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1.
利用人工选育的方法 ,获得了棉铃虫对辛硫磷的抗药性品系和相对敏感品系 ,其对辛硫磷的LD50分别为 1 1 .0 574μg/虫和 0 .9790 μg/虫。以生物测定与生化测定的方法 ,比较了两品系的差异。增效剂活体试验测定结果表明 ,磷酸三苯酯、增效磷对棉铃虫三龄幼虫均表现出一定的增效作用 ,但在两品系间的增效作用存在差异 ,对相对敏感品系的增效倍数分别为 2 .2 7倍、2 .1 3倍 ,对抗性品系的增效倍数分别为 6.93倍和 6.43倍。磷酸酯酶活性测定结果表明 ,抗性品系的酶活力分别是相对敏感品系的1 6.67倍 (碱性 )和 1 .89倍 (酸性 ) ,Km 和Vmax则分别为 0 .76倍、2 .64倍 (碱性 )和 1 .38倍、1 .78倍 (酸性 ) ;而羧酸酯酶的活性则差异不大。对靶标酶乙酰胆碱酯酶的活性测定表明 ,与相对敏感品系相比 ,抗性品系酶活性显著增强 ,并且对杀虫剂的亲和力降低 ,说明乙酰胆碱酯酶在棉铃虫对辛硫磷的抗药性中也有着重要的作用  相似文献   

2.
研究了木那格葡萄快速繁殖并确定了木那格葡萄愈伤组织诱导和继代的适宜条件。将木那格葡萄种子无菌处理,获得无菌幼苗,以单芽茎段为外植体,对木那格葡萄快速繁殖条件进行优化;以叶片为外植体,确定愈伤组织诱导和继代的适宜条件。结果表明:使用70%乙醇灭菌30s,0.1%升汞灭菌3min,使用浸湿的滤纸培养,适宜木那格葡萄种子萌发,萌发率为70%;适宜单芽茎段不定芽再生的培养基为B5 6-BA 0.05mg/L IBA 0.3mg/L 蔗糖30g/L,不定芽增殖倍数为1.25;适宜不定芽生根的培养基为B5 IBA 0.2mg/L 蔗糖30g/L,平均单芽生根数为5.09,平均根长2.97cm;适宜愈伤诱导的培养基为B5 6-BA1.5mg/ L NAA 0.2mg/L 蔗糖30g/L,愈伤诱导率为100%;适宜愈伤继代的培养基为B5 6-BA 1mg/L 2,4-D 0.1mg/L 蔗糖30g/L。  相似文献   

3.
王文丽  毕富春 《昆虫知识》1996,33(6):345-347
测定了T-751(O-甲基-O-苯基-S-正丙基硫代磷酸酯)对4种害虫的杀虫活性。结果表明,T-751对东方家蝇、豆蚜和二斑叶螨的LD50分别为0.42、70.5、4.20mg/L。T-751对东方家蝇的杀虫活性要比杀螟硫磷高11倍。在剂量分别为2.95,7.37mg/m2时,该药对东方家蝇和美洲大蠊的KT50分别为13.57和30.83分钟。  相似文献   

4.
通过细菌培养液DD值测量和平板计数技术观察不同物质对大肠杆菌生长的影响;对微量元素、稀土元素、动、植物激素、细菌提取物、真菌提取物、藻类提取物、植物提取物和动物提取物等13大类120余种物质在一定浓度范围的促大肠杆菌生长作用进行了观察。海带水提液和酵母提取物对大肠杆菌生长具有明显的促进作用;两的最佳作用浓度分别为20g/L和2%,DD值最大可分别达到对照组的2.93倍和5.06倍;平板计数可达3.94倍和5.39倍。  相似文献   

5.
SV1是一种增效范围较广的农药增效剂,对多种杀虫剂具有增效作用。经室内毒力测定.与敌百虫混用对棉铃虫、粘虫和二化螟的增效比值分别为2.93倍、2.43倍和2.7倍;与氧化乐果、久效磷和氰戊菊酯混配对棉蚜、褐稻虱和萝卜蚜的增效比值分别为1.63—10.67倍。杀虫毒力随着加入SV1成分的增加而提高,一般常用农药与SV1混配之比需要1:3以上才明显增效。防治钵栽棉蚜通过系统观察,在防治效果相仿情况下,SV1可使氧化乐果药效延长9天,久效磷药效延长7天,氰戊菊酯药效延长6天以上。SV1可以成为生产上与有机磷及拟除虫菊酯类杀虫剂混用的增效剂优势品种。  相似文献   

