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1.
《Journal of Sustainable Forestry》2013,32(3-4):57-61
Abstract The effects of different concentrations of cold and hot aqueous extracts of G. sepium on C. maculatus, the storage pest of cow-pea were examined. The extracts had a killing effect on the weevils. The percentage mortality of the weevils increased with the increase in the extract concentrations. Statistical analyses at 5% level revealed that significant differences abound in the efficacies of the cold and hot aqueous extracts. The hot aqueous leaf and bark extracts tend to have more toxic effect than the cold aqueous extracts. Also, extracts from the bark tend to be more toxic to the weevils than those of the leaves. 相似文献
2.
Metarhizium anisopliae sensu stricto (ss) (Metsch.) Sorok. isolate ICIPE 07 is being developed as biopesticide for the control of ticks. In addition,
leaf extracts of Calpurnia aurea Benth, and the attraction aggregation and attachment pheromone (AAAP) are being used as ticks’ attractant. The three agents
are being considered for use in combination in an autodissemination approach, whereby ticks that are attracted to semiochemicals
are infected with the inoculum. Experiments were therefore conducted to evaluate in vitro the compatibility between C. aurea, AAAP, and the M. anisopliae on vegetative growth, conidial production, and spore viability. Calpurnia aurea leaf extract was compatible with the fungus at all the concentrations tested, whereas AAAP inhibited all the fungal growth
parameters. The virulence of M. anisopliae formulated in emulsifiable extracts of C. aurea was also tested against different developmental stages of Rhipicephalus appendiculatus in laboratory bioassays. No significant differences in virulence were observed between M. anisopliae applied alone and M. anisopliae formulated in different concentrations of C. aurea leaf extracts. These results suggest that C. aurea leaf extracts is compatible with M. anisopliae and could be mixed together for “spot-spray” treatments as low-cost and environmental-friendly technology to control ticks
in grazing field, while AAAP should be used separately. 相似文献
3.
Gry Alfredsen Halvor Solheim Rune Slimestad 《European Journal of Forest Research》2008,127(5):387-393
The inhibitory effect of methanol bark extracts from six deciduous and three coniferous European tree species were bioassayed
against eight fungi from the different damage categories, brown rot, white rot, canker and blue-stain. This is the first report
providing data on the antifungal activity of several Europaen tree species against fungi within these damage categories. Generally
the decay fungi were more inhibited by the bark extracts than the blue-stain fungi, while the lowest inhibition was found
among the cancer fungi. The main pattern found between the fungal groups in relation to the bark extracts in this study is
believed to be caused by the route of ingress. Acer platanoides bark extract proved to be the most efficient bark extract tested, significantly reducing the growth rate of all tested fungi.
Betula pubescens bark extract generally gave the weakest reduction in growth rate. In this study, the conifer bark extracts were in general
more active against the canker and blue stain ascomycete fungi than the deciduous trees extracts. 相似文献
4.
Hymenoscyphus fraxineus, the causal agent of common ash dieback, possesses a low level of genetic diversity in Europe. The introduction of novel strains of this fungus must be prevented, due to the possible emergence of new virulence alleles, which could result in the infestation of the small proportion of hitherto resistant or tolerant ash trees. More comprehensive knowledge of the host spectrum of H. fraxineus is necessary for preventing further introductions. It is possible that H. fraxineus manifests itself in hosts beyond the genus Fraxinus, though this proposition has received little attention thus far. Two in vitro experiments were set up to investigate whether privet (Ligustrum vulgare) could serve as a host: germination rate of fresh H. fraxineus ascospores and colony growth of H. fraxineus were tested on agar media containing leaf extracts of privet, common ash (Fraxinus excelsior) and manna ash (Fraxinus ornus). Two different media with leaf extracts were tested, one with high (60%) and one with low (12%) extract content. Barely any significant differences were recorded in the case of the media with low extract content. Significant effects occurred only at the higher extract content level: germination was completely inhibited on the privet medium. Mycelial growth on the privet medium was slower than on both the common ash and manna ash media and, in addition, one of the three H. fraxineus strains was completely inhibited. These observations indicate the presence of inhibitors in privet. It is therefore unlikely to be a suitable host for H. fraxineus. 相似文献
5.
野扇花果肉和胚乳发芽抑制物的研究 总被引：1，自引：0，他引：1
通过采用野扇花果肉和胚乳的水浸提液对白菜种子进行发芽试验,结果表明:果肉水浸提液高浓度时显著抑制白菜种子的萌发,但低浓度时反而促进种子的萌发;胚乳水浸提液对白菜种子的萌发没有显著影响。2种水浸提液均对幼苗的根和子叶的伸展有一定的抑制作用。 相似文献
6.
