whereas others may have only an direct effect on the enzyme activation or degradation.Deceased. 相似文献
4.
S1 nuclease hydrolysis and bezoylated naphthoylated DEAE-cellulose (BND-cellulose) chromatography have been used to demonstrate that alkylation of DNA by dimethyl sulfate at neutral pH leads to the production of partially denatured molecules under conditions where no significant depurination occurs. DNA was alkylated with increasing concentrations of the alkylating agent, and subjected to enzymatic degradation and binding to BND cellulose. An increasing degree of DNA hydrolysis and adherence to BND cellulose was seen. On hydroxyapatite chromatography the alkylated DNA still eluted at the position of double-stranded molecules suggesting the presence of partially denatured regions. The presence of salt had a preventive effect on such denaturation. 相似文献
5.
Fungi obtained and isolated from plant material coming in from Afghanistan and intercepted at Quarantine Station, Jamrud have been described. Out of eight species of fungi isolated from different seeds, at least one is not known to occur in Pakistan. Importance of studying seed borne fungi from Quarantine point of view is discussed.
Department of Plant Protection 相似文献
Zusammenfassung Pilze, die von Pflanzenmaterial von Afghanistan erhalten, isoliert und bei der Auarantänestelle Jamrud erwischt worden sind, sind hier beschrieben. Von acht Pilzarten, die von verschiedenen Samen isoliert worden sind, ist eine in Pakistan noch nicht vorgefunden worden. Die Wichtigkeit der Untersuchung von den mit den Pilzen behafteten Samen vom Standpunkt der Quarantäne ist diskutiert.
Department of Plant Protection 相似文献
6.
Aisha Sumbul Rizwan Ali Ansari Rose Rizvi Irshad Mahmood 《Saudi Journal of Biological Sciences》2020,27(12):3634-3640
Stressor (biotic as well as abiotic) generally hijack the plant growth and yield characters in hostile environment leading to poor germination of the plants and yield. Among the plant growth promoting rhizobacteria, Azotobacter spp. (Gram-negative prokaryote) are considered to improve the plant health. Various mechanisms are implicated behind improved plant health in Azotobacter spp. inoculated plants. For example, acceleration of phytohormone like Indole-3-Acetic Acid production, obviation of various stressors, nitrogen fixation, pesticides and oil globules degradation, heavy metals metabolization, etc. are the key characteristics of Azotobacter spp. action. In addition, application of this bacteria has also become helpful in the reclamation of soil suggesting to be a putative agent which can be used in the transformation of virgin land to fertile one. Application of pesticides of chemical origin are being put on suspension mode as the related awareness program is still on. As far as the limitations of this microbe is concerned, commercial level formulations availability is still a great menace. Present review has been aimed to appraise the researchers pertaining to utility of Azotobacter spp. in the amelioration of plant health in sustainable agroecosystem. The article has been written with the target to gather maximum information into single pot so that it could reach to the dedicated researchers. 相似文献
7.
Razia Khan P. Bhawana M. H. Fulekar 《Reviews in Environmental Science and Biotechnology》2013,12(1):75-97
The synthesis of dyes and pigments used in textiles and other industries generate the hazardous wastes. A dye is used to impart color to materials of which it becomes an integral part. The waste generated during the process and operation of the dyes commonly found to contain the inorganic and organic contaminant leading to the hazard to ecosystem and biodiversity causing impact on the environment. The amount of azo dyes concentration present in wastewater varied from lower to higher concentration that lead to color dye effluent causing toxicity to biological ecosystem. The physico-chemical treatment does not remove the color and dye compound concentration. The decolorization of the dye takes place either by adsorption on the microbial biomass or biodegradation by the cells. Bioremediation takes place by anaerobic and/or aerobic process. The anaerobic process converts dye in toxic amino compounds which on further treatment with aerobic reaction convert the intermediate into CO2 biomass and inorganics. In the present review the decolorization and degradation of azo dyes by fungi, algae, yeast and bacteria have been cited along with the anaerobic to aerobic treatment processes. The factors affecting decolorization and biodegradation of azo dye compounds such as pH, temperature, dye concentration, effects of CO2 and Nitrogen, agitation, effect of dye structure, electron donor and enzymes involved in microbial decolorization of azo dyes have been discussed. This paper will have the application for the decolorization and degradation of azo dye compound into environmental friendly compounds. 相似文献
8.
