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1.
以竹类热处理的副产物竹焦油为原料,柑桔为供试作物,选用60%竹焦油钠盐水剂、75%竹焦油钾盐水剂和50%竹焦油乳油,以20%三氯杀螨醇乳油为对照药剂,对柑桔全爪螨进行田间药效试验。结果表明:60%竹焦油钠盐水剂、75%竹焦油钾盐水剂对甘桔全爪螨的校正防效与对照药剂20%三氯杀螨醇乳油差异不显著,且不同浓度之间无显著性差异。50%竹焦油乳油药后3-7天防效均高于对照药剂,田间试验表明50%竹焦油乳油是一种良好的天然杀螨剂,对柑桔全爪螨具有较强的防治作用。  相似文献   

2.
精制竹醋液的安全性毒理学评价   总被引:1,自引:0,他引:1  
以精制竹醋液为材料,按食品安全性毒理学评价程序和方法(GB15193-94)进行了急性毒性、小鼠微核、小鼠精子畸形和Ames试验。结果表明,精制竹醋液对大、小鼠经口LD50雌雄均大于10.0 g.kg-1BW,属实际无毒,小鼠骨髓嗜多染红细胞微核、精子畸形和Ames试验检测均为阴性。证实了精制竹醋液接触人和动物皮肤及经口、鼻使用是安全可靠的。  相似文献   

3.
为测定氟吗啉原药对大鼠的急性吸入毒性,求出半数致死浓度(LC50),同时为亚慢性和其他毒理学研究中接触剂量的选择提供依据,参照《农药登记毒理学试验方法》,以中华人民共和国国家标准(GB15670-1995)为准则,用SD(Sprague Dawley)大鼠作为试验动物,对氟吗啉原药进行了急性吸入毒性试验。结果表明:氟吗啉原药对SD雌雄大鼠急性吸入毒性试验LC50均大于2093±30mg/m~3。根据GB15670-1995《农药登记毒理学试验方法》大鼠急性吸入毒性分类标准,氟吗啉原药大鼠急性吸入毒性为低毒,该结论可为安全使用提供依据。  相似文献   

4.
为搞清复合植物性鼠类不育剂对人畜的安全性,采用向SD大鼠经口灌胃不同剂量不育剂的方法,进行了急性毒性和长期毒性研究。结果表明:该鼠类不育剂属低毒(LD50为4640.3±127.1mg/kg),无明显致死作用,可列为毒性极低物质,可在控制鼠害中安全应用并大面积推广;但在高剂量下,对雌雄大鼠心脏功能、雄鼠肝功能和雄鼠血液相关指标中的极少数生化指标造成偏高或偏低的影响,应注意使用剂量不能过大,避免对生态环境造成不利影响。  相似文献   

5.
5种植物源农药对黄脊竹蝗毒力及毒饵的制备与防治效果   总被引:5,自引:5,他引:0  
为揭示5种植物源农药对黄脊竹蝗毒力强度,探寻制备诱杀黄脊竹蝗成虫新型毒饵的方法,采用碳酸铵、碳酸氢铵和氯化铵与5种植物源农药混合制备毒饵,并进行诱杀黄脊竹蝗成虫试验。结果表明:5种农药对黄脊竹蝗均有良好的致死作用,1%苦参·藜芦碱可溶液、1.2%烟碱·苦参碱乳油、0.5%藜芦碱可溶液、1.5%苦参碱可溶液和4%鱼藤酮乳油对黄脊竹蝗跳蝻和成虫的LC50依次为1.527、0.856、1.931、0.927、1.602 mg/L和1.767、0.957、2.176、1.126、1.825 mg/L;碳酸铵、碳酸氢铵和氯化铵水溶液可代替人尿作为引诱剂,其最佳浓度配比为70、80和90 g/L,5种植物源农药可代替化学药剂作为胃毒剂,胃毒剂与引诱剂的体积比:1.2%烟碱·苦参碱乳油和1.5%苦参碱可溶液均为1∶30,1%苦参·藜芦碱可溶液和4%鱼藤酮乳油均为1∶20,0.5%藜芦碱可溶液为1∶15。本研究提出的毒饵制备方法,可广泛用于大量诱杀黄脊竹蝗成虫,可为黄脊竹蝗的无公害防治乃至综合防治提供借鉴。  相似文献   