6.
柳杉毛虫防治试验研究   总被引:3,自引:0,他引:3  
用白僵菌、苏云金杆菌、2 4 .5 %全力、2 0 %氰戊菊酯等 4种杀虫剂的不同浓度对柳杉毛虫 (Dendrolimushoui L ajonquiere)进行室内毒力测定和林间防治试验 ,结果表明 ,野外防治柳杉毛虫以氰戊菊酯 6 0 0 0倍液 +苏云金杆菌 1.4× 10 9n/ ml+全力 80 0 0倍液 +白僵菌 1.2× 10 8n/ ml林间喷雾效果最佳 ,杀虫效果达 90 %以上。应用该复合剂大面积防治 2 0 hm2 ,效果达 80 %以上。  相似文献   

7.
陈达荣  吴清正 《昆虫知识》1992,29(4):213-214
室内毒力测定结果表明,叶蝉散与杀虫双混配剂对稻褐飞虱表现有增效作用。其中以1:1混配剂增效作用较为明显,共毒系数为175.6,增效倍数约为1.8倍;1:2和1:3混配剂的共毒系数分别为150.7和137.3,增效倍数约为1.5倍和1.4倍。从而为叶蝉散与杀虫双混剂的开发提供了科学依据。  相似文献   

8.
孙伟  林刚  罗杰  何光源 《生物技术》2004,14(4):53-56
以陈年小麦离体胚为外植体,MS培养基为基本培养基,附加5种植物生长物质2,4-D、NAA、KT、6-BA、GA3进行单因子和正交试验,研究植物生长物质在陈年小麦离体胚萌发中的作用。单因子试验结果表明:单独使用6-BA 1.0mg/L、GA3 2.5mg/L均能在一定程度上促进陈年小麦离体胚出芽和生根,出芽率分别为70.0%和77.5%,比对照分别提高了21.7%和29.2%;生根率分别为63.3%和72.2%,比对照分别提高了21.3%和30.2%。正交试验结果显示GA3对陈年小麦离体胚的萌发影响显著,最佳植物生长物质组合为2,4-D2.0mg/L NAA 1.1mg/L 6-BA0.5mg/L GA3 4.0mg/L,出芽率为82.5%,生根率为60.0%,比对照分别提高了32.5%和17.5%。  相似文献   

9.
研究了在蜜蜂毒致炎模型中虎纹镇痛肽 (HWAP I)的镇痛作用 .HWAP I有 6个剂量组 (n =10 ) ,分别为 0 .1、1、10、2 5、5 0、75 μg/kg .生理盐水作空白对照 .从 10 μg/kg开始不同剂量组表现不同程度的镇痛效果 (P<0 .0 5 ) ,且有一定的量效关系 ;同时用 2 5 μg/kg芋螺毒素SNX III做阳性对照 ,结果表明 2 5 μg/kgSNX III的镇痛效果介于 2 5 μg/kg与 5 0 μg/kgHWAP I之间 .计算得到HWAP I在给药后 1h半有效剂量ED50 大约是 30 μg/kg .  相似文献   

10.
苏云金芽孢杆菌发酵上清中增效物质生成的相关研究   总被引:2,自引:1,他引:1  
利用BIOSTAT ?-CL1 5L全自动发酵罐和 2 0t不锈钢发酵罐 ,对苏云金芽孢杆菌不同菌株 (GC-91 ,MP342 ,HD-1 )发酵上清液中增效物质的生成进行了研究 ,发现增效物质于对数生长期前期开始产生并积累 ,至对数生长期末期达到高峰 ,并保持稳定 ;不同菌株的发酵上清中增效物质生成量不同 ,其中GC-91最强 (增效倍数f=6.0 ) ,MP342次之 (f=3.7) ,HD 1最弱 (f=1.5 ) ;GC-91菌株上清液中增效物质生成曲线与晶体含量 ,效价代  相似文献   

