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1.
The extract of green peel of Juglans mandshurica Maxim was extracted by common method for studying its insecticidal activities and analyzing the active components. Results showed that the alcohol extract and the chloroform part of extract （separated with chloroform from alcohol extract） form green peel of J. mandshurica have insecticidal activities in contact toxicity and stomach toxicity against larvae of Lymantria dispar L.. After application of the extracts for five days, the corrected mortality of larvae of Lymantria dispar for both extracts was more than 50% in contact toxicity and stomach toxicity at the concentration of ≥ 5 g·L^-1. The insecticidal activity for both alcohol extract and chloroform part of extract is more effect in contact toxicity than in stomach toxicity, but no significant difference in the insecticidal activities was found between alcohol extract and chloroform part of extract. The active components in the chloroform part of extract from green peel of.J. mandshurica were analyzed by GC-MS. The analyzed results showed that the active components in the chloroform part of extract are： （1） joglone （5-hydroxy-1,4- naphthaoquinone）, the relative content 27.11%, （2） 1,5-Naphthalenediol, the relative content 9.52%, （3） 7-Methoxy-1-tetralone, the relative content 6.81%, （4） Benzofuran, 2,3-dihydro-, the relative content 6.76%, （5） 4-Hydroxy-2-methoxycinnamaldehyde, the relative content 3.99%, （6） 2-Methoxy-4-vinylphenol, the relative content 3.05%.  相似文献   

2.
核桃楸叶乙醇提取物对舞毒蛾幼虫的毒杀效果   总被引：4，自引：0，他引：4  
采用常规提取法浸提核桃楸叶的杀虫活性成分,其中乙醇提取物对舞毒蛾有显著的触杀和胃毒作用,且两种作用方式无显著差异,施药时间≥3 d、药液浓度≥5g/L时,平均校正死亡率均超过50%.核桃楸叶乙醇提取物的触杀和胃毒作用强于氯仿萃取相和乙酸乙酯萃取相.  相似文献   

3.
Synthesis of insecticidal sucrose esters   总被引：1，自引：0，他引：1  
1 Introduction Sucrose fatty acid esters are nontoxic compounds that may be produced from renewable, economical and readily available resources. Free alcoholic hydroxyl groups of sucrose react with aliphatic or aromatic ac- ids to produce sucrose esters. Sucrose esters (SE) have been commercially produced for the food industry, which are widely used in foods, cosmetics, agriculture and pharmaceuticals. Apart from their emulsifing properties, they are completely biodegradable, harm- less to th…  相似文献   

4.
Control of Lymantria dispar L. by biological agents   总被引：1，自引：0，他引：1  
The experiment on control ofLymantria dispar L by using different kinds of biological measures, including nuclear polyhedrosis virus (NPV) ofLymantria dispar L., BtMP-342, sex-attractant as well as botanical insecticide, was carried out in the forest regions of Inner Mongolia in 2003. Two concentrations (2.632×106 PIB·ml−1 and 2.632×107 PIB·ml−1) ofLymantria dispar L. NPV were sprayed on the 2rd-instar-larvae ofL. dispar and 70% and 77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instar larvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific Forestry Research Center also showed a good result in trappingL. dispar adults. The self-produced botanical insecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains, China, exhibited a good control result in controlling the larvae ofL. dispar, and 82% mortality was observed when spraying primary liquid of the botanical insecticide on the 3rd–5th-instar-larvae in lab. Foundation item: This paper was supported by Natural Science Foundation of Heilongjiang Province (C0235) and Youth Foundation of Harbin City (0061218024). Biography: ZHANG Guo-cai (1964), male, Ph. Doctor Candidate, associate professor in School of Forestry, Northeast Forestry University, Harbin 150040, P. R. China. Responsible editor: Song Funan  相似文献   

5.
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   

6.
Lymantria dispar (Lep., Lymantriidae), an important forest defoliator, is host for a variety of entomopathogenic microsporidia. These are obligate intracellular parasites that completely depend on resources provided by the hosts. The microsporidia infecting L. dispar differ in the host tissues that become infected as well as in virulence, with presumably different effects on host physiology. Endoreticulatus schubergi infects the midgut tissue of the host; its virulence is low. We studied the effects of infection with E. schubergi on carbohydrate and lipid levels in the L. dispar host larva. Trehalose titer in the hemolymph increased with larval age. There were no significant differences between infected and uninfected hosts. Glycogen content of the host tissue also increased with age. Levels of this storage carbohydrate were significantly lower in infected larvae at a late stage of infection when insects were either full grown larvae prior to pupation (57.4 ± 5.7 and 36.4 ± 5.2 μg/mg in uninfected controls and infected hosts, respectively) or prepupae (53.2 ± 3.4 vs. 34.7 ± 4.7 μg/mg). Lipid levels in host tissue likewise increased over time and were slightly but not significantly lower in infected L. dispar at a late stage. The results suggest that L. dispar larvae are able to compensate for most of the loss of nutrients to the developing microsporidia. Differences between these findings and the effects of infection with the virulent microsporidium, Vairimorpha disparis, that infects the host’s fat body and causes severe depletion of nutrients in L. dispar larvae are discussed.  相似文献   

