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1.
Leafhopper Cicadulina bipunctata is represented the main insect as a pathogen for phytoplasma disease occurring by insect-transmitted plant viruses in date palm orchards. Therefore, it is important to investigate the potential effect of some insecticides against such insect. The adults of leafhopper C. bipunctata were collected from date palm orchards in Alhasa, Eastern province, Saudi Arabia. Three insecticides from different classes--beta-cyfluthrin (pyrethroids), imidacloprid (neonicotinoids) and abamectin (natural compounds)--have been evaluated in vivo against adults C. bipunctata. This stage was exposed to residual film of various concentrations of each insecticide on transparent plastic cups using a Potter precision laboratory spray tower. Bioassay test showed that both beta-cyfluthrin and imidacloprid caused 100% mortality by 500 ppm at 24 h after treatment, whereas abamectin gave the same mortality by 50 ppm at the same time. Toxicity values revealed that abameetin was the most potent insecticide compared with beta-cyfluthrin and imidacloprid, where the lethal concentrations LC50 and LC95 were 24.58 ppm and 116.73 ppm at 3 h after treatment, respectively. Therefore, abamectin can be a possible candidate to be applied on date palm or ground grass by the Ministry of Agriculture after successful field experiments.  相似文献   

2.
Essential oil(EO) of Nigeria-grown Lippia adoensis leaf was analyzed using gas chromatography mass spectrometry(GCMS) and its fumigant and repellent properties against Callosobruchus maculatus were evaluated. Sixteen compounds predominated by monoterpenes were identified. The major compounds were Eucalyptol(28.36%), α-Terpineol(25.99%), γ-Terpinene(15.24%), α-Pinene(5.08%), 1H-Cyclopropa[a]naphthalene(4.25%) and 1, 3, 6, 10-Dodecatetraene(3.74%). Percentage mortality due to fumigant toxicity was dose- and exposure period-dependent. One hour after treatment(HAT), application of L. adoensis leaf EO at 107 μL· L~(-1) air caused significantly(p?0.05) higher mortality(50.00%) than 0.00% mortality observed at 0-53 μL· L~(-1) air, but not significantly(p?0.05) different from 22.50% observed in 80 μL· L~(-1) air. At 3 HAT, application of L. adoensis EO at 80 μL· L~(-1)air caused significantly higher mortality(90.00 %) than mortality observed at 0 μL· L~(-1) air. At 6 HAT, application of L. adoensis EO at 53-107 μL· L~(-1) air caused significantly higher mortality(100.00 %) than that was observed in the control. The same trend was observed at 12 HAT where 100 % mortality observed in 27-107 μL· L~(-1) air was significantly greater than 13.33 % observed in the control. At 3 HAT, percentage repellence was significantly(p0.05) affected by doses. Application of EO at 10-30 μL· cm~(-2) caused class V repellence(86.67%-100%) compared with the control which caused class I repellence(0-20%).  相似文献   

3.
[Objective] The experiment aimed to explore the relations between structure of aconitine, aconitine derivatives and insecticide. [Method] The aconitine derivatives such as 3-acetyl mesaconitine, 3-propionyl mesaconitine, 3-acetyl-13-Benzoyl-mesaconitine and 3-propionyl-13-Benzoyl-mesaconitine were synthesized by mesaconitine with acetic anhydride or propionic anhydride and their insecticidal activities were also determined. [Result] When the concentration was 500 mg/L, the insecticidal activities of mesaconitine against Nilaparvata legen and Aphis were 50% and 30% respectively while the insecticidal activities of 3-acetyl mesaconitine, 3-propionyl mesaconitine, 3-acetyl-13-Benzoyl-mesaconitine and 3-propionyl-13-Benzoyl-mesaconitine against Aphis medicagini were 40%, 30%, 30% and 20% respectively at 500 mg/L. [Conclusion] After hydroxyl esterification, the insecticidal activity of mesaconitine was declined and the existence of hydroxyl at 3rd position in mesaconitine played very important influences on insecticidal activity.  相似文献   

