共查询到20条相似文献，搜索用时 250 毫秒
1.
四种Bt制剂对落叶松毛虫的毒力测定 总被引：1，自引：0，他引：1
用Ｈ３ａ３ｂ，Ｈ４ａ４ｃ，Ｈ４ａ４ｂ－２四种Ｂｔ制剂对落叶松毛虫进行了室内毒力测定。其毒力（ＬＣ５０）大小为Ｈ４ａ５ｂ－２〉Ｈ４ａ４ｂ－１〉ｈ３ａ３ｂ〉Ｈ４ａ４ｃ，且落叶松毛虫对Ｈ３ａ３ｂ敏感性差异最小，对Ｈ４ａ４ｂ－２敏感性差异最大。再结合毒力曲线及相关系数筛选出一种对落叶松毛虫毒力较强的制剂Ｌ４ａ４ｂ－１，它对１，２龄幼虫的ＬＣ５０分别为每毫升０．８１亿芽孢和１．０４亿芽孢。 相似文献
2.
两年一代落叶松毛虫的防治是个新课题。为更有效的控制其危害，寻找新的杀虫剂势在必行。合力灵是一种新有机磷杀虫剂。经对落叶松毛虫的毒力测定和室内外的药效测定得出：１．５％和３．０％的合力灵制剂对５龄以下落叶志虫幼虫有良好的防治效果，７２ｈ杀虫死亡率分别为９４．６％和９７．３％。１．５％合力灵对４龄叶松毛虫幼虫的致死中量为３２．３０ｍｇ／ｋｇ。研究表明合力灵在防治两年一代落叶松毛虫幼虫上大有前途，可以在 相似文献
3.
Bt制剂对落叶松毛虫卵期寄生蜂的影响 总被引：1，自引：0，他引：1
就几种国产Ｂｔ制剂对落叶松毛虫卵期寄生蜂的影响进行了试验,结果表明,Ｂｔ菌体本身对落叶松毛虫赤眼蜂、落叶松毛虫黑卵蜂、落叶松毛虫宽缘金小蜂和跳小蜂均无明显影响,可能是由于Ｈ４ａ４ｂ－１和Ｈ５ａ５ｃ制剂中的二甲本对一些卵寄生蜂有明显的影响。 相似文献
4.
落叶松毛虫的质型多角体病毒 总被引：1，自引：0，他引：1
在对落叶松毛虫进行综合治理研究时，从得病幼虫体内分离出一株质型多角体病毒（ＤｓＣＰＶ）。鉴于该病毒在国内未见报道，对其进行了形态、生物测定、组织病理及林间防治试验，结果质型多角体为０．１６μｍ×１．５７μｍ；病毒粒子为１６．０ｎｍ×５８．１ｎｍ；３龄和５龄落叶松毛虫幼虫的ＬＣ５０分别为２．８１×１０４ＰＩＢ／ｍＬ和７．１７×１０４ＰＩＢ／ｍＬ；该病毒感染幼虫中肠７２ｈ后形成多角体，１４４ｈ后形成大量的多角体。用１．１７×１０８ＰＩＢ／ｍＬ浓度的病毒悬液进行林间防治试验，其死亡率达８２％以上，平均达８４．６２％。 相似文献
5.
苏云金杆菌对小地老虎的毒力测定 总被引：2，自引：0，他引：2
采用叶片浸蘸法测定４株苏云金杆菌菌株对小地老虎１龄幼虫的毒性,毒力回归式分别为Ｙ＝１１．６３６１＋２２．３６６５Ｘ、Ｙ＝３．０７４６＋１５．５５７９Ｘ、Ｙ＝８．０４００＋２３．５２９５Ｘ、Ｙ＝７．３４０９＋１８．２９９０Ｘ,Ｂｔ对小地老虎１－３龄幼虫的毒杀效果随幼虫期上升呈显著下降,Ｂｔ处理龄幼虫的死亡率仅在０－５．００％,与对照无显著差异。经初步观察,受测菌株对小地老虎有一定的亚和死效应,表现在 相似文献
6.