7.
The life circle and bionomics ofLymantria dispar was studied from the May to the July of 1997 in Tulihe Forestry Enterprise of Inner Mongolia. The results showed thatL. dispar has one generation in a year, larvae overwinters in eggs, and last 50 days to grow up. From the completing of larvae period to the appearing of adults lasts 11 days. The study made a basis for the period forecasting of L.dispar in Inner Mongolia.  相似文献   

8.
High antifeedancy and low toxicity of the plant preparation Neem (azadirachtin), on the gypsy moth, Lymantria dispar L. larvae were proved under laboratory conditions. A high index of Neem antifeedancy was confirmed in all tested concentrations. Under laboratory conditions the Neem had satisfying antifeedancy on Leptinotarsa decemlineata Say third instar larvae too. Field experiments also proved that the foliage protective effect of Neem was very significant. Experiments showed that some antifeedants or repellents, such as Neem, should control olygophagous (L. decemlineata, Coleoptera) insects as well as very polyphagous insects such as L. dispar (Lepidoptera). As a biological, plant-derived preparation, Neem could be suitable for integrated pest management (IPM) programs, especially in small orchards, parks, and tree rows in urban environments and on small private gardens.  相似文献   

9.
Summary The direct and indirect damaging effect of fertilizers, in forest perts.Insects depend on the physiological conditions of the plants on which they feed. Heat and dryness increases the content of sugar, aproximatly up to 50%, and other untrients in the plants during rainy seasons the proportion of sugar decrease. The osmotic valuation can be used as indicator of the physiological conditions of the plants.The high concentration of sugar stimulates the development of the insects. But they also thrives on plants with high turger. For example young larvae crowth only on newly burst open most turgescent needles and leaves. This will be demonstrated by the larvae ofLiparis monacha L.,Limantria dispar L., Pristiphora abietina Christ. and two Dreyfusia on the young needles of the silvec fir.Radio-active fertilizers enter the plants and insect feeding. Phosphorus (P 34) is mainly found in the intesties Calcium (Ca 45) is much more deposited in the Vasa Malpighi. Wie have the idea that the fertilizing may over-feed this organs.Our experiences demonstrates that the physiological conditions of the plants in spring and summer has upon the insects no decisive effect. The direct damaging effect of the fertilizers on the larvae is more violent. The absorbed fertilizers dangerously disturb the metabolism of the insects.  相似文献   

10.
试验研究了饲毒龄期、饲毒浓度对舞毒蛾存活、幼虫体质量、虫尸质量和含毒量的影响以及饲毒时间对舞毒蛾含毒量的影响.结果表明:饲毒龄期和饲毒浓度对幼虫存活率和体质量增长均有不同程度的影响,饲毒龄期越小、饲毒浓度越高,死亡时间越早,死亡率越高,体质量增长越缓慢;而且饲毒时龄期越小、饲毒浓度越高,虫尸质量也越小,其含毒量也越低.饲毒时间与含毒量成抛物线型,饲毒时间过短或过长,体内含毒量均较低.由于5龄幼虫饲毒后有78％以上个体发育至蛹期,不发生死亡现象,因此,室内增殖舞毒蛾核型多角体病毒时,应选取4龄初幼虫喂饲1.0×106 PIB·mL-1病毒为宜,接毒10d后开始收集饲毒幼虫.  相似文献   

11.
Ranchers need alternative livestock feeds when herbaceous forages become limiting in summer. Our objectives were to determine: (1) leaf and stem biomass components, (2) nutritive value [in vitro dry matter digestibility (IVDMD), total nonstructural carbohydrate (TNC), N, and N digestibility] of leaves for animal browse, (3) concentration of the secondary metabolites robinin and mimosine, and (4) in vitro leaf and bark toxicity for black locust (Robinia pseudoacacia L.) and mimosa (Albizia julibrissin Durz.), respectively, pollarded at 50 cm in Arkansas, USA. Black locust exceeded mimosa for every yield component (leaf mass tree−1, leaves shoot−1, shoots tree−1, shoot mass tree−1, stem basal area, and biomass tree−1) except mass leaf−1. Projected yields were 1,900 and 1,600 kg leaves ha−1 for black locust and mimosa, respectively, assuming a population of 12,300 trees ha−1. Mimosa leaves had greater IVDMD, TNC, and N digestibility than black locust. Mimosa leaves exceeded the nutritional N requirements of growing cattle (Bos taurus L.) and goats (Capra hircus L.), but protein supplementation would be needed for growing goats grazing black locust leaves. Tissue concentrations of secondary metabolites robinin and mimosine were below detectable limits in black locust and mimosa, respectively. The extract of black locust bark, but not leaves, was toxic to bioassayed African green monkey (Cercopithecus aethiops L.) cells. Either black locust or mimosa could provide moderate quantities of high quality, rotationally grazed forage for goats during summer months when herbaceous forage may in short supply.  相似文献   

