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1.
The effects of Neemgard, an acaricidal and fungicidal formulation obtained from neem (Azadirachta indica) seed kernels, on the phytophagous miteTetranychus cinnabarinus, the predacious mitePhytoseiulus persimilis, and the predatory spiderChiracanthium mildei, were investigated in laboratory experiments. Neemgard was highly toxic toT. cinnabarinus but had no toxic effect onC. mildei orP. persimilis. Another neem formulation—the insecticidal Neemix 45—caused conspicuous repellency, but no mortality, inT. cinnabarinus. 相似文献
2.
The antimicrobial effects of extracts of neem seed (Azadirachta indica A. Juss.) were investigated using microbial growth inhibition assays. A laboratory-prepared neem seed extract along with
a commercially available formulated product, were characterized using HPLC, and shown to be effective against a range of bacteria
in an agar diffusion assay. The active ingredient,i.e., the unformulated seed extract of the commercial product, also showed activity and this was further investigated in a biochromatogram,
using the sensitive bacteriumBacillus mycoides. Results showed antibacterial activity as three discrete inhibition zones that did not correspond to the Rf of the major neem metabolites, azadirachtin, nimbin and salannin. This suggests that these compounds were not antibacterial.
The colony radial growth rates of the fungal pathogens that cause ‘take-all’ and ‘snow mould’ disease were both significantly
affected when the commercial, unformulated, neem seed extract was incorporated into the growth medium. Experiments in liquid
culture suggested that the effect was fungistatic. Conidial germination of the commercially important obligate pathogenSphaerotheca fuliginea (powdery mildew) was reduced to 11%. The results show that neem seed extracts possess antimicrobial activity with notable
effects on some fungal phytopathogens. This Work demonstrates that neem seed extracts have potential for controlling both
microbial and insect pests.
http://www.phytoparasitica.org posting Sept. 16,2001. 相似文献
3.
Rajendra Prasad 《Archives of Agronomy and Soil Science》2013,59(4-5):447-454
Field experiments were made on a sandy clay loam soil at the Indian Agricultural Research Institute, New Delhi to study the effect of levels and sources of nitrogen on concentration and uptake of nitrogen by a high yielding variety Pusa 834 and a hybrid PRH3 of rice. Nitrogen concentration in hybrid PRH 3 remained lower than in Pusa 834, but N uptake was significantly more in the hybrid PRH 3. Nitrogen fertilization increased N concentration as well as N uptake by rice. At 30 days after transplanting (DAT) N uptake was more in Pusa 834, but at 60 DAT and at harvest hybrid PRH 3 recorded significantly more N uptake than Pusa 834. Use of neem oil blended urea (PNGU) and neem coated urea (NCU) increased N concentration and uptake by rice in both Pusa 834 and hybrid PRH 3. Use of neem coated/blended urea is recommended for rice. 相似文献
4.
1%苦参碱·印楝素EC（托盾）,防治茶树害虫茶小绿叶蝉、茶毛虫、茶尺蠖均有较好防治效果,可以大力在郴州市茶叶绿色食品、有机茶产区推广应用,喷施浓度以托盾800倍液为好。 相似文献
5.
阿维菌素与印楝油对柑桔红蜘蛛的增效作用 总被引：1，自引：0，他引：1
室内测定阿维菌素与印楝油对柑桔红蜘蛛的毒力及其复配组合的联合作用。毒力测定结果表明,阿维菌素与印楝油对柑桔红蜘蛛雌成螨处理后24 h的LC50分别为0.01 μg/mL 和6 579.87 μg/mL。以共毒因子法评价阿维菌素与印楝油6种复配组合的联合作用,结果显示,二者以1 ∶ 100和1 ∶ 125两种比例复配对柑桔红蜘蛛雌成螨的共毒因子分别为24.50和31.08,具增效作用;进一步以共毒系数法确定阿维菌素与印楝油以1 ∶ 125的比例复配增效作用最为显著,共毒系数为160.76。 相似文献
6.
Four neem-based insecticides, Neemix® (0.25% EC @ 20 mg azadirachtin/liter), Ecozin® (3% EC @ 20 mg azadirachtin/liter), Agroneem® (0.15% EC @ 4.8 mg azadirachtin/liter) and Neem oil (0.25% EC azadirachtin @ 20 mg azadirachtin/liter) and a non-commercial neem leaf powder, were evaluated for oviposition deterrence, antifeedant effect to larvae and toxicity to eggs and larvae of Pieris brassicae (Linn.) on cabbage leaves in the laboratory. The concentrations tested were with in the ranges of recommended field rates. Oviposition deterrence in no-choice, two-choice and six-choice assays, was observed for all the treatments. They exhibited significant (P < 0.01) oviposition deterrence on P. brassicae when compared with a non-treated control. Cabbage leaves treated with the neem-based insecticides were used as an egg-laying substrate. Numbers of eggs oviposited by P. brassicae adults on treated cabbage leaves were significantly lower then those treated with water, but no significant differences were detected among the neem insecticides. They also deterred feeding by Pieris larvae and exhibited significant antifeedant effects. Larvae of P. brassicae on treated leaves stopped feeding and dropped from the leaf, resulting in no or minimal damage. Direct contact with neem-based insecticides decreased the survival of eggs. Survival of larvae fed for 9 days on leaves treated with neem-based insecticides was reduced to 51%, 49%, 48%, 24% and 18% in the Neem oil, Neemix, Agroneem, Ecozin and neem leaf powder treatments, respectively. Therefore, it can be concluded from the present investigations that neem-based insecticides had oviposition deterrence, antifeedant and toxic effect to P. brassicae. 相似文献
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8.
Yu-Qun Zhang Jiao Xu Zhong-Qiong Yin Ren-Yong Jia Yang Lu Fan Yang Yong-Hua Du Ping Zou Cheng Lv Ting-Xiu Hu Shu-Liang Liu Gang Shu Geng Yi 《Fitoterapia》2010
From a petroleum ether extract of neem oil (Azadirachta indica A. Juss) the new tetrahydrofuranyl diester 1 was isolated as an anti-bacterial constituent. 1 showed significant activities against three standard bacterial strains, including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enteritidis CMCC (B) 50041. 相似文献
9.
试验结果表明,嚏施0．3％绿晶印楝素杀虫剂防治甜菜甘蓝夜蛾防效达74．8%-93．2％,高于速克毙,甜菜根产量提高29．4％。 相似文献
10.
Abstract Adults and immatures of the filbert aphid, Myzocallis coryli (Goetze), a major pest of hazelnuts worldwide, were exposed to foliage treated with different concentrations of a botanical insecticide, Margosan-O, derived from extract of neem seeds. Both mature and immature stages were highly sensitive to this compound. Acute toxicity causing immediate mortality of young nymphs, particularly at higher rates (50 ppm or more), and chronic effects resulting in reduced offspring production, lengthening of nymphal development time and reduced survival of subsequent generation were recorded. The offspring production of adult aphids fed on treated leaves was reduced in a dosage-dependent manner, nearly 50% at 2.5 ppm to over 80% at 62.5 ppm. However, no nymphal survival was recorded at 25 ppm or higher doses. A repellency effect was also recorded, butthe feeding deterrence response was weak at best. Field trials also showed a marked reduction of aphid numbers on treated foliage, suggesting the effectiveness of neem against this major pest of hazelnuts. 相似文献