4.
The insecticidal potential of seed powders of Capsicum chinense Jacq.(Solanaceae) and Aframomum melegueta K. Schum.(Zingiberaceae) was tested against Trogoderma granarium(Coleoptera: Dermestidae) in the laboratory at(28±2)℃ and 70%±5% relative humidity. The seed powders were tested at the rates of 0.0%, 0.5%, 1.0% and 1.5%(w/w) of groundnut seeds replicated three times. At the highest rate of treatment, C. chinense caused 56.7% and 76.8% larval mortality at 3 and 7 days post treatment(DPT) respectively while A. melegueta exerted 53.4% and 73.8% larval mortality at 3 and 7 DPT, respectively. Results showed that insecticidal potential of the seed powders against adult mortality of T. granarium and seed damage followed similar trend. The various rates of C. chinense seed powder performed better than A. melegueta seed powder in causing larval and adult mortality and in reducing seed damage. The activity of the seed powders on mortality of the insect, seed weight loss and seed damage were exposure time and rate dependent. A signifi cant reduction(p0.05) in seed weight loss and seed damage was recorded among the treatments and maximum reduction was observed in the seeds treated with the highest rate of C. chinense seed powder. Percentage seed damage signifi cantly(p0.05) decreased with increase in the rate of treatment while the highest seed weight loss and seed damage were obtained in the control. The study showed that C. chinense seed powder had higher activity against the test insect pest than A. melegueta seed powder. The two seed powders had high bio-activity against the insect and therefore could be used in formulating environment friendly plant-derived insecticide.  相似文献   

5.
[Objective]This study was conducted to obtain a new high-efficiency acaricide mixture.[Method]The synergism acaricidal of diafenthiuron and fenbutatin-oxide against carmine spider mite was investigated,and the optimal ratio of both acaricides were determined by means of co-toxicity factors and co-toxicity coefficients(CTC).[Result]At 24 h post-treatment,the LC50values of diafenthiuron and fenbutatin-oxide against T.cinnabarinus female adults were 154.67 and 93.26 mg/L,respectively,and the synergistic mass ratios of diafenthiuron and fenbutatin-oxide ranged from 1:0.06 to 1:0.87,and the optimal diafenthiuron-to-fenbutatin-oxide ratio was 1:0.39 with the LC50and CTC of 67.87 mg/L and 188.93(CTC significantly above 100 strongly indicated synergism),respectively,and the toxicity relative to diafenthiuron and fenbutatin-oxide was 2.28 and 1.37 times,respectively.[Conclusion]The joint acaricidal action of diafenthiuron and fenbutatin-oxide strongly indicates synergism.These findings proved scientific theoretical basis for mixing diafenthiuron and fenbutatin-oxide to control spider mites and developing a new synergisic acaricide.  相似文献   

6.
In this study, the activities of phenylalanine ammonia lyase (PAL), polyphenoloxidase (PPO), and peroxidase (POD) were assayed in cucumber seedlings (Cucumis sativus L.) at 0, 6, 12, 24, 48, 72, and 96 h after they were infested by Bemisia tabaci (Gennadius) using spectrophotometric analysis. The results indicated that herbivore infestation increased the activities of PAL, PPO, and POD. The enzymes showed different activity levels at different times after the infestation. The PAL activity reached the first high peak by 23.1% at 6 h and the highest peak by 29.1% at 48 h compared to the control. The PPO activity reached the first high peak by 22.7% at 6 h and the highest peak by 52.6% at 24 h, and the POD activity reached the highest peak by 213.2% at 6 h and another higher peak value by 135.2% at 96 h. The results suggest that the enhanced activities of the enzymes may contribute to bioprotection of cucumber plants against B. tabaci infestation.  相似文献   

