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1.
We used a published biological model and published economic algorithm to evaluate western corn rootworm (Diabrotica virgifera virgifera) IPM for growers over a 15 year period beginning after significant adoption of insecticidal corn (Zea mays). The primary focus of our analysis was the economic evaluation (grower profit) of transgenic insecticidal corn expressing Cry34/35Ab1 as event 59122 and its refuge planted continuously year after year (continuous corn). We chose the reference scenario for economic comparison to be the use of soil insecticides on continuous, conventional corn. The model simulated the evolution of rootworm resistance to transgenic insecticidal (Bt) corn; but did not simulate resistance to soil insecticides. We evaluated refuge sizes of 5–50% for single-trait Bt corn and 5–20% for pyramided Bt corn with two traits targeting western corn rootworm. We considered the role of block and blended (seed mixture) refuges for insect resistance management (IRM). Results demonstrated that, for pyramided Bt corn, block refuges planted in the same location within a field year after year gave the greatest overall profit for grower. If growers relocated their block refuge annually (which is the most common practice), then a 5% blended refuge gave the greatest return. For single-trait Bt corn, 10–20% blended refuges gave greater economic return compared to block refuges ranging from 5% to 50%. Single-trait Bt corn with 5–20% block refuge (with no insecticide) was superior to soil insecticide use alone in all cornfields.  相似文献   

2.

Background  

There is an urgent need to explore and utilize naturally occurring products for combating harmful agricultural and public health pests. Secondary metabolites in the leaves of the Tree of Heaven, Ailanthus altissima L. have been reported to be herbicidal and insecticidal. The mode of action, however, of the active compounds in A. altissima are not understood. In this paper, we report the chemical characteristics of the herbicidal and insecticidal components in this tree, and will discuss the effect of light on the bioactivity of the active components.  相似文献   

3.
假蒟中胡椒碱的分离鉴定及杀虫活性研究   总被引:1,自引:0,他引:1  
为进一步探讨假蒟的杀虫活性成分,采用生物活性示踪法从假蒟乙醇提取物中分离纯化出1种活性成分,其化学结构经MS、1H NMR、13C NMR分析鉴定为胡椒碱。以螺旋粉虱为供试对象,采用叶片浸渍法测试胡椒碱及假蒟乙醇提取物对螺旋粉虱成虫和若虫的毒杀活性及杀卵作用,结果表明:胡椒碱及乙醇提取物对螺旋粉虱成虫和若虫均具有很好的杀虫活性,对成虫LC50值分别为28.59、224.31 mg/L,对若虫的LC50值分别为65.91、336.68 mg/L,胡椒碱对成虫的毒力优于若虫,与对照药剂印楝素无显著性差异;其杀虫活性明显高于假蒟乙醇提取物;胡椒碱及乙醇提取物有一定的杀卵作用,但作用方式有所不同,胡椒碱对初孵幼虫有较高的致死率,而假蒟乙醇提取物则明显影响螺旋粉虱卵的孵化。  相似文献   

4.
黄蝉属(Allamanda L.)植物是重要的观赏植物。综述了黄蝉属植物种质资源及其系统学、生理生态特性、药理作用、杀虫活性和栽培繁殖等方面的研究现状,归纳总结该属植物在园林中的配置应用情况,并对该属植物今后的研究方向进行展望。  相似文献   

5.
The control and elimination of German cockroach, the most important worldwide pest species, has been an economic and public health success. Too many studies have been conducted in Iran, whereas these researches was scattered in form of national and international articles that has needed to add up of them in an overview article. With doing of this work the way is smooth to future studies and the strategies of these studies will be distinguished. This article is outlook in direction of above aims. The susceptibility level and insecticide resistance mechanisms of German cockroach to organochlorated, organophosphate, carbamate and pyrethroid insecticide groups have been studied. The new insecticidal compounds include fipronil and avermectins acting at GABA and glutamate receptors in proximity to chloride channels, diacylhydrazines mimicking the action of ecdysone, indoxacarb acting at a novel site in sodium channels and imidacloprid, thiamethoxam and spinosad acting at novel sites on the nicotinic acetylcholine receptor, several promising products acting at new target sites, which are currently not affected by resistance that will be used for pest control specially Blattella germanica. Attentive to resistance of B. germanica to current consuming insecticides and ever-increasing add to intensity of it, the researchers have been considering the susceptibility level of B. germanica and efficiency estimation of them to above-mentioned insecticides for control of this pest. The strategies of future researches are study of the susceptibility level of B. germanica and efficiency estimation of them to above-mentioned insecticides for control of this pest in Iran.  相似文献   

6.
为进一步探讨软枝黄蝉杀虫活性成分,以菜青虫为靶标昆虫,采用生物活性示踪法分离鉴定软枝黄蝉杀虫活性成分,采用小叶碟添加法测定活性成分对菜青虫幼虫的杀虫活性;3种活性成分鉴定分别为黄蝉花定、黄蝉花辛和黄蝉花素。活性测试结果表明,3种活性成分对菜青虫5龄幼虫均有很强的拒食作用,处理后48 h AFC50值分别为0.071,0.045和0.103 mg/mL,同时,3种化合物对菜青虫还有较强的毒杀作用,其中,以黄蝉花素毒杀作用最强,其LC50值仅为0.026 mg/mL,优于对照药剂川楝素(0.033 mg/mL);环烯醚萜类化合物可能是软枝黄蝉主要的杀虫活性成分。  相似文献   

