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丙线磷用于防治各种线虫、地下害虫,对对防治稻瘿蚊效果显著。丙线磷的气相色谱分析方法,国内报道的不多。本文介绍采用气相色谱法对丙线磷有效成分进行定量分析。 相似文献
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一、前言 甲基异柳磷是具有触杀和胃毒作用的高效广谱性有机磷杀虫杀线虫剂,主要用于防治地下害虫、线虫、桃小食心虫及其它鳞翅目害虫。 甲基异柳磷的合成一般采用水杨酸异丙酯与甲基二氯化物反应,再与异丙胺酰胺化反应而制得。我们采用相转移催化的方法进行合成,获得了较为满意的结果。 相似文献
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为评价肿柄菊粗提物毒杀线虫的潜力,利用石油醚、乙酸乙酯、二氟甲烷浸泡粉碎的肿柄菊枝叶混合物,经旋转蒸发获得粗提物,通过浸渍法检测了不同粗提物的毒杀线虫活性。结果表明:当浓度为10mg·mL^-1时,石油醚、乙酸乙酯和二氟甲烷粗提物24~72h内对线虫的毒杀效果较弱;当浓度为20mg·mL^-1时,二氯甲烷粗提物毒杀线虫活性最好,处理72h的线虫校正死亡率可达50.6%,乙酸乙酯粗提物和石油醚粗提物毒杀线虫活性均较弱;当浓度为40mg·mL^-1时,毒杀线虫活性大小依次是乙酸乙酯粗提物〉石油醚粗提物〉二氯甲烷粗提物,其中乙酸乙酯粗提物处理72h的线虫校正死亡率达73.6%。表明,对肿柄菊粗提物进行合理的处理、分离、纯化,有望开发出高效低毒、绿色环保的新型杀线虫农药。 相似文献
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每年植物寄生线虫在全球农业上造成的损失估计高达1000亿美元。这些线虫的寄生性是绝对的,它们必须生活在活的植物体内才能发育和繁衍。由于它们的主要生态小环境是在土壤内,所以线虫对植物造成的损害时常不被认知。大多数植物寄生性线虫侵染植物的根或其他地下部分,如鳞茎和块茎,并干扰植物吸取水份和营养物质。被线虫侵染的植物的表症通常类似缺乏水份和营养,如植物矮小、失绿、萎蔫下垂等。但是,有些线虫还可能侵染植物的地上部分。线虫除了对植物造成直接危害以外,某些线虫还能传播植物病毒。其他的病原物,如真菌和细菌,可以容易地从线虫侵入时造成的伤口侵入。另有报道,线虫的侵染还可能破坏寄主植物对真菌病原物的抗性。 相似文献
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诺氟沙星(NOR)环境残留会造成一系列生态和环境问题,而高级氧化技术可有效降解废水中的抗生素,但可能产生毒性更强的降解产物。选择秀丽隐杆线虫(C.elegans)作为受试生物,考察NOR氧化降解液对其生理、生化和分子指标的影响,并通过定量结构活性关系预测NOR及其降解产物毒性。结果表明,NOR降解液会刺激线虫运动行为,抑制其生长发育,而对活性氧自由基(ROS)和细胞凋亡无显著影响。然而,线虫氧化应激和神经毒性相关基因表达显著提高,表明造成氧化应激反应,线虫体内ROS被防御机制清除;线虫运动神经受损,进而导致其运动行为异常。毒性预测结果表明,哌嗪环裂解产物是主要毒性物质。 相似文献
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多功能大豆重迎茬专用肥的研究与应用 总被引:1,自引:0,他引:1
针对造成重迎茬大豆减产的两个主要原因 ,即以大豆孢囊线虫为主病虫危害及耕层土壤速效钾、速效锌、有效硼单一消耗 ,而研制开发的肥药结合多功能大豆重迎茬专用肥 (10 - 12 - 8)可显著提高单产 ,改善品质 ,抑制大豆孢囊线虫、根腐病及地下害虫的危害 ,满足重迎茬大豆不同生育阶段对 N,P,K,Mg等大中量及 Zn,B,Mn等微量营养元素的需要。试验示范结果表明 :大豆重迎茬专用肥比农民习惯施肥 (磷酸二铵 +尿素 +氯化钾 )平均增产2 3.5 % ,增产 385 .5 kg/ hm2 ,增收 6 15 .6元 / hm2 ,比等量的磷酸二铵增产 7.8% ,增产 177.1kg/ hm2 ,增收 2 40元 /hm2 相似文献
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在BB肥中加入中、微量元素的必要性 总被引:1,自引:0,他引:1
在BB肥中加入中、微量元素是测土配方施肥的需要。阐明了BB肥中加入中、微量元素的必要性、有效性、合法性以及对土壤和农作物的针对性,加入中、微量元素的BB肥可提高肥料利用率,提高农作物的产量和品质,减少病害的发生,具有广阔的发展前景。 相似文献
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Results are presented from five years (1990–1995) of a field leaching experiment on a sandy soil in south-west Sweden. The aim was to study N leaching, change in soil organic N and N mineralization in cropping systems with continuous use of liquid manure (two application rates) and catch crops. N leaching from drains, N uptake in crops and mineral N in the soil were measured. Simulation models were used to calculate the N budget and N mineralization in the soil and to make predictions of improved fertilization strategies in relation to manure applications and changing the time for incorporation of catch crops. In treatments without catch crops, a normal and a double application of manure increased average N leaching by 15 and 34%, respectively, compared to treatment with commercial fertilizer. Catch crops reduced N leaching by, on average, 60% in treatments with a normal application of manure and commercial