Radical scavenging activity and composition of raspberry (Rubus idaeus) leaves from different locations in Lithuania 总被引：1，自引：0，他引：1
Raspberry (Rubus idaeus) leaves, collected in different locations of Lithuania were extracted with ethanol and the extracts were tested for their antioxidant activity (AA) by using ABTS(.)(+) decolourisation and DPPH(.) scavenging methods. All extracts were active, with radical scavenging capacity at the used concentrations from 20.5 to 82.5% in DPPH(.) reaction system and from 8.0 to 42.7% in ABTS(.)(+) reaction. The total amount of phenolic compounds in the leaves varied from 4.8 to 12.0 mg of gallic acid equivalents (GAE) in 1 g of plant extract. Quercetin glucuronide, quercetin-3-O-glucoside and rutin were identified in the extracts. 相似文献
7.
Chloroform, ethyl acetate, butanol and methanol extracts of fruit mesocarp of Balanites aegyptiaca and five fractions from the methanol extract were tested against the Aedes aegypti mosquito larvae. All extracts showed larvicidal effects however the highest larval mortality was found in methanol extract. One fraction obtained from the silica gel column chromatography of the latter was found most effective for larval mortality. This fraction also interfered with adult emergence. A concentration of 0.0014% (w/v) of this active fraction showed inhibition of the 50% of the test larval population from emerging adults (EC(50)). The analysis of total saponin content of these tested extracts and fractions revealed a strong correlation between saponin content and larval mortality. 相似文献
8.
Christian Ulrichs Inga Mewis Sujit Adhikary Atanu Bhattacharyya Arunava Goswami 《Journal of pest science》2008,81(2):79-84
Antifeeding and toxic effects of chemical extracts from Porteresia coarctata Takeoka on the insect pest Spodoptera litura (F.) were investigated in the laboratory. Hexane extracts of P. coarctata leaves were re-dissolved in dimethyl sulfoxide and applied in water to leaves of Ricinus communis L. (castor). A concentration of 1,000 and 2,000 ppm extract exhibited significant antifeeding and toxic effects to third
instar larvae when compared to the same concentration of dimethyl sulfoxide in water as control. One day after feeding on
extract-treated castor leaves, the mortality of S. litura larvae was 50%. Mortality increased to 95% after 11 days at a dosage of 2,000 ppm. Compared to the control, third instar
larvae fed on castor leaves treated with P. coarctata leaf extract at different concentrations showed significant reduction in protein and DNA content in the fat body and midgut
tissues. Results demonstrate the insecticidal and antifeedant properties of P. coarctata leaf extract against the generalist pest S. litura leading to biochemical changes in the insect body. Thus, P. coarctata contains phytochemicals, and the extract, in crude and pure form, has potential as a botanical insecticide in alternative
control strategies against Lepidoptera pests. 相似文献
9.
The ethanol extracts obtained from both leaf and seed in the Thorn apple (Datura stramonium L.) (Solanaceae) were investigated for acaricidal, repellent and oviposition deterrent properties against adult two-spotted
spider mites (Tetranychus urticae Koch) (Acari: Tetranychidae) under laboratory conditions. Leaf and seed extracts, which were applied in 167,250 and 145,750 mg/l
concentrations, respectively (using a Petri leaf disc-spray tower method), caused 98 and 25% mortality among spider mite adults
after 48 h. The simple logistic regression analysis showed that the independent variable, an increase in the dose of leaf
extract was associated with a significant increase in the death rate of T. urticae females, but an increase in the dosage of seed extracts did not have a significant effect. Using probit analysis and estimating
the parameters with a confidence limit of 95%, we determined the LC50 values of leaf extract to be 70,593 mg/l. According to Pearson’s χ2 test, mites showed the strongest run off to bean leaf surfaces sprayed with both leaf and seed extracts (in sub-lethal doses:
<7,500 mg/l and <25,000 mg/l, respectively) and moved towards surfaces that had not been sprayed with extracts. Furthermore,
repeated measures ANOVA indicated a significant difference between the number of eggs laid on unsprayed bean leaves compared
to bean leaves that were sprayed with leaf and seed extracts at sub-lethal doses, 2,500 and 25,000 mg/l concentrations, respectively.
These results suggest that D. stramonium extracts could be used to manage the two-spotted spider mite. 相似文献
10.
Methanolic extracts of Viscum album ssp. album (mistletoe) grown on different host trees were investigated for their potential antioxidant activity. Scavenging activity was tested by 1,1diphenyl2picrylhydrazyl (DPPH) method and the inhibitory effect on lipid peroxidation was examined by ferric thiocyanate and thiobarbituric acid methods. The extract from mistletoe grown on lime tree in summer showed the highest activity. It was found that antioxidant capacity of the plant differed according to the harvesting time as well as the host tree. 相似文献
11.