7.
The 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester from neem oil was investigated for antibacterial activity against three bacterial strains viz., Staphylococcus aureus ATCC No. 25923, Escherichia coli ATCC No. 44102 and Salmonella sp. ATCC No. 50 041 in vitro. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of the 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester were determined by using the broth microdilution dilution (BMD) method at different concentrations ranging from 20 to 0.625 mg mL-1. Its time-inhibition curve against E. coli was also tested and showed that the MIC values for the bacterial strains S. aureus, E. coli and Salmonella sp. were 20, 5 and 10 mg mL-1, respectively. Its MBC values were 20, 20 and 10 mg mL-1, respectively. The antibacterial activity of 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester against three strain tested showed the relationship with time and concentration.  相似文献   

8.
9.
An allele of CYP6BQI3, named CYP6BQ 13v2 (GenBank accession no. FJ209361), was isolated from the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) by RT-PCR. The cDNA sequence of CYP6BQ13v2, 1 563 bp in length, contains an open reading frame of 1 554 nucleotides encoding a putative protein of 518 amino acid residues with a predicted molecular weight of 59.92 kDa and a theoretical pl of 7.60. The putative protein contains the classic hemebinding sequence motif F××G×××C×G (residues 456-465) conserved among all P450 enzymes as well as other characteristic motifs of all cytochrome P450s. It shares 98% identity with the previously published sequence of CYP6BQ13 (GenBank accession no. XP967146) from the T. castaneum genome project. Phylogenetic analysis of amino acid sequences from members of various P450 families indicated that there was closer phylogenetic relationship of CYP6BQ 13v2 with CYP302A1 and CYP307A1 mediating synthesis of the insect molting hormone, distant relationship with CYP6B1 metabolizing plant allelochemicals, CYP6D 1 linking to pyrethroid resistance and other members of CYP6 family. Expression test of the gene in the adults and immature stages of T. castaneum by quantitative real-time PCR revealed that CYP6BQ13v2 is expressed in all life stages investigated. The mRNA expression level in 1st instar larvae was 14.9- and 3.86-fold higher than those in pupae and adults, respectively. The CYP6BQ13v2 expression levels appeared in the order of 1st instar larvae, followed by 4th instar larvae, 7th instar larvae, adult, and pupae from high to low. The more bioinformation of CYP6BQ 13v2 was also analyzed.  相似文献   

10.
The methanol extract of Ficus sarmentosa var. henryi (King) Corner was found to detect potent inhibitory activities against 6 crop pathogenic fungi, Fusarium graminearum, Pumpkin fusarium Wilt, Curvularia lunata (Wakker) Boed, Septoria zeicola Stout, Botrytis cinerea, and Rhizoctonia solani. Four flavonoids were isolated from the extract of F. sarmentosa var. henryi by activity-guided fractionation and they were identified as eriodictyol (1), homoeriodictyol (2), dihydroquercetin (3), and luteolin (4) by spectroscopic means and displayed excellent inhibitory activity against F. graminearum and S. zeicola. Among them, luteolin (4) showed the strongest inhibitory activity with IC50 values of 56.38 and 81.48 mg L^-1, to the fungi, respectively. The in vitro inhibitory activity of F. sarmentosa var. henryi (King) Corner was reported for the first time and the inhibitory action mechanism of luteolin (4) was worthy of further research.  相似文献   