肉鸡日粮中添加复合酶制剂的饲养效应 总被引：1，自引：1，他引：1
在商品代ＡＡ肉鸡日粮中添加０．１％复合酶制剂观测对肉鸡生产性能的影响。试验结果表明，１４日龄试验用鸡平均体重３２３ｇ比对照组鸡高３．８５％，差异显著（Ｐ〈０．０５）；料重比；试验组为１．４９，比对照组降低３．３％，４９日龄平均体重，试验组２０８６ｇ比对照组提高５．５５％，差异显著，全期料重比两组无显著差异，说明复合酶制剂对提高肉鸡增重和前期的饲料报酬的明显效果，可取得较好的经济效益。 相似文献
7.
大兴安岭落叶松毛虫生物学特性的研究 总被引：4，自引：0，他引：4
１９９０年黑龙江省大兴安岭林区发生了大面积落叶松毛虫危害，发生面积达１００多万公顷，根据生产防治工作的需要，对大兴安岭落叶松毛虫生物学特性进行了系统研究，搞清高落叶松毛虫在黑龙江在兴安岭林区为２年发生一代，第１年以２－４龄幼虫越冬，第２年以５－７龄幼虫越冬。经室内饲养测定结果幼虫为９龄，并对卵，幼虫，蛹，成虫的生活习性进行了系统的观察和描述，通过生物学特性的研究为该虫的综合防治提供了理论依据。 相似文献
8.
苏云金杆菌菌液与化学农药混用毒杀菜青虫的增效作用 总被引：4，自引：0，他引：4
ｔ菌液与０．０２５％敌百虫剂或０．０２５％乙酰甲胺磷剂以不同比例混用对菜青虫毒杀有不同程度的增效作用。Ｂｔ菌液与０．０２５％敌百虫剂以１∶１，１∶３和３∶１配比混用增效作用明显，杀虫率比Ｂｔ菌液单剂提高３０％。田间试验表明Ｂｔ菌液与敌百虫１∶１混用时防治菜青虫的效果可达８８％。 相似文献
9.
老江河鲤鱼种群动态研究 总被引：1，自引：0，他引：1
应用Ｂｅｖｅｒｔｏｎ－Ｈｏｌｔ模式,对老江河鲤鱼种群动态进行了研究。结果表明：①ｖｏｎ Ｂｅｒｔａｌａｎｆｆｙ生长方程的主要参数Ｌ∞＝９４．８ｃｍ,Ｗ∞＝１７１２６．７ｇ,ｋ＝０．１７２７,ｔ０＝－０．４８８７;②补充年龄ｔｒ为１龄,开捕年龄ｔｃ为２龄,极限年龄Ｔλ为１７龄;③自然死亡系数Ｍ＝０．１５０３,自然死亡率Ｄ＝０．１１１８;捕捞死亡系数Ｆ＝０．４７４４,捕捞死亡率Ｅ＝０．３５２８;总死亡 相似文献
10.
乌江下游森林枯枝落叶水文特性的研究 总被引：9，自引：0，他引：9
通过对乌江下游森林枯枝落叶及不同分解层现存量、持水率、持水量、吸水速度及有效拦蓄水量的测定，结果表明：１．乌江下游阔叶林枯枝落叶现存量平均为１６．２ｔ／ｈｍ￣２，针阔混交林ｌ７．０ｔ／ｈｍ￣２，针叶林９．３ｔ／ｈｍ￣２，灌丛草地５ｔ／ｈｍ￣２。针叶林枯落物分解程度最低，阔叶林分解程度最高。２．各分解层的吸水能力阔叶林＞针阔混交林＞针叶林，分解程度越高，持水能力越强。３．枯枝落叶桉吸水速度快慢可分为三个吸水阶段，速度分别为１５～３．４／ｈ，０．０３～０．５ｇ／ｈ，０．００６～０．０３ｇ／ｈ。其中，未分解层在三个阶段都具有吸水作用。４。乌江下游森林枯落物的有效拦蓄水量为０．５～０．３ｔ／ｈｍ￣２。 相似文献
11.
利用8000IU·滋L-1苏云金杆菌(Bt)悬浮剂对油松毛虫进行了室内生物测定和松林林间防治试验。结果表明,Bt悬浮剂对油松毛虫有很高致死作用。分别利用500,400和300倍稀释液喷雾松枝饲喂2龄幼虫,处理120h后,幼虫死亡率分别为32.50%,35.00%和62.50%。平均症状级别达1.625~2.575,致死作用迅速。林间施用Bt悬浮剂500,400和300倍稀释液,处理7d后,幼虫校正死亡率为74.68%~84.81%,10d后防治效果达85.00%~90.00%,显著高于25%灭幼脲三号悬浮剂的对照处理。 相似文献
12.
