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1.
The effect of various growth regulators on the atrophy of terminal flower buds was tested on Baccara roses. Treatments with gibberellic acid (GA) and 2-chloroethyl trimethyl ammonium chloride (CCC) reduced the atrophy of the flowers. The application of 2-chloroethyl phosphonic acid (CEPA) to the buds enhanced abortion, and the effect was more marked on the lower than on the upper shoot. The stage most sensitive to CEPA was when the shoots were 8–35 cm long. Treatment with abscisic acid (ABA) had no effect of the degree of “blindness”, nor did kinetin applied to the apex affect flowering. Spraying with benzyl adenine increased both the rate of sprouting of the lateral buds and the extent of “blindness” of the sprouting shoots, but did not reduce the number of flowers per branch.  相似文献   

2.
The induction of -amylase by exogenously supplied gibberellin A1 (GA1) and GA4 in embryoless caryopses of Hordeum vulgare (cv. Himalaya) was determined indirectly by measuring reducing sugars released from the endosperm. The presence of the inhibitors of GA biosynthesis, 2-isopropyl-4-dimethylamino-5-methylphenyl-1-piperidinecarboxylate methyl chloride (Amo 1618), Ancymidol, 2-chloroethyl trimethyl ammonium chloride (CCC) or (R,S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,3-triazolyl)pentan-3-ol (PP333) did not inhibit -amylase production by either GA1 or GA4.Abbreviations Amo-1618 2-isopropyl-4-dimethylamino-5-methylphenyl-1-piperidinecarboxylate methyl chloride - CCC 2-chloroethyl trimethyl ammonium chloride - cv. cultivar - GA gibberellin - GC gas chromatography - GC-MS combined gas chromatography-mass spectrometry - PP333 (R,S)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,3-triazolyl) pentan-3-01  相似文献   

3.
Plasmid pJP4 is an 80-kilobase, IncP1, broad-host-range conjugative plasmid of Alcaligenes eutrophus encoding resistance to mercuric chloride and phenyl mercury acetate and degradation of 2,4-dichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid, and 3-chlorobenzoate. By the use of cloning, transposon mutagenesis, and restriction endonuclease analysis, a biophysical and genetic map of pJP4 was generated.  相似文献   

4.
The rate of recovery of Pratylenchus brachyurus from cotton roots was enhanced when the tissue was incubated in solutions containing 10 ppm ethoxyethyl mercuric chloride, 50 ppm dihydrostreptomycin sulfate, 50, 100, or 1,000 ppm diisobutylphenoxethyl dimethyl benzyl ammonium chloride, or mixtures of these compounds. Incubation in 10 or 100 ppm zinc sulfate, zinc chloride, or magnesium chloride also enhanced the rate of recovery. Incubation solutions containing 1 or 1,000 ppm zinc chloride or magnesium chloride had no influence on this phenomenon, whereas, 10,000 ppm zinc sulfate, zinc chloride, or magnesium chloride retarded the rate of recovery. A t all incubation intervals during the first 21 days after the roots were removed from soil, the P. brachyurus population consisted of approximately 25% second-stage juveniles, 44% third and fourth-stage juveniles, and 31% females. At least 88% of the second-stage juveniles and 51% of the third and fourth-stage juveniles passed through a single 325-mesh sieve, whereas, 84% of the females collected were retained on a sieve of this mesh.  相似文献   