11.
Simple biochemical means were used to enhance the endotoxin effect ofBacillus thuringiensis Berliner through optimization of conditions present in the insect gut required for release of intoxicating fragments from nonpoisonous intact endotoxin. This was achieved through the addition of either alkaline compounds naturally occurring in the insect midgut, general proteolytic activators or midly toxic compounds of inorganic (e.g. borax) and organic (e.g. tannic acid) nature along with endotoxin in the diet. A marked increase in the potency ofB.t. vars.entomocidus HD-635 andaizawai HD-133 againstSpodoptera littoralis (Boisduval) was obtained in the presence of 0.5% concentration of potassium carbonate. On the other hand, sodium carbonate was less effective at the tested concentrations. Among the tested proteolytic activators, the effect of magnesium ion was proportional to the concentration of the incorporated salt. Thus the potencies of δ-endotoxin preparations of HD-635 and HD-133 were increased 2–3 times after the addition of 1% concentration of magnesium chloride. A lesser effect was noted at 0.5%, whereas virtually the potency did not change at 0.25% concentration of the salt. Similar trends were noted with the incorporation of calcium chloride along with the endotoxin in the insect diet. The addition of sodium borate or tannic acid was highly effective in enhancing the potency of the tested sporeδ-endotoxin preparations with 2–4 fold increase.  相似文献   

12.
种植转Bt基因水稻对土壤酶活性的影响   总被引:42,自引:8,他引:34  
转Bt基因及非Bt基因水稻的盆栽试验研究表明,转Bt基因水稻在生长发育过程中可以向土壤中释放杀虫晶体蛋白,而且杀虫晶体蛋白的释放量与水稻生长发育时间有关;与非Bt基因水稻相比,转Bt基因水稻生长15d时,土壤脲酶活性显著下降(降幅为2.47%),土壤酸性磷酸酶活性显著升高(增幅为8.91%),而土壤芳基硫酸酯酶、蔗糖酶和脱氢酶活性的变化差异不显著;生长30d时,土壤脲酶活性仍显著下降(降幅为16.36%),土壤酸性磷酸酶、芳基硫酸酯酶和脱氢酶活性显著升高(增幅分别为35.69%,19.70%和16.83%),而土壤蔗糖酶活性变化差异仍不显著。  相似文献   

13.
The aim of this study was to investigate influence of transgenic and commercial corn hybrids on the behaviour and feeding activity of the pink corn borer (Sesamia cretica Led.). Food consumption was different according to feeding period and hybrids. The feeding ratio of S. cretica on maize hybrids was significantly different between transgenic and commercial hybrids. It appears from the results of this experiment that the antifeeeding activity of transgenic hybrids had greater effect than commercial hybrids one. Thus, it is apparent from these results that transgenic maize was unsuitable because larvae were dead, but the other commercial hybrids were preferable. It can be concluded from the data that the feeding on different maize hybrids had different effects on certain biological aspects of pink corn borer. The impact of untreated Bt. Corn; 0.5% water emulsion of Neem-Azal-T/S and 0.005% water emulsion of Chlorpyrifos insecticides on the behaviour and feeding activity of the pink corn borer S. cretica has been studied. The data showed that larvae stopped feeding from the time when it was fed on untreated Bt. corn or/and non Bt. Corn treated with NeemAzal-T/S 0.5%. The results indicated that Bt. corn, NeemAzal-T/S 0.5% and Chlorphan 48% (0.005%) possessed the toxic effect on pink corn borer S. cretica. According to results, it could be stated that the tested compounds can play an important role in controlling the pink corn borer.  相似文献   

14.
采用氧自由基清除能力(ORAC)方法考察20种多酚类化合物的抗氧化活性。结果表明,该方法具有较优的线性关系(R2=0.997);检测限(LOD)和定量限(LOQ)为0.5~3.1 μmol·L-1,精密度<18%,准确度91%~105%。比较20种多酚类化合物抗氧化活性,对羟基苯甲酸类化合物中,鞣花酸和没食子酸具有较强的抗氧化活性;对羟基肉桂酸类以咖啡酸及其衍生物抗氧化活性最高;在类黄酮组分中,黄烷-3-醇表现出优良的抗氧化特性,黄酮醇次之。ORAC可作为评价多酚类化合物抗氧化的简便、高效的标准化检测方法。  相似文献   