[目的]筛选对苏云金芽孢杆菌(Bacillusthuringiensis,简称Bt)可湿性粉剂具有最佳增效作用的物质,并对增效作用显著的混配组合进行了增效作用的评定。[方法]以小菜蛾为生物测定昆虫,采用浸叶法测定了6种添加物对苏云金杆菌(Bacillusthuringiensis,Bt)可湿性粉剂的毒杀增效作用。[结果]研究发现0.1%ZnCl2、0.5%ZnCl2、1.0%ZnCl2、1.0%MgCl2、0.5%硼酸、1.0%硼酸、0.5%柠檬酸和1.0%柠檬酸对Bt可湿性粉剂表现出增效作用,其中0.5%硼酸对Bt可湿性粉剂的增效作用最强,增效比为17.2,1.0%ZnCl2次之,增效比为15.6。同时,杀虫速度的测定结果显示,0.5%硼酸的加入使Bt可湿性粉剂的致死中时缩短了约10h,加快了Bt的杀虫速度。此外,当将1.0%ZnCl2和0.5%硼酸分别与Bt可湿性粉剂溶液室温下混合放置15d后,两种混合物的毒力均没有明显的变化。[结论]硼酸作为Bt可湿性粉剂的增效因子,不但有利于增强Bt制剂的杀虫效果而且还可以提高其杀虫速度,从而在一定程度上克服了Bt制剂杀虫效果差和杀虫速度慢等实际问题。 相似文献
13.
[目的]筛选对苏云金芽胞杆菌(Bacillus thuringiensis,简称Bt)MB-15可湿性粉剂具有最佳增效作用的物质,并对增效作用显著的混配组合进行了增效作用的评定。[方法]以小菜蛾为生物测定昆虫,采用浸叶法测定了6种添加物对苏云金杆菌MB-15可湿性粉剂的毒杀增效作用。[结果]研究发现0.1%ZnCl2、0.5%ZnCl2、1.0%ZnCl2、1.0%MgCl2、0.5%硼酸、1.0%硼酸、0.5%柠檬酸和1.0%柠檬酸对Bt MB-15可湿性粉剂表现出增效作用,其中0.5%硼酸对Bt MB-15可湿性粉剂的增效作用最强,增效比为17.2,1.0%ZnCl2次之,增效比为15.6。同时,杀虫速度的测定结果显示,0.5%硼酸的加入使Bt MB-15可湿性粉剂的致死中时缩短了约10 h,加快了Bt的杀虫速度。此外,当将1.0%ZnCl2和0.5%硼酸分别与Bt MB-15可湿性粉剂溶液室温下混合放置15 d后,两种混合物的毒力均没有明显的变化。[结论]硼酸作为Bt MB-15可湿性粉剂的增效因子,不但有利于增强Bt制剂的杀虫效果而且还可以提高其杀虫速度,从而在一定程度上克服了Bt制剂杀虫效果差和杀虫速度慢等实际问题。 相似文献
14.
The susceptibility of the Asian corn borer, Ostrinia furnacalis to Bacillus thuringiensis (Bt) formulation and Bt corn was evaluated using insect bioassays for 6 years. Four strains of O. furnacalis were developed by laboratory selection from the laboratory strain reared on a non-agar semi-artificial diet. The RR-1 strain was exposed to a commercial formulation of B. thuringiensis subsp. kurstaki (Btk) incorporated into the artificial diet, the RR-2 strain was exposed to Bt corn (MON810)tissue incorporated into the diet, and the SS-1 and SS-2 strains were reared on the standard diet with or without non-Bt corn tissues material. Decreasing susceptibility of O. furnacalis to Bt and to Bt corn were found in each selected strain although the ED50 and larval weight fluctuated from generation to generation. The resistance of Bt-exposed strain (RR-1)to Btk increased 48-fold by generation 39; the Bt corn-exposed strain (RR-2) increased its resistance 37-fold to Btk by generation 24. No larvae of SS-1 survived when they were exposed to the leaves of Bt corn, Bt1 1 and MON810. However,2-54% of the RR-1 (generation 46) and RR-2 (generation 20) larvae survived a 3 day-exposure to the leaves of Bt1 1 and MON810. The survival of both selected strains on Bt corn silk increased by 10-69%, and the larval weights after many generations selection were increased by 15-22% compared with the unselected susceptible strain. The young larvae were much more susceptible to Bt than older larvae. The highest mortality occurred when the larvae were exposed to Bt at the neonate stage. All of the results suggested that ACB could not only develop resistance to Bt preparation but also to Bt corn. Bt had significant effects on the growth and development of Asian corn borer than on the larval mortality. In order to maintain the long-term effectiveness of Bt pesticide and Bt corn, the resistance management should pay much attention to the larvae that may have opportunities to grow and developed on non-Bt corn or alternate hosts before they attack the Bt corn plants and the survival of larvae after Bt application. 相似文献
15.