5.
In the current study, 48 male rats were classified into four groups (12 rats/group): 1—control group received 1 ml distilled water, 2—origanum oil group treated daily with oral dose of origanum oil (5 mg/kg) for 30 and 60 days, 3—mercuric chloride group treated daily with oral dose of mercuric chloride (4 mg/kg) for 30 and 60 days, and 4—origanum oil + mercuric chloride group treated with both origanum oil and mercuric chloride (5 and 4 mg/kg, respectively) for 30 and 60 days. All treatments were carried out by stomach tube. The results showed that administration of mercuric chloride induced significant increase in thiobarbituric acid reactive substance (TBARS) and decrease in glutathione (GSH), catalase (CAT), and super oxide dismutase (SOD) in testis and spleen tissues. The data also showed significant increase in tumor necrossis factor-α (TNF-α), 8-hydroxy deoxyguanosine (8-OHDG), acid phosphatase (ACP), urea, and creatinine. Furthermore, significant decreases in serum zinc (Zn), copper (Cu), magnesium (Mg), iron (Fe), and testosterone in mercuric chloride group were recorded. The histological examination of testis and spleen tissues showed some degenerative changes while significant improvement in the antioxidant levels, biochemical, trace elements, and histological changes were observed in mercuric chloride group treated with origanum oil. It could be concluded that origanum oil through its antioxidant potential may possess health promoting properties and could protect cells from oxidative damage induced by mercuric chloride.  相似文献   

6.
The influence of various factors on the performance of organomercury seed treatments in controlling seed-borne Septoria nodorum was studied in laboratory experiments. Control was least effective on the most heavily infected seed samples. On heavily infected seed ethyl mercuric chloride was more effective than phenyl mercuric acetate, although 5 wk storage of the treated seed before sowing increased the effectiveness of the latter compound. Effectiveness was not generally influenced by differences in soil moisture. Seedling vigour was significantly improved by levels of mercury below those applied commercially. The significance of seed treatment in the epidemiology of Septoria disease is discussed.  相似文献   

7.
A synergistic factor than enhances the infection of a nuclear polyhedrosis virus in the armyworm, Pseudaletia unipuncta, was isolated from the occlusion body (capsule) of a granulosis virus of the armyworm. Disc electrophoresis indicated that the purified factor was a single homogeneous compound. Chemical identification and amino acid analysis showed that it was a simple protein, with a molecular weight of 152,000–163,000. Proteolytic enzymes did not markedly reduce the activity of the factor. It could be stored at ?20°C or lyophilized. The synergistic factor displayed properties of an enzyme. It enhanced the hydrolysis of p-nitrophenyl esters of fatty acids with an optimum of pH 9.0. The relative hydrolytic activity increased with increase in number of carbon atoms in the fatty-acid chain from 2 to 8 and gradually decreased with the number of carbon atoms from 10 to 18. Copper sulfate markedly and mercuric chloride completely prevented enhancement of the hydrolysis of butyrate. When the synergistic factor was fed to larvae with mercuric chloride, it did not enhance the nuclear polyhedrosis virus.  相似文献   

8.
OBJECTIVES: In this study, we have sought to establish the cellular origin and proliferative status of the renal parenchyma as it regenerates after damage induced by mercuric chloride, with or without erythropoietin treatments, that might alter the response. MATERIALS AND METHODS: Female mice were irradiated and male whole bone marrow was transplanted into them. Six weeks later recipient mice were assigned to one of four groups: control, mercuric chloride treated, erythropoietin treated and treated with mercuric chloride plus erythropoietin. RESULTS: Tubular injury scores were high 3 days after mercuric chloride and had recovered partially after 14 days, in line with serum urea nitrogen levels. Confocal microscopy confirmed the tubular location of bone marrow-derived cells. A 'four-in-one' analytical technique (identifying cell origin, tubular phenotype, tubular basement membranes and S-phase status) revealed that tubular necrosis increased bone marrow derivation of renal tubular epithelium from a baseline of approximately 1.3% to approximately 4.0%. Erythropoietin increased the haematocrit, but no other effects were detected. CONCLUSION: As 1 in 12 proximal tubular cells in S-phase was derived from bone marrow, we conclude that in the kidney, the presence of bone marrow-derived cells makes a minor but important regenerative contribution after tubular necrosis.  相似文献   

