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51.
研究了溴氰菊酯和吡虫啉在甘蓝中残留的仪器检测方法,并在天津、山东和江苏连续开展了2 a溴氰菊酯和吡虫啉在甘蓝中残留状况和消解动态规律研究的田间试验。结果表明,在溴氰菊酯和吡虫啉的添加质量比分别为0.025~0.5 mg/kg和0.025~1 mg/kg的水平下,甘蓝中溴氰菊酯的平均添加回收率为92.19%~102.48%,变异系数为2.98%~9.46%;吡虫啉平均添加回收率为94.58%~100.30%,变异系数为0.85%~4.10%。甘蓝中溴氰菊酯和吡虫啉的最小检出量分别为0.1 ng和0.5 ng,甘蓝中溴氰菊酯和吡虫啉的最低检出质量比均为0.025 mg/kg。田间试验表明,在甘蓝莲座期施用20%溴氰菊酯.吡虫啉悬浮剂1次,溴氰菊酯和吡虫啉在甘蓝中的消解动态符合一级动力学反应模型,溴氰菊酯和吡虫啉在甘蓝中的残留消解半衰期分别为4.4~8.8 d和5.9~8.6 d。按照推荐剂量和1.5倍推荐剂量在甘蓝中施用20%溴氰菊酯.吡虫啉悬浮剂3~4次,2次施药间隔7 d,距最后一次施药10 d时,溴氰菊酯在甘蓝中的最高残留量低于GB2763—2005《食品中农药最大残留限量》规定的溴氰菊酯在甘蓝中的最大残留限量(0.5 mg/kg),以及NY 1500.5.6—2007《农产品中农药最大残留限量》规定的吡虫啉在甘蓝中的最大残留限量(1 mg/kg)。 相似文献
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边坡生态防护用灌木植物耐旱性试验研究与应用 总被引:1,自引:0,他引:1
本论文针对我国公路各地野生植物资源的开发利用水平还较低的实际情况,低品味的掠夺式索取,严重地影响了野生植物资源的自然更新和可持续利用。通过优选六种野生植物进行试验,对胡颓子(Elaeagnus bockiiD iels)、三颗针(Berberis julianae Schneid)、金丝梅(Hypericum patulum Thum b)、十大功劳(Mahonia fortunei(B ind l)Fedde)、刺梨(Rosa roxburghiiTrau)和火棘(Pyracantha fortuneana(M axim)L i.)等六种野生灌木为研究材料的水分对渗透调节物质,电导率,丙二醛,叶绿素含量,光合性状等影响进行了研究。分析了干旱胁迫下六种野生植物的生理生化指标的变化情况,对六种野生植物抗旱性强弱进行了综合评价,研究成果应用于四川省二郎山至康定段公路,降低了公路绿化后期养护成本。 相似文献
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Magdalena Gucia Grażyna Jarzyńska Anna K. Kojta Jerzy Falandysz 《Journal of environmental science and health. Part. B》2013,48(2):81-88
Mature specimens of Parasol Mushroom were collected annually in the outskirts of the Siemiany (2000–2003) and Rafa (2001–2003) sites in the northern part of Poland to examine temporal variations and similarities in the composition of 20 chemical elements. Analysis was done under the same condition and using well-validated analytical methods. Elements were determined by inductively coupled plasma–atomic emission spectroscopy and cold vapour–atomic absorption spectroscopy (Hg). The ranges of Ag, Al, Ba, Ca, Cd, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn concentrations in the caps of fruiting bodies were similar (p > 0.05; Mann-Whitney U test) for both geographically distant sites, and these specimens from Rafa were more contaminated with Pb (p < 0.05; Mann-Whitney U test). The annual collections of caps in the Siemiany site varied in Ag, Al, Ba, Ca, Cd, Co, Cu, Fe, Hg, Na, Rb and Sr and contents (0.05 < p < 0.001), while they were similar in Cr, K, Mg, Mn, Ni, P, Pb and Zn (p > 0.05; Mann-Whitney U test). The annual collections of specimens from the Rafa site varied in contents of Ag, Al, Ba, Ca, Fe, Hg, K, Mg, Mn, P, Rb and Zn (p > 0.05), while they were similar in Cd, Co, Cr, Cu, Na, Ni, Pb and Sr (p < 0.05). The results of this study imply that metallic elements content of Parasol Mushroom collected at the same undisrupted sites, and hence keeping the same geochemical condition for mushroom development and fructification (the same stands and probably the same mycelia), can fluctuate over the years or the life-span of mycelium. Hence, when assessing the nutritional value of essential metallic elements and status of non-essential or toxic metallic elements in Parasol's Mushroom caps (and probably also of other mushrooms species) to man, the possible fluctuation in contents over time have to be taken into account. 相似文献
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采用土培试验与化学分析方法研究了3种野生植物汁液对绿豆和玉米生长的营养效应。结果表明,野生植物汁液提高绿豆植株干重、根系活力、磷含量和叶绿素含量,以C汁液对植株干重提高量最大,达165%~260%;B、C汁液提高绿豆根系活力254%~1102%。3种野生植物汁液处理的玉米植株干重差异不明显,但却显著提高根系活力和过氧化氢酶活性。 相似文献
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西藏色季拉山野生观赏树木资源及其开发利用 总被引:5,自引:0,他引:5
西藏色季拉山区野生观赏树木资源丰富,有40科75属190余种。种类最多的科是蔷薇科、杜鹃花科、忍冬科、虎耳草科和豆科。种类最多的属是杜鹃花属、忍冬属、李属、绣线菊属和子属。其中花木占47.6%,花果木占24.6%,果木占11.0%。花木中白花者占46.4%。果木中红果者占80.9%。75.3%的种类生于森林型生境。74.4%的花木夏季开花。生于阳生灌丛型生境的种类最易被驯化。黄牡丹、多蕊金丝桃、小叶子、素馨花和巨柏等应首先开发。 相似文献
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Autotoxic effects of essential oils on photosynthesis in parsley, parsnip, and rough lemon 总被引:3,自引:0,他引:3
Summary. Many plant species contain essential oils with allelochemical properties, yet the extent to which these same chemicals can be autotoxic is unclear. In this study, we tested the toxicity of several essential oil components to three species that produce them—Pastinaca sativa and Petroselinum crispum (Apiaceae), and Citrus jambhiri (Rutaceae). The effects of exogenous application of small amounts of essential oil components to the surface of foliage, followed by a pinprick to allow entry into the leaf, were monitored by chlorophyll fluorescence imaging. Rapid and spatially extensive declines in photosynthetic capacity were detected within 200 s. The most toxic constituents were monoterpenes. Two sesquiterpenes, caryophyllene and farnesene, and the phenylpropanoid myristicin, by comparison, were not toxic. Autotoxicity of endogenous essential oil was investigated by slicing through containment structures (glands or tubes); significant toxicity, manifested by reduced photosynthetic activity, was observed in all three species but was most pronounced in P. sativa and P. crispum, both of which possess oil tubes. 相似文献