水稻二化螟初孵幼虫对锐劲特较敏感（b值〉2,LC50约为0.04～0.06mg/kg）,对Bt的敏感性则较差（b在1.4～2.0;LC50约为5～8mg/kg）,通过一系列的室内实验筛选出Bt和锐劲特不同组合对二化螟联合毒力效应在1：1至1：3的配比范围内具有较强的增效作用,且随着Bt所占份额的提高,共毒系数值有增加的趋势。结合田间药效和经济效益,选用Bt：锐劲特=1：1的配方,经田间小区实验结果表明：2%锐劲特·Bt制剂田间用量60g/667㎡、75g/667㎡、90g/667㎡处理22d后的防效分别为：60.34%、67.73%、71.32%,高于对照药剂16000单位Bt50g/667㎡处理样。对复配药剂进行毒性测定表明：2%锐劲特·Bt制剂属低毒类农药。 相似文献
16.
Effect of three insect-resistant maizes expressing Cry1Ie,Cry1Ab/Cry2Aj and Cry1Ab on the growth and development of armyworm Mythimna separata(Walker) 
下载免费PDF全文
下载免费PDF全文 Three transgenic maize events(IE09 S034, Shuangkang 12–5 and C0030.3.5) produced Cry1 Ie, Cry1 Ab/Cry2 Aj and G10-EPSPS, Cry1 Ab and EPSPS, respectively, all of which target the Asian corn borer. The oriental armyworm Mythimna separata(Walker) is the secondary target. In this study, the effects of the three Bt maizes on the development and survival of armyworm were studied. The results showed that IE09 S034 had insecticidal activity against 1 st instar larvae, and the survival rate of armyworm fed with Bt maize for 10 days was 46.2%, significantly lower than that of the control. The larvae at 3 rd–6 th instar were more tolerant of the Bt toxin than the early instar larvae. However, Shuangkang 12-5 had good insecticidal activity against 1 st–5 th instar larvae. The mortality was nearly 100% when the larvae were fed with Shuangkang 12-5 before 3 rd instar, and the toxin had quick-acting efficacy. This event significantly inhibited the development of armyworm; that is, the larval duration of the 3 rd and 4 th instar larvae fed with Shuangkang 12-5 was prolonged by 4.5 and 3.0 days, respectively. The pupal weight and egg number were also significantly lower than those of the control. For C0030.3.5, it could control 1 st–5 th instar larvae effectively. The mortality rates were all over 50% if 1 st–3 rd larvae were fed with this event. The pupal weight of 4 th–6 th instar larvae fed with Bt maize were only 53.9, 56.8 and 54.6%, respectively, compared to that of the control. The number of eggs laid was significantly less than the control. The results indicate that all three transgenic maize events exhibit the potential to provide effective control of early instar larvae of armyworm, which can be commercialized in future to control lepidoptera pests such as Asian corn borer and armyworm. 相似文献
17.