9.
The effect of growth retarding compounds, (2-chloroethyl)trimethylammonium chloride (CCC), 2-isopropyl-4-dimethylamino-5-methylphenyl-1-piperidinecarboxylate methyl chloride (AMU-1618), tributyl-2,4-dichlorobenzylphosphonium chloride (Phosfon D) and N-dimethylamino succinamic acid (B-995) on α-amylase production in germinating barley seed was studied. Seeds were germinated in growth retardants in presence and absence of gibberellic acid (GA3). CCC, AMO-1618 and Phosfon D inhibitedα-amylase production in germinating seed and the effect was reversed by GA3 Phosfon D and AMO-1618 were stronger inhibitors of α-amylase production than CCC. CCC was by far the strongest inhibitor of all the other analogs tested. B-995 was comparatively only slightly inhibitory. The results reported here, when viewed in light of the results of other workers, provide good evidence that CCC, AMO-1618 and Phosfon D inhibit α-amylase production by inhibiting the synthesis of gibberellin or gibberellin-like hormone(s) during germination of barley seed. Consistent with other reports, B-995 possibly acts by other mechanism (s).  相似文献   

10.
This study was undertaken in order to assess the effects of metabolism and complexations with amino acids on the renal uptake of mercury using rat renal cortex slices as the experimental system. Mercury levels attained in the slices after 60 min of incubation were 50% higher with mercuric cysteine than with mercuric chloride. This enhancement of uptake with mercuric cysteine was reduced in the presence of a tenfold molar excess of histidine or lysine, but not by serine. Excess cysteine markedly increased mercury uptake. Incubation at 25 degrees significantly reduced uptake of mercuric cysteine, but not mercuric chloride. Anaerobic conditions and incubation in the presence of DNP each reduced mercuric cysteine uptake to the control level of mercuric chloride without affecting uptake of mercuric chloride. The differential aspects of metabolism on the uptake of mercuric cysteine and mercuric chloride and the competitive effects obtained with amino acids known to compete with cysteine in renal reabsorption support the hypothesis that a portion of the renal uptake of mercury operates through amino acid transport mechanisms acting on mercury-amino acid complexes.  相似文献   

11.
A single-step spraying of wheat during shooting under field conditions with solutions of CCC (chlorocholine chloride), CCC and urea, CCC and Aminex (ammonium salt of 4-chloro-2-methylphenoxyacetic acid), or CCC, urea and Aminex caused changes both in numbers and composition of the rhizosphere mycoflora. The numbers both in the rhizosphere of differently treated plants and in the free soil decreased during vegetation. A more pronounced effect in the number of fungi was demonstrated in plants treated only with CCC. The difference was more considerable during first 10 days after the spray. As far as the relative occurrence of individual genera in the rhizosphere soil is concerned, fungi of the generaPenicillium Link ex Fr.,Fusarium Link ex Fr.,Verticillium Nees andTrichoderma Pers were most influenced after the treatment with the used agents.  相似文献   

12.
Enzymic formation of 14C-kaurene from 2-14C-mevalonate was carried out with a cell-free system of Cucurbita pepo L. It was shown that either heating of the enzyme system or the addition of the growth retardants (2-chloroethyl)-trimethylammonium chloride and 2′-isopropyl-4′ (trimethylammonium chloride)-5′-methylphenyl piperidine-1-carboxylate prevented the synthesis of 14C-kaurene. Experiments in which 14C-kaurene was applied to seedlings of Pharbitis nil revealed that the kaurene is converted to at least two compounds present in the acidic ethyl acetate fraction, containing free gibberellins, as well as in the second acidic ethyl acetate fraction, containing the released bound gibberellins. One of the compounds cochromatographed with gibberellic acid; the other compound is possibly a break-down product of gibberellic acid with no biological activity.  相似文献   