Seed mycoflora associated with wheat was studied on different media with a particular reference to Blotter and potato dextrose agar (PDA) procedures of ISTA. Seed-borne fungi, viz. Fusarium moniliforme, Rhizopus spp., Mucor spp., Alternaria alternata, Aspergillus niger, Aspergillus flavus, Curvularia lunata, Drechslera spp, Alternaria spp. and Penicillium spp., were isolated from the variety HD264. Blotter method was found to be the best media for the isolation of mycoflora whether borne externally or internally. Total number and frequency of occurrence of fungi were recorded. The effect of seed treatment with different chemicals and eco-friendly botanicals was analysed on germination, and growth, better percentage of seed germination and reduction in fungal pathogen were due to biochemical seed treatment. 相似文献
9.
Hamna Saleem Muhammad Arslan Khadeeja Rehman Razia Tahseen Muhammad Afzal 《Saudi Journal of Biological Sciences》2019,26(6):1179-1186
Helophytic plants contribute significantly in phytoremediation of a variety of pollutants due to their physiological or biochemical mechanisms. Phenol, which is reported to have negative/deleterious effects on plant metabolism at concentrations higher than 500 mg/L, remains hard to be removed from the environmental compartments using conventional phytoremediation procedures. The present study aims to investigate the feasibility of using P. australis (a helophytic grass) in combination with three bacterial strains namely Acinetobacter lwofii ACRH76, Bacillus cereus LORH97, and Pseudomonas sp. LCRH90, in a floating treatment wetland (FTW) for the removal of phenol from contaminated water. The strains were screened based on their phenol degrading and plant growth promoting activities. We found that inoculated bacteria were able to colonize in the roots and shoots of P. australis, suggesting their potential role in the successful removal of phenol from the contaminated water. Pseudomonas sp. LCRH90 dominated the bacterial community structure followed by A. lowfii ACRH76 and B. cereus LORH97. The removal rate was significantly high when compared with the individual partners, i.e., plants and bacteria separately. The plant biomass, which was drastically reduced in the presence of phenol, recovered significantly with the inoculation of bacterial consortia. Likewise, highest reduction in chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total organic carbon (TOC) is achieved when both plants and bacteria were employed. The study, therefore, suggests that P. australis in combination with efficient bacteria can be a suitable choice to FTWs for phenol-degradation in water. 相似文献
10.
Razia Sultana Rizwan Arif Manish Rana Saiema Ahmedi Rabiya Mehandi Akrema Nikhat Manzoor Rahisuddin 《Luminescence》2022,37(3):408-421
An oxadiazole derivative 2 was prepared by condensation reaction through cyclization of semicarbazone in the presence of bromine; the structural confirmation was supported by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, Fourier transform-infrared spectroscopy, and liquid chromatography-mass spectrometry. Its sensing ability towards Ni2+ ion was examined showing a binding constant of 1.04 × 105 compared with other suitable metal cations (Ca2+, Co2+, Cr3+, Ag+, Pb2+, Fe3+, Mg2+, and K+) using ultraviolet–visible (UV–vis) and fluorescence spectroscopic studies. The minimum concentration of Ni2+ ions and limit of detection was found to be 9.4 μM. A job's plot gave the binding stoichiometry ratio of oxadiazole derivative 2 vs Ni2+ ions as 2:1. Furthermore, the intercalative binding mode of oxadiazole derivative 2 with calf thymus DNA was supported by ultraviolet–visible (UV–vis) and fluorescent light, viscosity, cyclic voltammetry, time-resolved fluorescence, and circular dichroism measurements. The molecular docking result gave the binding score for oxadiazole derivative 2 as −6.5 kcal/mol, which further confirmed the intercalative interaction. In addition, the antifungal activity of oxadiazole derivative 2 was also screened against several fungal strains (C. albicans, C. glabrata, and C. tropicalis) by broth dilution and disc diffusion methods. In antioxidant studies, the oxadiazole derivative 2 showed potential scavenging activity against 2,2-diphenyl-1-picrylhydrazyl and H2O2 free radicals. 相似文献