Bt制剂对小菜蛾及其主要寄生蜂的选择毒性 总被引：3，自引：0，他引：3
测定了6种Bt制剂对小菜蛾幼虫的毒力及其寄生蜂菜蛾绒茧蜂和菜蛾啮小蜂成虫的选择毒性。6种Bt制剂对小菜蛾3龄幼虫的毒力差异显著,毒力大小顺序为：绿茵〉高效Bt／杀虫单〉Bt可湿性粉剂〉苏泰〉农泰〉比力Bt（8010）浓缩型粉剂。Bt制剂对小菜蛾主要寄生蜂的选择毒性研究结果如下,绿茵和苏泰对菜蛾绒茧蜂成虫属于有害类药剂,比力、高效Bt／杀虫单和农泰属于中度有害类杀虫剂,Bt可湿性粉剂属于无害类药剂;绿茵、高效Bt／杀虫单对菜蛾啮小蜂成虫属于有害类药剂,具有很强的杀伤力,比力和苏泰属于中度有害类杀虫剂,Bt可湿性粉剂和农泰属于无害类药剂。 相似文献
18.
Bt L-93菌株培养基的正交试验及培养代谢 总被引：2，自引：0，他引：2
采用正交试验方法对ＢｔＬ－９３菌株发酵培养基进行筛选,确定了最佳配方ＳＦ－１号,其发酵液菌数可稳定达到７０亿／ｍＬ。通过对２～３龄落叶松毛虫进行生物测定,杀虫效果可达８０％以上。同时考查了此菌株在发酵培养基上的生长、ｐＨ变化、溶氧以及还原糖和氨基氮等诸因子和代谢情况。 相似文献
19.
肥料增效剂对玉米干物质积累及氮养分吸收的影响 总被引：3，自引：0，他引：3
【目的】研究肥料增效剂与化肥配施对玉米干物质积累及氮养分吸收的影响,为玉米生产节本增产提供理论参考。【方法】采用盆栽试验,每1kg土中N、P、K肥施用量分别为：0．368、0．235和0．350g,设常规施肥处理（T1）,另设5个增施处理（T2-T6）,按在常规施肥处理基础上分别增施2mL不同肥料增效剂（F1-F5）,收获期测定玉米籽粒、苞叶、秸秆、根系等全N、P、K养分含量及玉米的养分吸收量和养分利用率。【结果】与常规施肥T1处理相比,增施增效剂处理玉米鲜苞重增加12．0～17．50g／盆,增重4．3％～6．2％,玉米籽粒重增加3．9％～6．9％;施用肥料增效剂处理的植株干物质积累量与常规施肥相比增幅为4．97％～6．65％。玉米植株各器官（秸秆、籽粒、苞叶＋穗轴和根）氮养分吸收量均显示施用增效剂处理优于对照,增幅为：秸秆20．60％～37．00％;籽粒7．20％～13．15％;苞叶＋穗轴12．43％～30．94％;根3．13％～37．75％。施用肥料增效剂处理与单施用化肥处理相比,氮肥利用率提高5．0％～7．2％。【结论】在常规施肥的基础上增施肥料增效剂能显著增加玉米植株干物质量及提高,氮肥利用率。 相似文献
20.
Xiang ZHANG Ming-yuan ZHOU Ya-bing LI Zhen-yu LIU Yuan CHEN De-hua CHEN 《农业科学学报》2021,20(5):1229-1238
Cotton bolls exhibit the lowest insecticidal efficacy among all organs of Bt cotton, which would ultimately affect the yield formation. The objective of this study was to investigate the effects of different urea concentrations on the seed Bt protein contents, seed cotton yield and the corresponding protein metabolism mechanism. The experiments were conducted during 2017–2018 cotton growing seasons. Two cultivars, Sikang 3(hybrid, SK3) and Sikang 1(conventional, SK1), were treated with six urea concentrations and their seed Bt protein contents were compared during boll formation period. The urea spray concentration had a significant effect on the seed Bt toxin content and seed cotton yield. Spraying of either 5 or 6% urea led to higher insecticidal protein contents and higher seed cotton yield for both cultivars. Moreover, the highest amino acid and soluble protein contents, as well as GPT and GOT activities, and lower protease and peptidase activities were observed at the 5 to 6% urea levels. Significant positive correlations between the seed Bt toxin and amino acid contents, and between the seed Bt toxin content and GPT activities were detected. The lower boll worm number and hazard boll rate were also observed with the 5 to 6% urea treatments, which may be the reason why nitrogen spraying increased the seed cotton yield. Therefore, our results suggested that the seed Bt toxin content and insect resistance were impacted markedly by external nitrogen application, and 5 to 6% urea had the greatest effect on insect resistance. 相似文献