7.
Hybanthus parviflorus is a perennial shrub, widely distributed in the tropical and subtropical regions of America, and is known as ‘violetilla’ in Argentina. Previous phytochemical studies of this species led us to the isolation and determination of the primary structure of a novel macrocyclic polypeptide, the cyclotide hypa A. Here the insecticidal activities of extracts of H. parviflorus were determined against Ceratitis capitata Wied., the Mediterranean fruit fly or ‘Medfly’. Mortality in the different life stages of Medfly, total mortality and modifications of the insect’s physiology caused by 50% EtOH and CH2Cl2 extracts of H. parviflorus were evaluated. In addition, we determined the occurrence of ursolic acid, β-sitosterol and the polyphenols quercetin, quercetin-3-methyl ether, apigenin, luteolin, kaempferol, rutin, caffeic acid and chlorogenic acid. The promising insecticidal activity of 50% EtOH extracts of H. parviflorus and its purified fractions was related to the presence of cyclotides. The insecticidal activity of CH2Cl2 extracts could be related to the presence of polyphenols, ursolic acid and β-sitosterol.  相似文献   

8.
近年研究发现,一些虫生真菌在自然界中具有双重寄主,不仅可以寄生在昆虫中,还可以定殖在植株中。虫生真菌在植物中定殖,既能促进植物生长,又能提高寄主植物抗性,这种独特的生态学功能,有助于更好地在植物保护中发挥作用。本文综述内生性虫生真菌在植物中的定殖特性及这种定殖特性对害虫和植物病原体的间接控制效果,探讨虫生真菌植物内生性及其提高寄主植株对病虫害抗性的作用机理,提出虫生真菌作为双重生防治剂的可能性和未来的研究方向。  相似文献   

9.

Background  

Glucosinolate breakdown products are volatile, therefore good candidates for insect fumigants. However, although they are insecticidal, the mode of action of such natural products is not clear. We studied the insecticidal effect of these compounds as fumigants, and monitored the production of carbon dioxide by the insects as a probe to the understanding of their mode of action.  相似文献   

10.
Bt基因抗虫玉米是目前商品化进程最快的转基因作物之一,并被广泛应用于农业生产,其抗虫性和经济效益已得到普遍肯定,但外源基因的导入一定程度上改变了玉米自身的基因序列,因此转Bt基因抗虫玉米对生态安全的影响也备受关注。本文从转Bt基因抗虫玉米发展现状及对非靶标昆虫影响的角度对转Bt基因玉米的安全性研究加以综述。  相似文献   

11.
花生种质资源的综合评价   总被引:16,自引:4,他引:12  
对5700份花生种质资源的植物学性状和经济性状、抗病性和种子品质性状进行了鉴定评价,筛选出高抗锈病种质92份,高抗早斑病种质77份,高抗晚斑病种质53份,高抗根结线虫资源3份,高抗青枯病资源102份,抗锈病兼抗早斑病资源58份,抗锈病兼抗晚斑病资源49份,抗锈病兼抗早、晚斑病资源45份,抗青枯病兼抗根结线虫资源2份,抗青枯病兼抗锈病资源1份。蛋白质含量达34%以上的33份,含油量达58%以上的24份,油酸含量达67%以上的18份,亚油酸含量达47%以上的15份。不同类型不同来源的花生品种的植物学性状、经济性状、抗病性和种子品质性状均有显著差异。  相似文献   

12.
Bacillus thuringiensis (Bt) transgenic cotton has been planting in large-scale for more than 10 years in China. It was observed that resistance to bollworm was reduced with the application of big-boll cultivars in China. The objective of the study was to investigate the effects of boll size on the contents of CryIA insecticidal protein in boll shell and cotton seed during the course of boll development. Two experiments were conducted at the Yangzhou University Farm, Yangzhou, China. In 2004, three cultivars including Sikang 1 (small-boll), Xiangza 3 (medium-boll) and Kemian 3 (big-boll) were compared for boll shell volume and 100-seed weight from 10 to 40 days after flowering (DAF), and insecticidal protein contents in boll shell and cotton seed from 10 to 50 DAF. As expected, the differences between cultivars were significant for all the four characteristics. Cultivars with bigger boll shell volume had higher 100-seed weight but lower insecticidal protein contents in both of the boll shell and cotton seed. The correlation between boll size and boll insecticidal protein content was negative (−0.653). The correlation between 100-seed weight and cotton seed insecticidal protein content was significantly negative (−0.645). In 2005, leaf cut (LC) and square removal (SR) treatments were applied to Sikang 1 and Sikang 3. The boll shell volume and 100-seed weight were decreased by LR, but increased by SR. LC significantly enhanced and SR significantly reduced the insecticidal protein contents of boll shell and cotton seed. The correlation between boll size and boll insecticidal protein content (−0.870) and the correlation between 100-seed weight and cotton seed insecticidal protein content were both highly significant and negative (−0.841). Therefore, the results of the study indicated that the boll insecticidal protein content was significantly affected by boll size. The implications of the observed results in breeding, cultural practices and pest management were discussed.  相似文献   