11.
The aim of this study was to determine the extraction technique of supercritical fluid carbon dioxide(SF-CO 2) for the essential oil from Inula britannica flowers and its antifungal activities against plant pathogenic fungi for its potential application as botanical fungicide.The effects of factors,including extraction temperature,extraction pressure,SF-CO 2 flow rate,flower powder size,and time on the essential oil yield were studied using the single factor experiment.An orthogonal experiment was conducted to determine the best operating conditions for the maximum extraction oil yield.Adopting the optimum conditions,the maximum yield reached 10.01% at 40°C temperature,30 MPa pressure,60 mesh flower powder size,20 L h-1SF-CO 2 flow rate,and 90 min extraction time.The antifungal activities of I.britannica essential oil using the SF-CO 2 against the most important plant pathogenic fungi were also examined through in vitro and in vivo tests.Sixteen plant pathogenic fungi were inhibited to varying degrees at 1 mg mL-1concentration of the essential oil.The mycelial growth of Gaeumannomyces graminis var.tritici was completely inhibited.The radial growths of Phytophthora capsici and Fusarium monilifome were also inhibited by 83.76 and 64.69%,respectively.In addition,the essential oil can inhibit the spore germination of Fusarium oxysporum f.sp.vasinfectum,Phytophthora capsici,Colletotrichum orbiculare,and Pyricularia grisea,and the corresponding inhibition rates were 98.26,96.54,87.89,and 87.35% respectively.The present study has demonstrated that the essential oil of I.britannica flowers extracted through the SF-CO 2 technique is one potential and promising antifungal agent that can be used as botanical fungicide to protect crops.  相似文献   

12.
In this research, convective and microwave drying characteristics, energy requirement and color changes of dill leaves (Anethum graveolens L.) were reported. Dill leaves were dehydrated in a computer connected parallel air flow type dryer and in a microwave oven dryer. Samples of freshly harvested dill leaves were dehydrated under three air temperatures of 50, 60 and 70 ℃, and at three microwave power levels of PL-1 (90 W), PL-2 (160 W) and PL-3 (350 W). Selected drying air velocity was 0.30 m/s for all temperatures. Dill leaves were dehydrated from the initial moisture content of 735 (percentage dry basis) to a final moisture content of 8%-10%. During convective drying experiment, products were weighted automatically by the balance per 5-10 min. Data were transferred to the computer and processed by software. During microwave drying, the products were weighted, and data were recorded manually per 15-60 min. The influence of drying method, drying air temperature and microwave power level has also been studied. Hunter L, a, b values system was also used to evaluate changes in total color difference (AE) on dried products. The results showed that convective drying air temperature and microwave oven power levels influenced the total drying time, total energy requirement, specific energy requirement and color difference for dill leaves. The minimum specific energy requirement was determined as 10.72 kWh/kg and 18.72 kWh/kg for 70 ℃ and PL-3, respectively. 70℃ drying air temperature and PL-3 were found to yield better quality product in terms of color retention of Hunter L, a, b and AE. As a result, to reduce drying energy consumption and to keep better color retention, convective drying can be recommended for this application.  相似文献   

13.
The present study was conducted to investigate antifungal activity ofLawsonia inermis (Henna plant). Leaf samples of the plants were collected from Eastern Nile of Khartoum state, Sudan. Ethanol and petroleum ether extracts in various concentrations were obtained by maceration (cold method). The extracts were bioassay in vitro to know their bioactivity to inhibit the growth of tested fungi. The cup plate agar diffusion method was adopted to assess the antifungal activity of the extracts against tested yeasts while agar incorporated method was used for other molds. Both extracts revealed anti fungal activity against all yeast strains except Pichiafabianii which was found resistant to both ethanol and ether extracts. The results displayed antifungal activity against tested fungi. Minimum mould concentration (MMC) of the extracts was determined. The obtained results revealed antifungal activity of henna leaves extracts which support the traditional use of the Henna in therapy of fungal infections. The possibility of therapeutic use of Sudanese henna as antifungal agents is recommended.  相似文献   

14.
In this study, the insecticidal active substance of the fruiting body of Paecilomyces cicadae (Miquel) Samson that can kill the larvae of Plutella xylostella (Lepidoptera: Plutellidae) was isolated and purified by combined separation with biology experiments for the first time. By means of bioactive guided isolation of 40% ethanol-H2O, dichloromethane, ethyl acetate, n-butyl ethanol, macroporous adsorption resin column, high performance liquid chromatography, and sephadex A-20 column, the insecticidal active compound was purified,and a white powder compound was obtained. The compound was active against the third instar larvae ofP. xylostella in 24, 48, and 72 h at the concentration of 10.0 mg mL-1 with a corrective mortality of (95.1 ± 1.8), (97.7 ± 1.6), and (99.1 ± 1.7)%, respectively. The compound was strongly sensitive to the larvae. It was stable at acid environment, and was not sensitive to pepsin, and other chracteristics were studied.  相似文献   