13.
The effectiveness of organomercury seed treatments in controlling seedling disease caused by seed-borne Fusarium nivale was studied in pot experiments. Ethyl mercuric chloride was more effective than phenyl mercuric acetate (PMA) on barley. Storing treated seed for 6 wk before sowing improved the performance of both compounds. PMA was less effective in controlling F. nivale than Septoria nodorum on wheat, although F. nivale was only slightly less sensitive to PMA in agar plate tests. Control of JF. nivale was usually more effective on wheat than on barley for the two seed samples used. PMA rates two to four times those applied commercially did not completely eliminate infection. Rates of PMA less than about 0–125μg Hg/seed did not significantly control F. nivale on wheat or barley.  相似文献   

14.
Root excision decreases nutrient absorption and gas fluxes   总被引:11,自引:4,他引:7       下载免费PDF全文
The roots of barley plants (Hordeum vulgare L. cv Steptoe) were monitored before and after excision for net uptake of carbon dioxide, oxygen, ammonium, potassium, nitrate, and chloride and for their content of sucrose, glucose, fructose, and malic acid. All fluxes began to attenuate within 2 hours after excision. Net potassium uptake returned to control levels 6 hours after excision, but carbon dioxide, oxygen, ammonium, and nitrate fluxes continued to diminish for the remainder of the observation period. The addition of 0.1 molar glucose or 0.1 molar sucrose to excision medium had no significant effect on these changes in ion and gas fluxes. Net chloride uptake was negligible for all treatments. Sugar and malic acid content of the root declined after excision. Sucrose and glucose levels remained depressed for the entire observation period, whereas fructose and malic acid returned to control levels after 9 hours. These results indicate that excision has profound, adverse effects on root respiration and the absorption of mineral nitrogen.  相似文献   

15.
0.1m 2-chloroethyl trimethyl ammonium chloride is known to cause bleaching of leaves in intact plants. In this experiment chlorophyll and carotenoid levels were examined by standard procedures in order to gain some insight into the nature of this response. It was found that chlorophyll was destroyed, with white areas appearing on the leaves, and that a drop in carotenoid level preceded the destruction. Thus, the results indicate that CCC interferes with isoprene metabolism, lowering carotenoids, and allowing chlorophyll to be photooxidized. This effect on carotenoids has not been previously reported.  相似文献   

16.
A novel method is presented for transesterification of fatty acid esters in phospholipids and triglycerides to benzyl esters while simultaneously recovering free fatty acids as methyl esters. Transesterification is catalyzed by 0.2 M (m-trifluoromethyl phenyl)trimethyl ammonium hydroxide in methylene chloride, 10% (v/v) benzyl alcohol, and 1% (w/v) potassium tert-butoxide, and is complete in 30 min at room temperature. Methyl esters of all common fatty acids separate from the benzyl esters formed from phospholipids. This method has broad utility and is applicable to the formation of esters optimized for detection by absorbance or fluorescence (high performance liquid chromatography), electron capture (gas-liquid chromatography), or negative ion chemical ionization (gas-liquid chromatography-mass spectrometry).  相似文献   

17.
Losses from hard rot, measured by an arbitrary disease index, were reduced by treating the dehusked corms before planting with mercuric chloride (with or without the addition of 10% hydrochloric acid), mercurous chloride (calomel), three proprietary mercury compounds (Aretan, Uspulun and Ceresan) and one proprietary non-mercury compound (Folosan). Calomel was the least effective. All the treatments were relatively less effective when corms with definite lesions were treated.
The weight of clean corms produced per old corm planted (weight index) was usually increased by all the fungicides tried, but calomel and Ceresan were less satisfactory than the others.
Mercuric chloride (3 hr. steep in a 0.1% solution) was not rendered more effective by the addition of hydrochloric acid nor by a preliminary dip in methylated spirits to facilitate wetting, while the addition of a proprietary wetting compound (Agral) was definitely harmful to the corms and usually less effective than mercuric chloride alone. Increase in time of steeping or concentration of mercuric chloride was not beneficial and was sometimes harmful. Reduction in time of steeping to 1 hr. gave promising results.
Treatment in November had some advantages over treatment in March.
All the mercury compounds tended to delay flowering, this being most marked in the presence of the wetting compound. Stunted foliage and poor quality flowers resulted from the use of Ceresan.  相似文献   