15.
苏云金芽孢杆菌(Bacillius thuringiensis,Bt)制剂是当前应用最广、最有效的生物杀虫剂之一,因其对多种昆虫具有特异性杀虫活性,而被广泛用于农林业和公共卫生等领域的害虫防治,但田间施用后,其速效性差、持效期短和防效不稳定等弊端限制了其进一步的推广。将Bt制剂与增效物质(剂)、因子混合使用以提高其杀虫活性和田间防效稳定性,是最快速、有效的途径之一,因而国内外对此开展了广泛而深入的研究。主要介绍了化学添加剂、化学杀虫剂和生物杀虫剂等添加物对Bt制剂杀虫活性的增效作用研究进展,并探讨了增效物质(剂)、因子的开发和应用前景,以期为开发安全、高效的Bt制剂的增效物质(剂)、因子提供一定的参考。  相似文献   

16.
E G Beale  C S Katzen  D K Granner 《Biochemistry》1981,20(17):4878-4883
N6,O2'-Dibutyryladenosine 3',5'-phosphate (Bt2cAMP) induces the synthesis of the gluconeogenic enzyme, phosphoenolpyruvate carboxykinase (GTP) (EC 4.1.32), in rat liver by increasing the activity of messenger ribonucleic acid (mRNA) coding for this enzyme (mRNAPEPCK) more than 20-fold (from less than 0.01% to greater than 0.20% of total mRNA activity) as determined by using in vitro translation systems which measure only active mRNAPEPCK. The increase in mRNAPEPCK activity could result from increased synthesis, increased processing, or decreased inactivation rates. Actinomycin D and cordycepin inhibit mRNAPEPCK induction by 89% and 70%, respectively, a result that indicates a requirement for ongoing RNA synthesis but that does not distinguish which of these steps is regulated by cAMP. We have employed a kinetic approach, not involving RNA synthesis inhibitors, to determine the half-life of mRNAPEPCK both during a period of deinduction following glucose feeding and during a subsequent induction by Bt2cAMP. An estimated half-life of 20 +/-5 min during both of these periods indicates that Bt2cAMP has no effect on the rate of inactivation of mRNAPEPCK. We conclude that Bt2cAMP effects the increase in activity of mRNAPEPCK by promoting its synthesis or processing.  相似文献   

17.
Screening of different adjuvants, namely, suspending agents, phagostimulants, stickers, antimicrobial agents, and UV screens to develop aqueous biopesticidal suspensions of Bacillus thuringiensis (Bt) variety kurstaki HD-1 fermented broths, specifically, nonhydrolyzed sludge, hydrolyzed sludge, starch industry wastewater, and soya (commercial medium), were investigated. The selected suspending agents [20% (wt:vol)] included sorbitol, sodium monophosphate, and sodium metabisulfite with corresponding suspendibility of 74-92, 69-85, and 71-82%, respectively. Molasses [0.2% (wt:vol)] increased adherence by 84-90% for all fermented broths. The optimal phagostimulants [0.5% (wt:vol)], namely, soya and molasses, caused entomotoxicity increase of 3-13 and 7-13%, respectively. Sorbic and propionic acids showed high antimicrobial action [0.5% (wt:vol)], irrespective of fermentation medium. Sodium lignosulfonate, molasses, and Congo red, when used as UV screens [0.2% (wt:vol)], showed percent corresponding entomotoxicity losses of 3-5, 0.5-5 and 2-16, respectively. The Bt formulations, when exposed to UV radiation, showed higher half-lives (with and without UV screens) than the fermented broths or semisynthetic soya medium and commercial Bt formulation. UV screen-amended nonhydrolyzed, hydrolyzed, and starch industry wastewater formulations showed 1.3-1.5-fold higher half-lives than commercial Bt formulation. Thus, the recommended formulation comprises sorbitol, sodium monophosphate, sodium metabisulfite (suspending agents); molasses, soya flour (phagostimulants); molasses and skimmed milk powder (rainfasteners); sorbic and propionic acids (antimicrobial agents) and sodium lignosulfate; and molasses and Congo red (UV screens). These waste-based Bt formulations offer better UV resistance in comparison with commercial formulation.  相似文献   

