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71.
72.
Lamia Sakouhi Sondès Rahoui Marouane Ben Massoud Shintaro Munemasa Ezzeddine EL Ferjani Yoshiyuki Murata Abdelilah Chaoui 《Journal of Plant Growth Regulation》2016,35(4):1064-1073
Impact of exogenous calcium and ethylene glycol tetraacetic acid (EGTA) supplement on chickpea (Cicer arietinum L.) germinating seeds exposed to cadmium stress for 6 days was studied. Ca and EGTA late treatment (3 days) alleviated growth inhibition and decreased Cd accumulation as well as lipid peroxidation and protein carbonylation in both root and shoot cells. Exogenous effector application relieved Cd-induced cell death which was associated with a constant level of ATP, which was considered as an apoptotic-like process. Redox balance was examined through the study of the redox state of pyridine nucleotide couples NAD+/NADH and NADP+/NADPH as well as their related oxidative [NAD(P)H-oxidase] and dehydrogenase (glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and malate dehydrogenase) enzyme activities. The present research illustrated an ameliorative effect of Ca and EGTA on growth of Cd-exposed chickpea seedlings that occurs through the protection of sensitive cell sites from Cd-induced oxidation, namely membrane lipids and proteins, rather than the improvement of recycling capabilities of the cellular reducing power. 相似文献
73.
Crown-gall tumor initiation by Agrobacterium tumefaciens (SMITHand TOWN.) CONN, strain B6, on Phaseolus vulgaris L. var. "Pinto"was found to be sensitive to the addition of various salts tothe freshly inoculated primary leaves. Calcium, magnesium, zincand ammonium sulfates, cobalt and nickel chlorides and potassiumnitrate increased the number of tumors on inoculated leavesby 100 to 200 percent. Maximal promotions were obtained at concentrationsof 107 to 105 M with all of these salts exceptpotassium nitrate which was most active at 102M. Sodium,potassium, calcium, magnesium and aluminum chlorides, and sodium,potassium and nickel sulfates had little or no effect on tumorinitiation. The combination of sodium sulfate with magnesiumchloride gave promotions comparable to those obtained with magnesiumsulfate, indicating that both the magnesium and sulfate ionswere necessary for the promotion obtained with this latter salt.Combining any two of the active salts at their optimum concentrationsfor promotion resulted in a reciprocal inhibition of the promotionobtained with either salt alone, suggesting these salts to beactive by different and potentially antagonistic mechanisms.The possible nature of these promotions is discussed, but theyremain too obscure to warrant a specific proposal for theirmode of action.
1Present adress: Department of Botany, University of Khartoum,Khartoum, Sudan. 相似文献
74.
This study demonstrates that Pleistophora schubergi Zwölfer, 1927, a microsporidium originally isolated from the midgut epithelium of Nygmia phaeorrhoea Don (Euproctis chrysorrhoea L.) and Porthetria dispar L., and subsequently reported in several other insects including the spruce budworm, Choristoneura fumiferana (the host used in this investigation), does not belong in the genus Pleistophora Gurley, 1893. Pleistophora schubergi lacks the major features that are characteristic of Pleistophora typicalis, the type species of this genus. A comparison of ultrastructural observations reported for the type species of the genus Pleistophora, P. typicalis, and our observations of P. schubergi revealed significant differences. A thick (0.5 μm) amorphous coat, derived from parasite secretions and deposited external to the parasite plasmalemma, surrounds all developmental stages in P. typicalis. Double membranes, derived from host rough endoplasmic reticulum cisternae encircle the parasite plasmalemma of all developmental stages in P. schubergi. The sporophorous vesicle encases the spores in P. typicalis, and originates from the parasite-secreted coat that is present around meronts. In P. schubergi, the host endoplasmic reticulum cisternae form the envelope that surrounds the meronts. Moreover, the sporophorous vesicle envelope in P. typicalis persists around groups of spores, while in P. schubergi this envelope breaks easily to release the spores in the host cytoplasm. By comparing the characteristics of the microsporidium found in the spruce budworm with those of the recently created polysporous genera that sporulate within a vesicle, we found that P. schubergi does belong in the new genus Endoreticulatus Brooks et al. 1988, and consequently rename it Endoreticulatus schubergi (Zwölfer, 1927) n. comb. 相似文献
75.