15.
Soybean meal hydrolyzate (SMH) has been proposed for use as a natural preemergence herbicide.However,the mechanism by which SMH exerts its herbicidal activity remains unclear.In this paper,the herbicidal activities of SMH against perennial ryegrass (Lolium perenne L.) under non-sterile and sterile conditions were evaluated and the relationship between the molecular weight of the ultrafiltration (UF) fractions of SMH and their herbicidal activities were investigated.Besides,the ammonia content changes of the media of SMH treatments 7 d after incubation were also analyzed.The results showed that SMH inhibited the radicle growth of germinating L.perenne seeds in a dose-dependent manner under non-sterile condition.However,SMH in the concentrations investigated increased the radicle length and shoot length by 14-17% and 11-15% respectively under sterile condition.The ammonia contents in the SMH media at all treatments increased greatly from less than 0.01 mg L-1 to up to 11.86-41.37 mg L-1 after 7 d incubation under non-sterile condition.However,ammonia content did not change under sterile condition,proposing that the herbicidal activity might be caused by the free ammonia released from SMH by microbial activity.There was no difference on the perennial ryegrass radicle inhibition among the UF fractions of SMH on an equivalent N basis.It could be concluded that SMH exerted its herbicidal activity through the free ammonia released under non-sterile condition instead of by specific peptide(s) in SMH.  相似文献   

16.
Bemisia tabaci is one of serious insect pests attacking vegetables and has been difficult to control using conventional insecticides. In the past 10 years, new insecticides have been introduced that provide a diversity of novel modes of action and routes of activity to effectively control whitefly. Consequently, intensive used of insecticides in vegetable cultivation has resulted in reduced susceptibility and develops resistance in agriculture industry. In controlling B. tabaci population, insecticides are the common method used by farmers. This study aimed to determine the most effective insecticide against B tabaci by using LC5o value. This study was conducted at the Crop Protection Laboratory, Faculty of Applied Science, Universiti Teknologi MARA Malaysia with the controlled room temperature of 24.33 ± 0.14℃ with dark and light ratio of 1:1 (12 hours: 12 hours) is an ideal condition for rearing the insect. The hypothesis of the study is to test if insecticides can control the nymph of whitefly. A total of 50 two-day-old nymphs were treated with insecticides using leaf-dip bioassay procedure. This experiment was replicated three times. The survival rates of the nymphs were analyzed using analysis of variance (ANOVA). Data on toxicity was analyzed by a special Probit Programme-Single Line Analysis based on Finney (1971). There was a significant difference (df = 8, F = 85.84, P = 0.000) in survival rate of nymph ofB. tabaci to eight insecticides tested. Among the insecticides tested, dimethoate, chlorpyrifos + cypermethrin and diafenthiuron showed significantly higher survival rate of nymph compared to other treatments. When LC50 values were compared for diafenthiuron which is less potent (LCs0 ---- 2.44), abamectin was found to be 3.44 times more potent than diafenthiuron, followed by esfenvalerate,acetamiprid, profenofos, chlorpyrifos + cypermethrin and dimethoate, and the least potent was deltamethrin. The toxicity of eight insecticides tested against nymphs was in the following  相似文献   