12.
The effects of the arbuscular mycorrhizal (AM) fungus Glomus mosseae on plant growth, leaf solutes and root absorption area of trifoliate orange (Poncirus trifoliata (L.) Raf.) seedlings were studied in potted culture under water stress conditions. Inoculation with G. mosseae increased plant height, stem diameter, leaf area, shoot dry weight, root dry weight and plant dry weight, when the soil water content was 20%, 16% and 12%. AM inoculation also promoted the active and total absorption area of root system and absorption of phosphorus from the rhizosphere, enhanced the content of soluble sugar in leaves and roots, and reduced proline content in leaves. AM seedings had higher plant water use efficiency and higher drought tolerance than non-AM seedlings. Effects of G. mosseae inoculation on trifoliate orange seedlings under 20% and 16% soil water content were more significant than under 12% soil water content. AM infection was severely restrained by 12% soil water content. Thus, effects of AM fungi on plants were probably positively related to the extent of root colonization by AM fungi. The mechanism of AM fungi in enhancing drought resistance of host plants ascribed to greater osmotic adjustment and greater absorption area of root system by AM colonization. __________ Translated from Journal of Plant Physiology and Molecular Biology, 2005, 30(5): 583–588 [译自: 植物生理与分子生物学报, 2005, 30(5): 583–588]  相似文献   

13.
Alkaloids from Sophora alopecuroids were bioassayed with Clostera anastomosis for their antifeedant and growth inhibitory effects. The antifeedant rate in choice test reached 62%–86% at the dose 2.5 mg/mL, while in non-choice bioassay the rate was only 20%–29%. In choice bioassay, the antifeedant rate increased with larval instars of C. anastomosis and did not in non-choice experiment. The alkaloids also imposed a strong influence on the growth of C. anastomosis larvae, i.e., after feeding on the leaves treated with alkaloid, the larvae lost their weight, weight gain, and relative growth rate (RGR) significantly when compared with the controls. In the second day after treatment with the dose at 10 mg/mL of the alkaloid, the RGR reduced by 39.8%, and the food intake and the feces weight were respectively 57.7% and 57.4% of the controls. The approximate digestibility (AD) increased significantly, and the efficiency in converting digested food (ECD), and the efficiency in converting ingested food (ECI) decreased greatly after feeding the treated leaves. Moreover, the eggs laid per female were also inhibited by this alkaloid. The significance and prospect of the alkaloids in controlling forest insect pests were also discussed. __________ Translated from Scientia Silvae Sinicae, 2005, 41(4) [译自: 林业科学, 2005, 41(4)]  相似文献   

14.
Chloroform-methanol extract of mature leaves from Solanum villosum Mill (Solanaceae: Solanales) was investigated to establish its biocontrol potentiality under laboratory condition against larval forms of Anopheles subpictus Grassi (Diptera: Culicidae), the vector of human malaria. All the graded concentrations (30, 50, 100 and 200 ppm) showed significant (P < 0.05) larval mortality and results of regression equations revealed that the mortality rates were positively correlated with the concentrations of the extract (R 2 close to 1). LC50 values for all instars were between 24.20 and 33.73 ppm after 24 h and between 23.47 and 30.63 ppm after 48 h of exposure period. Significant changes in the larval mortality (F < 0.05) was also recorded between instars during single “ANOVA” analysis. This extract also demonstrated no toxicity to larvae of Chironomus circumdatus Kieffer (Diptera: Chironomidae) which were found to be present as most common non-target dipteran insect in the habitats of A. subpictus. Qualitative and chromatographic analysis of the solvent extract revealed the presence of carbohydrates, saponins, terpenoids, volatile oil, steroids, phenols and flavonoids as major bioactive phytochemicals.  相似文献   

15.
Effects of neem-extracts on cater pillars of the gypsy moth, Lymantria dispar L. The effects of neem extracts(Azadirachta indica) (0.02%; 0.2% 0.5%) were tested on caterpillars of the gypsy moth (Lymantria dispar). The laboratory experiments showed, that these concentrations suppress the development and prohibit the moultin of caterpillars. The mortality reached 100% in all experiments. Addition test carried out under field conditions indicated that the activity of neem extract sprayed on oakleafs(Quercus robur) remained unchange after 12 days of application.  相似文献   