KERMODE ALLISON R.; GIFFORD DAVID J.; THAKORE EL A; BEWLEY J. DEREK 《Journal of experimental botany》1985,36(5):792-799
Proteins in the soluble and insoluble fractions, extracted frommature castor bean cv. Hale seed cotyledons, differ quantitativelyand qualitatively from their counterparts extracted from theendosperm. The soluble fraction contains no glycoproteins, andthe lectins RCA1 and ricin D are absent. While the insolubleproteins are electrophoretically and immunologically similarto those in the endosperm, they do not form the 100 kD subunitdimers which characterize some of the endosperm insoluble crystalloidproteins. Rapid rates of deposition of all of the soluble andinsoluble proteins present in the mature seed cotyledons commences3035 d after pollination (DAP) and continues until 45DAP. These proteins are mobilized rapidly beginning 12d after seed imbibition and this coincides with an increasein specific activity, in the cotyledons, of two aminopeptidasesand a carboxypeptidase. The soluble and insoluble proteins inthe cotyledons of the mature seed probably function as storageproteins and support the growth of the germinated seed priorto the mobilization of the major protein storage reserves ofthe endosperm. Key words: Ricinus communis, Castor bean, Hale cultivar, Cotyledon, Storage protein, Seed development, Seed germination 相似文献
76.
Mazhar Ali Nasir Masood Hafiz Muhammad Rashad Javeed Ibrahim Al-Ashkar Khalid F. Almutairi Liyun Liu Muhammad Aqeel Sarwar Karthika Rajendran Ayman EL Sabagh 《Phyton》2022,91(10):2235-2248
Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity,
and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical
properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite
species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis
that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles
were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC)
and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that
EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were
transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed
that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the
termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme
indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings
revealed that transportation preferences were observed among the four termite species. In conclusion, the current
study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these
have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes
heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was
necessary to conduct additional research into the effect of temperature on the transportation process. 相似文献
77.
Background
Many algorithms have been developed for deciphering the tandem mass spectrometry (MS) data sets. They can be essentially clustered into two classes. The first performs searches on theoretical mass spectrum database, while the second based itself on de novo sequencing from raw mass spectrometry data. It was noted that the quality of mass spectra affects significantly the protein identification processes in both instances. This prompted the authors to explore ways to measure the quality of MS data sets before subjecting them to the protein identification algorithms, thus allowing for more meaningful searches and increased confidence level of proteins identified. 相似文献78.
79.
Micelle‐enhanced spectrofluorimetric method for determination of lacidipine in tablet form; application to content uniformity testing
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A highly sensitive, simple and rapid spectrofluorimetric method was developed for the determination of lacidipine (LCP) in tablets. The proposed method is based on the investigation of the fluorescence spectral behavior of LCP in both sodium dodecyl sulphate (SDS) and the tween‐80 micellar system. In aqueous solutions of acetate buffer (pH 4.5), the fluorescence intensities of LCP were greatly enhanced (ca. 2.4 and 4.3 folds) in the presence of either SDS or tween‐80, respectively. The fluorescence intensity was measured at 444 nm after excitation at 277 nm using either SDS or tween‐80 as a surfactant. The fluorescence–concentration plots were rectilinear over the ranges of 50.0–500.0 ng/ml and 5.0–200.0 ng/ml with lower detection limits of 5.11 and 2.06 ng/ml and lower quantification limits of 17 and 6.87 ng/ml using SDS and tween‐80, respectively. The method was successfully applied to the analysis of LCP in commercial tablets and the results were in good agreement with those obtained with the comparison method. Furthermore, content uniformity testing of pharmaceutical tablets was also conducted. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
80.
RENATA JACH ELŻBIETA MACHANIEC ALFRED UCHMAN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(3):342-355
Jach, R., Machaniec, E. & Uchman, A. 2011: The trace fossil Nummipera eocenica from the Tatra Mountains, Poland: morphology and palaeoenvironmental implications. Lethaia, Vol. 45, pp. 342–355. The tubular trace fossil Nummipera eocenica Hölder 1989 occurs in a single stratigraphical horizon in Eocene nummulitic limestones of the Tatra Mountains, Poland. The wall of N. eocenica is built of Discocyclina and Nummulities (larger foraminifera) tests, very rarely of the Ditrupa (Polychaeta) tube fragments, bivalve shell fragments, echinoid spines and coralline algae. Morphotype are distinguished on the basis of wall composition and structure. Morphotype A is dominated by fusiform Discocyclina tests, which were preferentially selected by the trace makers for construction of a well‐constructed and resistant wall. Morphotype B contains more robust tests of Nummulites, while morphotype C is dominated by saddle‐shaped tests of Discocyclina. Nummipera eocenica was produced during a period of seafloor stabilization caused by a deepening. The succession of the morphotypes B, A reflects diminishing energy and increasing water depth. Probably morphotype C represents even lower energy environment than morphotype A. The trace fossil is interpreted as a domichnion, which wall was constructed for protection. The trace maker can be considered between polychaetes and crustaceans; however, comparisons to the closest recent analogues, the polychaete Diopatra cuprea or alpheid shrimps, are not satisfactory. □Bartonian, burrow, Carpathians, large foraminifera, trace fossils. 相似文献