Termite feeding behavior and the chemoreception of plant extracts were evaluated to investigate the water extracts from akamatsu
(Pinus densiflora), neem (Azadirachta indica), and their equivalent mixture using pseudoergates of Zootermopsis nevadensis. In behavioral assays, termite preference was akamatsu > akamatsu plus neem > neem. Electrophysiological recordings from
the taste hairs on labial palps showed vigorous impulse discharge to akamatsu extract but much lower response to neem extract.
The response to akamatsu plus neem was mostly the same as that to neem alone, suggesting the neem extracts inhibited the responses
to akamatsu extracts. In the present article, we discuss the correlations between the feeding behaviors and the responses
at their taste cells to these different extracts. 相似文献
12.
Somnath Roy Ananda Mukhopadhyay Guruswami Gurusubramanian 《Journal of pest science》2010,83(4):371-377
The toxicity of four concentrations (1, 5, 10 and 20% w/v) of an aqueous extract from the weed, Clerodendrum viscosum Ventenat (Verbenaceae) was investigated under field conditions of the North Bengal University, Darjeeling, West Bengal, India
for managing two major pests of tea, Camellia sinensis (L), namely the tea mosquito bug, Helopeltis theivora Waterhouse, (Heteroptera: Miridae) and the tea red spider mite, Oligonychus coffeae Nietner, (Acarina: Tetranychidae). Four field trials, two for red spider mite and two for tea mosquito bug, were conducted
during April–May 2008 and October–November 2009 following a Randomized Block design. The aqueous extract of C. viscosum effectively and significantly reduced the mite population as well as infestation of tea mosquito bug by 68–95% and 73–86%,
respectively, and their bioefficacy is comparable to synthetic and neem pesticides. No phytotoxic effect (score 0–5% and grade
1) was observed in the tea bushes sprayed with different doses of aqueous extract of C. viscosum in the field. Made tea samples were taint free. Organoleptic test revealed leaf-infusions and liquor strength as good, scoring
6.5–7.0 on a 10 point scale. Availability and distribution of this weed (C. viscosum) in and around tea-growing areas of sub Himalayan region, along with its processing for the feasibility of including C. visosum extracts in the current IPM programme is discussed. 相似文献
13.
Acacia melanoxylon R. Br. (Blackwood) is a native Australian species that has invaded woodlands and degraded natural habitats in the north western
Iberian Peninsula (Galicia), Spain. Several phenolic (p-hydroxybenzoic, vanillic, p-coumaric, syringic, protocatequic, ferulic acids) and flavonoids (catechin, luteolin, rutin, apigenin, and quercetin) were
identified from methanol extracts of flowers and phyllodes of A. melanoxylon by HPLC. Flowers and phyllodes of A. melanoxylon were soaked separately in the water in a ratio of 1:1 (w/v) for 24 h to prepare aqueous extracts (100, 75, 50 and 25%) and
distilled water was used as control. The seeds of three native plants, cocksfoot (Dactylis glomerata), perennial ryegrass (Lolium perenne), common sorrel (Rumex acetosa) and a general test crop lettuce (Lactuca sativa) were grown in perlite culture and aqueous extracts of A. melanoxylon (flowers and phyllodes) were applied exogenously at various concentrations. A. melanoxylon flowers extract (100%) inhibited the shoot length of D. glomerata and L. perenne by 31 and 20% of the control, respectively. Leaf and root fresh weights of L. perenne, D. glomerata, and L. sativa were reduced after treatment with acacia flowers and phyllodes extract. Leaf relative water content of D. glomerata and L. perenne was reduced by acacia flowers and phyllodes extract at all concentrations. Both extracts reduced leaf osmotic potential in
D. glomerata, L. perenne and L. sativa. Quantum efficiency of open PSII reaction centers (Fv/Fm) and quantum yield (ΦPSII) of photosystem II were decreased in L. perenne, D. glomerata; R. acetosa and L. sativa after treatment with acacia flowers/phyllodes extract at 100% concentration. Acacia flowers and phyllodes extract (100%)
inhibited the qP level during all 6 days in D. glomerata, L. perenne, R. acetosa and L. sativa. A significant reduction in NPQ was observed during different days in all four plant species due to Acacia flowers and phyllodes
extract (100%). The δ13C ratios were less negative in L. perenne, D. glomerata and L. sativa as compared to the control. A. melanoxylon flowers and phyllodes extract (100%) significantly reduced leaf protein contents in D. glomerata, L. perenne and in L. sativa. 相似文献
14.