18.
An enzyme (S-1) which catalyzes the splitting of carbon-mercury linkages of organomercury compounds was purified about 24-fold from the cell-free extract of mercury-resistant Pseudomonas K-62 strain by treatment with streptomycin, precipitation with ammonium sulfate, and successive chromatography on Sephadex G-150, DEAE-Sephadex, and DEAE-cellulose. A purified preparation of the enzyme showed a single band on polyacrylamide gel electrophoresis, and was colorless. The molecular weight of the enzyme was estimated to be 19,000, and Km was 5.3 X 10(-5) M for p-chloromercuribenzoic acid (PCMB). The temperature and pH optimum for the reaction were 50degrees and 7.0, respectively. The enzyme was capable of catalyzing the decomposition of methylmercuric chloride (MMC), ethylmercuric chloride (EMC), phenylmercuric acetate (PMA), and PCMB in the presence of a sulfhydryl compound to form a mercuric ion plus methane, ethane, benzene, or benzoic acid, respectively. The mercuric ion thus formed was reduced to metallic mercury by metallic mercury-releasing enzyme (MMR-enzyme).  相似文献   

19.
The main eliminative route for [14C]vinyl chloride after oral, i.v. or i.p. administration to rats is pulmonary; both unchanged vinyl chloride and vinyl chloride-related CO2 are excreted by that route and the other [14C] metabolites via the kidneys. After intragastric administration, pulmonary output of unchanged vinyl chloride is proportional to the logarithm of reciprocal dose. Excretion patterns after i.v. and i.p. injections are predictable from the characteristics of excretion following oral administration. Pulmonary excretion of unchanged vinyl chloride after oral dosing is complete within 3-4 h, but pulmonary elimination of CO2 and renal excretion of metabolites occupies 3 days. In comparison, 99% of a small i.v. dose is excreted unchanged within 1 h of injection; 80% within 2 min. The rate of elimination of a single oral doses of [14C]vinyl chloride is uninfluenced by up to 60 days' chronic dosing with the unlabelled substance. The distribution volume of vinyl chloride as displayed by whole-animal autoradiography agrees with deductions from excretion data. Small localization of 14C in the para-auricular region of appropriate sections occurs in sectioned tubules, belonging possibly to the Zymbal glands. Biotransformation of vinyl chloride into S-(2-chloroethyl) cysteine and N-acetyl-S-(2-chloroethyl) cysteine occurs through addition of cysteine, and biotransformation into: (i) chloroacetic acid, thiodiglycollic acid and glutamic acid, and (ii) into formaldehyde (methionine, serine), CO2 and urea is explicable in terms of an associative reaction with molecular O2 involving a singlet oxygen bonded transition state in dynamic equilibrium with a cyclic peroxide ground state. There is no evidence for chloroethylene oxide formation.Thiodiglycollic acid is the major metabolite of chloroacetic acid in rats; more than 60% of the dose. The interaction of vinyl chloride and of its primary metabolites with the intermediates of mammalian metabolism is discussed in relation to the oncogenicity of that substance.  相似文献   

20.
Glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) was extracted from Pteronarcys californica (Plecoptera) by ammonium sulphate fractionation. The enzyme was treated with three forms of mercury (mercuric chloride, methylmercuric chloride, and phenylmercuric chloride) and their in vitro and in vivo effects on GAPDH were studied. It was found that the orders of toxicity were reversed in the in vivo-in vitro experiments. Electrophoresis was conducted on both treated and untreated enzyme, and showed no differences in mobilities between the two. The enzyme was not found to be inhibited by 0·1 mM iodoacetic acid and required cysteine for activity.  相似文献   

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