16.
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   

17.
Three treatments including mechanical damage, Lymantria dispar attacking and daubing oral secretions of the insects on mechanically damaged cut were conducted on Populus simoniixPopulus pyramibalis c.v. in order to find the genuine reason leading to effective resistance response of tree to insects attacking. The release situation of the induced volatiles of the plant was analyzed by TCT-GC/MS at 24 hours after damages. The results indicated that some of the volatiles such as (Z)-3-hexenyl acetate, decanal, 3-hexenyl isovalerate, nonanal, ocimene, and 2-cyanobutane can be induced by both insects attacking and mechanical damage, while 2,6-dimethyl-1,3,5,7-octatetraene, 2-methyl-6-methylene-1,7-octadien-3-one, caryophyllene,Isovaleronitrile, diethyl-methyl-benzamide, and dicapryl phthalate were only induced by insects attacking. Such difference in volatiles was attributed to that there existed active components in oral sections of the larvae of Lymantria dispar  相似文献   

18.
Rapid changes of induced volatile organic compounds in Pinus massoniana   总被引：1，自引：0，他引：1  
Using the thermal-desorption cold trap gas chromatography/mass spectrometer (TCT-GC-MS) technique, the composition and relative contents of volatile compounds were analyzed in undamaged (control), insect-damaged (ID) and artificially-damaged (AD) leaves of Pinus massoniana in field at different times and levels of damage. Results showed that although volatile substances were highly released earlier in AD leaves plants, they were significantly less abundant in AD than in ID leaves treatments. Also, the damage level considerably influenced the changes of induced volatile products from leaves. Compared with the control, the emission rate of camphene, β-pinene, phellandrene, caryophyllene and (E)-farnesene was high after 1 h in 25%–40% ID-affected leaves, whereas that of tricyclene, myrcene, camphene, β-Pinene, phellandrene and caryophyllene reached its maximum after 24 h in 60%–75% ID-affected leaves. In the same manner, some volatile compounds in the AD leaves treatment displayed their peaks just after 1 h, but others after 24 h. The AD and ID leaves at the damage level of 25%–40% did not exhibit an obvious regularity with time; however, in 60%–75% AD leaves, peaks of volatile substances were attained after 1 or 2 h. Our results also showed that the relative content of β-pinene increased and was higher in damaged than control plants. β-pinene plays an important role in inducing the insect resistance of P. massoniana trees. __________ Translated from Scientia Silvae Sinicae, 2006, 42(4): 65–70 [译自: 林业科学]  相似文献   

19.
The biological activity of essential oil extracted from coriander, Coriandrum sativum L. (Apiaceae) against eggs, larvae and adults of Tribolium castaneum (Herbst) was investigated in a series of laboratory experiments. Bioassays conducted in air-tight glass chambers showed vapour toxicity and strong repellency on filter paper arena test towards all the stages used. Responses varied significantly (P < 0.001) within insect stages, dosages and exposures. At 12.0 μg/ml dosage, mortality of adults reached 95%, but for 12-, 14- and 16-days larvae, mortalities were 65, 74 and 82%, respectively. On the developmental inhibition, individuals fumigated at the larval stage confirmed that the percentage of larvae reaching to pupal stage and pupae to adult stage, decreased significantly (P < 0.001) with increasing dosage concentration. The oil fumigation yielded 100% mortality for T. castaneum larvae, pupae and adults at 0.08 μg/ml dosage. The oil had fumigant activity against eggs and the toxicity progressively increased with increased exposure times and concentrations. One hundred per cent T. castaneum egg mortalities were obtained with oil fumigation at 20 μg/ml and 96 h exposure period. C. sativum oil also showed highly repellent activity to the adults of T. castaneum, with overall repellency was 90% and at a dosage of 12 μg/ml repellency was 100% in a filter-paper arena test.  相似文献   

20.
Extracts of 121 medicinal and ornamental plants were screened for insecticidal and growth regulating activity to milkweed bug, Oncopeltus fasciatus Dallas. The most effective extracts stemmed from Inula helenium L., Rumex crispus L., R. acetosa L., Asarum europaeum L., and Calendula officinalis L. All these extracts exerted growth inhibiting activities and moderate or low acute toxicity. Most promising were extracts of dried roots of I. helenium. Besides a moderate chronic toxicity which reduced the fitness of the milkweed bug, the treatment produced overaged nymphs, supernumerary nymphs, disturbances of the moulting process, morphological defects, delay of adult maturation and reduction of fecundity. In addition, I. helenium extracts had a strong antifeedant effect when topically applied and very strong repellent effect when applied to the food (peeled sunflower kernels). It is obvious that the extract contains several active constituents. Such a cocktail may reduce the threat of rapid resistance development.  相似文献   

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