17.
18.
Sporamin is a soluble protein in sweet potato, and falls into two distinct homology groups, subfamilies A and B. In this research, a sporamin B was purified and its amino acid sequences, trypsin inhibitor activity (Ti activity) were analyzed. This sporamin B was isolated from sweet potato tubers [Ipomoea batatas (L.) Lam cv. 55-2] through extraction of the water-soluble fraction, dialysis, ultrafiltration and ion-exchange chromatography. Homology determined by polyacrylamide gel electrophoresis showed that mainly one bond appeared in gel after being reduced by SDS (sodium dodecyl sulfate), or by SDS and 2-mercaptoethanol, or in native situation. By comparing the data of the polypeptide mass Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry with those of the mass of the theoretical amino acid sequences from NCBI protein database, it was revealed that it was Q40091|Q40091_IPOBA, sweet potato sporamin B - Ipomoea Batatas (sweet potato) (Batate). The sequence coverage was 70.6%. N-terminal sequence was SETPV (Ser-Glu-Thr-Pro-Val). There is a linear relationship between trypsin inhibitor activity (Ti activity) and amounts of this sporamin B (3-18 μg mL-1). The equation of linear regression was y = 2.5809x + 17.049 (r2 = 0.9966). There was a curvilinear relationship between Ti activity and amounts of this sporamin B (21-150 μg mL-1). The equation of curvilinear regression is y = 14.417ln(x) + 23.26 (r2 = 0.9924). The concentration of sporamin B with Ti activity after heating at 40°C may induce part denature of this sporamin B, and there was no statistic difference after heating at 40, 50, 60°C for 20 min. Heat treatment at more than 90°C leads to a dramatic decrease of trypsin inhibitor efficiency. The results suggested that Q40091|Q40091_IPOBA was the major sporamin B in sweet potato tubers [Ipomoea Batatas (L.) Lam cv. 55-2], which had strong Ti activity, and was stable to both thermal and DTT (DL-dithiothreitol) relatively.  相似文献   

19.
臭牡丹叶提取液对2种植物病菌的抑制作用研究(英文)   总被引:1,自引:0,他引:1  
The test was undertaken to reveal the antifungal activity of extracts from Clerodendrum bungei leaves against Pestalotia funereal and Rhizoctonia solani,the results showed that optimal condition for best antifungal activity of extracts against Pestalotia funereal and Rhizoctonia solani are as follows:material-liquid ratio of 1∶6,75% ethanol as extracting solvent,reflux at 90 ℃ for 1.5 h.The substances with good dissolubility in ethanol and water solution such as organic acid,bioflavonoid and alkaloid are main antifungal bioactive substances in Clerodendrum bungei.  相似文献   

20.
The aim of this study was to determine the best extraction technique, the most suitable solvent, the optimal plant parts, and the acaricidal activities of Artemisia annua L. The petroleum ether (30-60℃), petroleum ether (60-90℃), ethanol, acetone, and water parallel and sequenced extracts were obtained from the leaves, stems and roots of different period of A. annua L. in April, May, June, July and September respectively. And then the acaricidal bioactivities against Tetranychus cinnabarinus of all extracts were determined by the slide-capillary method in the laboratory. The results indicated that the acaricidal bioactivities elevated as the development of A. annua plant at the concentration of 5 mg mL-L The general tendency exhibited the sequence of July 〉 June 〉 May 〉 April, but September decreased comparing to July. However, the most effective extracts in five months were all acetone parallel extract of A. annua leaf, and the corrected mortalities treated after 48 h ranged from 74 to 100%. The median lethal concentrations (LC50) against T. cinnabarinus of acetone parallel extracts ofA. annua leaves in September, July, June, May and April were 0.5986, 0.4341, 0.8376, 0.9443 and 1.3817 mg mL^-1, respectively, treated after 48 h. The 13 groups were isolated from acetone extracts ofA. annua leaves in July by column chromatography, both the 1 lth and 12th groups exhibited strong bioactivities. The median lethal concentrations of the 1 lth and 12th groups against T. cinnabarinus were 0.3683 and 0.1586 mg mL^-1, respectively. The acetone parallel extract ofA. annua leaf in July was the most toxic to T. cinnabarinus and the corrected mortality was 100% after 48 h. The acetone parallel extract of the 1 lth and 12th groupswere the most active components, acted as the emphases in further study.  相似文献   

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