13.
为筛选出适宜徽县烟区生态条件的烤烟新品种,在徽县烟区以秦烟96为对照,对2个烤烟品种云烟99、云烟100的生物学性状、抗病性、经济性状、外观质量进行了观察分析。试验结果表明,云烟99经济性状表现最好,产值(51829.93元/hm^2)和均价(22.83元/kg)最高;株型为腰鼓型,主脉稍粗,大田生长势强、整齐一致,分层落黄好,性状稳定,易烘烤,原烟外观质量好;较对照的发病率和病情指数低,抗病性较强。初步确定云烟99适宜在徽县烟区推广种植。  相似文献   

14.
栽培大豆种质资源对大豆菌核病的抗性评价   总被引:1,自引:0,他引:1  
采用离体叶柄接种法鉴定了200份栽培大豆高世代品系对大豆菌核病菌株Jia30和Jian29的抗感反应.结果表明:在所有的参鉴材料中没有发现免疫类型,但各品系间抗性有一定的差异.供试200个品系中既表现抗Jia30菌株义表现抗Jian29菌株的材料占供试材料的2%;抗Jia30菌株的材料占3%;抗Jian29菌株的材料占5%,根据抗性资源筛选结果,这些抗性材料可合理地用于大豆生产,并为大豆抗病育种亲本选择和利用品种布局进行大豆菌核病生态控制提供了依据.  相似文献   

15.
为增加"鱼-稻"共生的综合经济与生态效益,探索水稻种植与生产的新途径,选育并通过浙江审定了首个鱼塘种稻专用新品种安粳优1号。该品种具有株型高大、茎秆粗壮、节间发达水生根、抗倒性强等特点。本文介绍了安粳优1号的选育过程、特征特性和高效栽培技术。  相似文献   

16.
生态环境与种植密度对河南省夏玉米产量的影响   总被引:2,自引:0,他引:2  
以郑单958、郑单528、伟科702和中单909为材料,在河南省北部、东部和南部3个生态区的6个试验点进行玉米产量及适宜密度范围差异研究。结果表明,生态环境对玉米产量及适宜密度的影响大于品种类型。4个玉米品种的产量为伟科702中单909郑单528郑单958,其中,中单909的地点间变异系数最小,产量稳定性较好。4个品种玉米产量在3个生态区的6个试验点间的差异都达到了显著水平,总体表现为豫北豫南豫东。4个品种在豫北试验点的适宜密度差异较大;在豫东和豫南试验点的适宜密度差异较小。3个生态区的6个试验点的土壤速效磷和速效钾、生育期光照和降水量不同是产量及适宜密度差异的主要原因。  相似文献   

17.
"全能杀虫平台"具有高效、安全、经济节能等优点,将"全能杀虫平台"与生产上广泛应用的"稻鸭共育"模式相结合,建立了"优质稻-全能杀虫平台-鸭"有机稻栽培模式,可有效提高有机稻的病虫害防治效果。本文主要介绍了该模式的病虫害防治效果以及关键栽培技术。  相似文献   

18.
转Bt毒蛋白基因玉米及其抗虫性研究进展   总被引:4,自引:3,他引:4  
杨春英  宋建成 《玉米科学》2001,9(1):088-093
本文从转Bt毒蛋白基因玉米的培育及商品化,Bt毒蛋白基因在转基因玉米中的遗传分离与整合、对玉米螟及其它害虫的杀虫效果、对天敌种群数量和玉米病害发生程度的影响、玉米螟对转Bt毒蛋白基因玉米产生抗性及解决措施、应用转Bt毒蛋白基因玉米潜在的生态风险性等方面对国内外最新研究进展进行了综述。  相似文献   

19.
本研究对国外引进的6个长果黄麻优良品种进行2年5点生态适应性试验与抗病性、品质鉴定。结果表明:引进品种比我国对照增产的有4个,占引进长果种品种的66.66%,其中3个达到极显著水平;O-1丰产性最好,增产19.19%,经济性状优良;稳定性与适应性较好的品种为O-4;纤维高于500支的特优异品种1个为O-6。引进的黄麻品种在抗病能力上与我国品种基本相当,具有高抗黄麻小黑点炭疽病能力的品种有O-2和O-4,没有发现免疫材料。  相似文献   

20.
草坪草对干旱胁迫的反应概述   总被引:4,自引:0,他引:4  
干旱胁迫是影响草坪草生长最主要的环境胁迫因子之一。在干旱胁迫下,草坪草的根、茎、叶均会表现出一定的生态适应性,还会发生叶片蒸腾和光合作用减弱、渗透调节物质累积、活性氧代谢失调等生理生化反应,而且在细胞水平和基因水平上也会发生变化,这都与草坪草的抗旱调节机制有着密切的联系。目前我国关于草坪草的抗旱性研究还处于起步阶段,基因工程技术的研究和应用是今后的主要发展方向。  相似文献   

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