fertilizer, but only by 35% in the treatment with double the normal application rate of manure. Incorporation of catch crops in spring increased simulated net N mineralization during the crop vegetation period, and also during early autumn. In conclusion, manured systems resulted in larger N leaching than those receiving commercial fertilizer, mainly due to larger applications of mineral N in spring. More careful adaptation of commercial N fertilization with respect to the amounts of NH4-N applied with manure could, according to the simulations, reduce N leaching. Under-sown ryegrass catch crops effectively reduced N leaching in manured systems. Incorporating catch crop residues in late autumn instead of spring might be preferable with respect to N availability in the soil for the next crop, and would not increase N leaching. 相似文献
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J. J. Neeteson 《Nutrient Cycling in Agroecosystems》1990,26(1-3):291-298
In the Netherlands, current nitrogen fertilizer recommendations for arable crops are based on the amount of soil mineral nitrogen in early spring. The larger the amount of soil mineral nitrogen, the lower the recommended application rate of fertilizer nitrogen. A more refined method is to draw up a balance sheet in which the nitrogen requirement of the crop is given on the one side and the contributions of fertilizer nitrogen, soil mineral nitrogen, and the amount of nitrogen mineralized during the growing period on the other. The most refined method of nitrogen fertilizer recommendation is the use of a simulation model that predicts the daily crop nitrogen requirement and nitrogen supply to the crop from various pools during the growing period. A simulation model thus adds the time element to nitrogen fertilizer recommendations. Moreover, in contrast with the other two methods, a simulation model allows identification of environmental side-effects of nitrogen fertilizer application.The current Dutch nitrogen fertilizer recommendations aim at predicting the economically optimum application rate of fertilizer nitrogen. From the environmental point of view it is interesting to know how much soil mineral nitrogen has accumulated in the soil at harvest, because this nitrogen is a potential loss to the environment through nitrate leaching during the subsequent winter period. If the economically optimum application rate of fertilizer nitrogen is applied to arable crops, it is unlikely that soil mineral nitrogen accumulates, except in the case of potatoes. Model calculations have shown that accumulation of soil mineral nitrogen after potatoes can be prevented when the recommended nitrogen application rate is reduced by 25%. In that case tuber yield is reduced by only 2%. 相似文献
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盲目过量施肥的危害及新型肥料的开发 总被引:6,自引:0,他引:6
针对当前盲目过量施肥所引起的少数地区环境污染,浪费化肥资源,造成土壤和作物营养元素失调,影响作物增产增收,降低作物品质等问题,论述了开发新型肥料及采用科学施肥方法提高化肥利用率的途径。最后,提出了若干建议和意见。 相似文献
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