6.
6种植物源农药对竹斑蛾幼虫的毒力及应用分析   总被引:1,自引:1,他引:0  
为筛选有效控制竹斑蛾(Artona funeralis)幼虫的植物源农药,选用6种植物源农药开展室内毒力测定和林间防治效果分析。结果表明:6种植物源农药对竹斑蛾幼虫均有良好的致死作用。参试的植物源农药以1.2%烟碱·苦参碱乳油和1.5%苦参碱可溶液的毒力较强,0.4%蛇床子素乳油的毒力较弱;4%鱼藤酮乳油、1.2%烟碱·苦参碱乳油、0.4%蛇床子素乳油、1%苦皮藤素可溶液、碧绿1%苦参碱和1.5%苦参碱可溶液对竹斑蛾幼虫的LC50分别为0.826 mg/L、0.596 mg/L、1.016 mg/L、0.962 mg/L、0.811 mg/L和0.612 mg/L;林间施药4 d后,6种植物源农药的防治效果均超过90%;最佳田间施药浓度为:1.5%苦参碱可溶液和1.2%烟碱·苦参碱乳油均为1 500倍液,碧绿1%苦参碱和4%鱼藤酮乳油均为1 200倍液,0.4%蛇床子素乳油和1%苦皮藤素可溶液均为1 000倍液。参试的植物源农药对竹斑蛾幼虫的防治效果良好,可用于生产上防治竹斑蛾幼虫。  相似文献   

7.
用50%竹焦油乳油分别对水稻纹枯病、稻曲病和黄瓜白粉病进行田间药效试验表明,其防治效果为水稻纹枯病59.1%~74.1%,且使用浓度250、500倍的情况下,对其平均防效与5%井冈霉素WC200倍相当;防治稻曲病效果为56.3%~73.6%,250倍明显高于20%三唑酮EC1000的防治效果;防治黄瓜白粉病效果为63.6%~78.0%,在使用浓度250、500倍的情况下,对其平均防效优于0.3%多抗霉素AS 800倍处理。50%竹焦油用量以500倍为宜。因此,竹焦油EC对3种病原菌均有较好的防治效果是一种高防效低残留安全性好的新型广谱性杀菌剂。  相似文献   

8.
5种生物农药喷雾防治竹镂舟蛾幼虫效果评价   总被引:1,自引:1,他引:0  
为揭示无公害防控竹镂舟蛾的关键技术,在福建政和县选择竹镂舟蛾为害的毛竹林设立试验研究区,选用1.5%苦参碱可溶液、3%高渗苯氧威乳油、25%阿维·灭幼脲悬浮剂、1.2%烟碱·苦参碱乳油和1.8%阿维菌素乳油等5种生物农药,应用无人机喷雾技术,开展防治竹镂舟蛾幼虫用药的最佳使用剂量筛选试验,并检测竹林土壤和竹笋中的农药残留。结果显示:药后5 d,5种农药均有2个浓度水平对竹镂舟蛾幼虫的校正死亡率达86%以上;农药的最佳浓度水平(用纯净水以体积比稀释的倍数)是:1.5%苦参碱和1.2%烟碱·苦参碱均为1 500倍液,3%高渗苯氧威为2 500倍液,25%阿维·灭幼脲为1 000 倍液,1.8%阿维菌素为800倍液。在竹笋和土壤中均未检出所施的农药成分。研究结果表明,试验的5种农药对竹镂舟蛾幼虫致死作用强、防效好,且不会产生农药残留,竹林喷施这5种农药,可大幅降低竹镂舟蛾幼虫的虫口数量,达到无公害防控竹镂舟蛾成灾的目的。  相似文献   

9.
2种植物源农药烟雾对黄脊竹蝗的防治效果   总被引:2,自引:2,他引:0  
为试验喷烟施放1.2%烟碱·苦参碱乳油和1.3%苦参碱可溶液对黄脊竹蝗的防治效果,确定其最佳应用浓度及药剂用量,在福建省三明市梅列区的灰竹林中开展喷烟防治试验。试验结果表明:施药后4 d,1.2%烟碱·苦参碱乳油和1.3%苦参碱可溶液2种农药对黄脊竹蝗成虫的防治效果均超过86.7%,最佳应用浓度配比均为农药与烟雾剂的容积比为1:7,药剂最佳用量分别为900 mL/hm2和1 050 mL/hm2。喷烟施放2种植物源农药对黄脊竹蝗成虫的致死作用强、防治效果佳,可在生产中用于防治工作。  相似文献   

10.
采用常规方法研究牡丹江锗啤酒的急性毒性实验,亚急性毒性实验,LD50测定和过敏试验。研究结果表明:无毒性、不致敏,长期口服对心、脑、肝、肾组织无毒性,LD50测定:锗啤中Ge-132LD50为2·48mg/kg,表明无毒、安全,可长期饮服。  相似文献   

11.

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.  相似文献   

12.

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.  相似文献   

13.

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.  相似文献   

14.

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.  相似文献   

15.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。  相似文献   

16.

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.  相似文献   

17.
18.

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.  相似文献   

19.
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.  相似文献   

20.
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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