喜树叶提取物的抗菌活性研究 总被引：1，自引：0，他引：1
采用滤纸片法研究喜树叶乙醇提取物和水提物对金黄色葡萄球茼（Staphylococcus aureus）、大肠杆菌（Escherichia coli）、枯草杆茼（Bacillus subtilis）、八叠球菌（Sarcina ventriculi）、黑曲霉（aspergillus niger）、木霉（Trichoderma virid）和青霉（Penicillium chrysogenum）的抗菌活性。结果表明,喜树叶乙醇提取物和水提物对细菌有明显的抑制作用,浓度越大抑制效果越好;喜树叶乙醇提取物对3种霉菌都有抑茼效果,水提物对霉菌没有抑制作用。 相似文献
15.
The extract from leaves of Rhododendron dauricum L. was extracted with 95% alcohol by common method for studying its insecticidal activities. The chemical components of the alcohol extract and relative contents were analyzed by GC-MS. The insecticidal activities of the alcohol extract were tested on the 2nd?3rd instar larvae of Lymantria dispar L. for five days. Five concentrations of the extract samples were designed as 50, 10, 5, 1, and 0.5 g?L?1. The results show that the alcohol extracts from leaves of R. dauricum exhibited insecticidal activities against larvae of L. dispar. The corrected mortality of larvae of L. dispar for was over 50% for both contact toxicity and stomach toxicity at the extract concentration of ≥ 5 g·L?1 after five days of application. The insecticidal activity in contact toxicity is more effect than stomach toxicity for the alcohol extract. Twenty compounds, with total GC relative contents of 93.81% in the alcohol extract from leaves of R. dauricum were identified. The main chemical components in the extract are: (1) 4,5-Dihydro-5-oxo-3-(p-tolyl) isoxazole, with a relative content of 40.03%; (2) 1,3-Benzenediol, 5-methyl-2-(3,7,11-trimethyl-2,6,10- dodecatrienyl)-, (E,E)-, the relative content 18.27%; (3) 3,6-Diphenyl- 1,2,3,4,5,6,7,8-octahydro-1,8-acridinedione, the relative content 3.89%; (4) 6H-[1,2,4]Triazolo[1,5-a]indole, 4a,5,7,8,8a,9-hexahydro-9- methylene-, the relative content 2.99%; (5) 7-Amino-4-methyl-1,8- naphthyridin-2-ol, the relative content 2.64%; (6) 4-Methyl-2,6- dihydroxyquinoline, the relative content 2.63%; (7) 2,4,6- Triaminoquinazoline, the relative content 2.27%; (8) 2(1H)-Quinolinone, 4-hydroxy-1-methyl-, the relative content 2.02%. 相似文献
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17.
Water extracts, methanolic extracts and the petrol ether phase from the fruit and leaves ofMedia azedarach L. were tested against different instar nymphs ofLocusta migratoria migratorioides (R. & F.) under laboratory conditions. Water extracts caused various degrees of mortality and a significant delay in the development and growth of the locusts. Treatments with 3% concn of water extracts from the fruit and leaves at a rate of 40ml/m2 gave 93% and 100% mortalities, respectively, of first instars, and a 3% concn of leaf extract resulted in a mortality of 93.2% of third instars. Antifeedant and/or stomach-poison effect(s) played an important role. MeOH extract had the same efficacy as water extracts, but the petrol ether phase did not show much effect on the locusts. 相似文献
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The antioxidative potential of Achillea alexandri-regis has been studied by measuring the influence of herb extracts on hydroxyl and superoxide radicals' quantity in different in vitro systems. The ethyl acetate extract exhibited hydroxyl radical scavenging activity in all tested biological system (liver homogenate, hemolyzed blood, serum and postmitochondrial liver fraction), whereas butanol extract reduced hydroxyl radicals significantly only in the postmitochondrial liver fraction. Both extracts showed superoxide radical scavenging effect only in hemolyzed blood. 相似文献
20.
柿叶化学成分及其抑菌活性研究 总被引：9，自引：0，他引：9
对柿叶的化学成分进行了定性分析和抗菌活性的研究.通过系统预试,初步确定柿叶中含有生物碱、皂苷、氨基酸、多肽、有机酸、酚类和鞣质、糖类、甾体、总黄酮、强心苷、蒽醌、挥发油等物质.抑制活性试验结果显示:乙醇提取物和乙酸乙酯萃取物对供试的6种细菌有较强的抑制作用;水相对供试的5种真菌有较强的抑制作用,而且对细菌有较小抑制作用;石油醚相对真菌和细菌几乎无抑制作用;正丁醇萃取物对细菌有不同程度的抑制作用,而对真菌无抑制作用.用不同质量浓度的乙酸乙酯提取物进行抑菌活性试验,结果显示:质量浓度越高,其抑菌能力越强,而且,在不同质量浓度下,对测试的6个细菌的抑制活性的大小顺序不一致. 相似文献