18.
The induction of alkaline phosphatase (ALP) by dibutyryl adenosine 3':5'-cyclic monophosphate (Bt2cAMP) was investigated in strain JTC-12 . P3 cells derived from monkey (Maccaca irus) kidney cortex. ALP activity was increased by Bt2cAMP in a dose-dependent manner, reaching a plateau at concentrations higher than 5 mM with the activity being about 4 times that of the controls. The concentration of Bt2cAMP required for half-maximal induction of ALP activity was about 0.8 mM. ALP activity was increased rapidly by Bt2cAMP for the first 5 days and then continued to increase gradually towards a plateau level. Removal of Bt2cAMP from the medium caused a rapid decrease in the activity, suggesting that the induction of ALP activity by Bt2cAMP is reversible. ALP activity was induced synergistically in the presence of 1 mM sodium butyrate together with Bt2cAMP at concentrations from 0.01 to 1 mM. It was also found that in the presence of 1 mM Bt2cAMP, sodium butyrate increased ALP activity in the same manner as Bt2cAMP did in the presence of 1 mM sodium butyrate. Although dexamethasone, a potent glucocorticoid, had no effect on ALP activity in control cells, the hormone suppressed the ALP activity induced by Bt2cAMP in a dose-dependent manner. At concentrations above 0.2 mM, two xanthine derivatives, theophylline and 3-isobutyl-1-methyl-xanthine (IBMX), also inhibited the induction of ALP activity by 1 mM Bt2cAMP. Inhibitors of protein synthesis, cycloheximide (1.5 micrograms/ml) and pactamycin (10 micrograms/ml), as well as inhibitors of RNA synthesis, actinomycin D (2 micrograms/ml) and alpha-amanitin (50 micrograms/ml), suppressed the induction of ALP activity.  相似文献   

19.
以Bt基因来源于中国的棉花品种泗抗1 号(常规种)、泗抗3 号(杂交种)和来源于美国的棉花品种99B(常规棉)、岱杂1 号(杂交棉)为材料,研究了不同高温水平下Bt 棉盛铃期铃壳中Bt 蛋白含量变化及氮代谢生理特征.结果表明: 铃壳中Bt 蛋白含量随温度升高而降低,与对照相比(32 ℃),常规棉品种在38 ℃、杂交棉品种在40 ℃以上时,铃壳中Bt 蛋白含量大幅度下降.其中,常规种泗抗1号和99B在38 ℃时分别下降53.0%和69.5%;杂交种泗抗3号和岱杂1号在40 ℃时下降64.8%和54.1%.铃壳Bt 杀虫蛋白含量下降显著时,其可溶性蛋白含量明显下降,游离氨基酸含量明显提高,GPT活性显著下降,蛋白酶活性显著增加.高温影响铃壳的氮代谢引起Bt蛋白的分解加剧,合成减弱,从而造成Bt蛋白含量减少,抗虫性下降.  相似文献   

20.
Thrombin-induced release of arachidonic acid from human platelet phosphatidylcholine is found to be more than 90% impaired by incubation of platelets with 1 mM dibutyryl cyclic adenosine monophosphate (Bt2 cyclic AMP) or with 0.6 mM 8-(N,N-diethylamino)-octyl-3,4,5-trimethoxybenzoate (TMB-8), an intracellular calcium antagonist. Incorporation of arachidonic acid into platelet phospholipids is not enhanced by Bt2 cyclic AMP. The addition of external Ca2+ to thrombin-treated platelets incubated with Bt2 cyclic AMP or TMB-8 does not counteract the observed inhibition. However, when divalent cation ionophore A23187 is employed as an activating agent, much less inhibition is produced by Bt2 cyclic AMP or TMB-8. The inhibition which does result can be overcome by added Ca2+. Inhibition of arachidonic acid liberation by Bt2 cyclic AMP, but not by TMB-8, can be overcome by high concentrations of A23187. When Mg2+ is substituted for Ca2+, ionophore-induced release of arachidonic acid from phosphatidylcholine of inhibitor-free controls is depressed and inhibition by Bt2 cyclic AMP is slightly enhanced. The phospholipase A2 activity of platelet lysates is increased by the presence of added Ca2+, however, the addition of either A23187 or Bt2 cyclic AMP is without effect on this activity. We suggest that Bt2 cyclic AMP may promote a compartmentalization of Ca2+, thereby inhibiting phospholipase A activity. The compartmentalization may be overcome by ionophore. By contrast, TMB-8 may immobilize platelet Ca2+ stores in situ or restrict access of Ca2+ to phospholipase A in a manner not susceptible to reversal by high concentrations of ionophore.  相似文献   

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