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1.
昆虫几丁质酶及其在害虫防治中的应用   总被引:2,自引:0,他引:2  
李瑶  范晓军 《昆虫知识》2011,48(5):1489-1494
几丁质是昆虫重要的结构性组分,在昆虫生长发育的各个时期都需要一定量的几丁质来维持其代谢平衡.昆虫几丁质酶可以降解昆虫体壁和围食膜中的几丁质,作为一种潜在的生物杀虫剂在害虫防治方面具有广阔的应用前景.随着对昆虫几丁质酶研究的不断深入,目前已克隆到了30余种昆虫几丁质酶,并应用于转基因作物和基因工程微生物中,对害虫具有一定...  相似文献   

2.
种群监测是害虫种群预测与防治决策制定中十分重要的环节,而利用信息化学物质进行昆虫成虫种群监测,与其他各虫态或寄主被害率等的抽样调查方法相比,具有简便、省工、费用低、具种特异性、在低虫口密度下灵敏、监测范围广等特点。信息化学物质的应用主要包括昆虫种类和分布区检测、害虫发生期监测和发生量或为害水平监测。前两个方面的应用没有争议,而害虫发生量监测比较复杂,具有正反两方面的事例,其可靠性存在争议。本文在总结国内外研究结果的基础上,对如何提高利用信息化学物质进行监测和预测的可靠性进行了探讨。影响信息化学物质监测和预测害虫危害程度的因素很多,包括信息化学物质的成分、组成、剂量、释放速率,诱捕器种类和林间设置方法,监测对象的生物学、种群动态和发生阶段,害虫的生活环境条件(包括生物学因素如寄主种类、组成、年龄和密度等以及非生物因素如气候因子等),危害损失的估计方法,以及预测模型的类型和建模方法等。研究分析表明,正确的信息化学物质组成和比例、适当的信息化学物质用量和诱芯载体对信息化学物质的持续稳定释放是监测可靠性的基础,诱捕器的种类、设置方式、密度也需要进行测试并规范化,另外还需根据所监测对象的特性及其所处的环境研究制定特定的种群密度水平或寄主被害率统计方法及预测模型,建立系统的监测规范和程序。只要建立了符合所监测害虫特性和所处环境条件的监测方案,基于信息化学物质的害虫监测是可靠的。  相似文献   

3.
The spotted stem borer, Chilo partellus (Swinhoe, 1885) (Lepidoptera: Crambidae), an invasive pest of wild and cultivated grasses in Asia and Africa, was found for the first time during periodic surveys of maize fields in the East Mediterranean region of Turkey in September and October 2014. The pest was recorded in maize fields of three of four provinces surveyed (Adana, Hatay and Osmaniye; it was not detected in Icel province). The Mediterranean corn stalk borer, Sesamia nonagrioides Lefebvre (Lepidoptera: Noctuidae), is the dominant maize pest in the East Mediterranean region of Turkey, followed by the European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae). The new invasive species comprised 4.9% of the total number of collected lepidopteran pests collected from maize stems and cobs in locations infested by C. partellus. No natural enemies of the new pest were recorded during our surveys. We discuss possible interactions among these three lepidopteran pests sharing the same habitat, prospects for control of C. partellus by the control methods currently used against S. nonagrioides and O. nubilalis, and also speculate on the path of invasion taken by C. partellus into Turkey.  相似文献   

4.
21世纪害虫管理的一些特征展望   总被引:16,自引:0,他引:16  
戈峰  苏建伟 《昆虫知识》2002,39(4):241-246
分析了近年来国内外IPM研究的进展 ,认为未来的害虫管理是以作物的控害作用为中心 ,以农田生态系统或区域性生态系统为对象 ,以大量信息管理为基础 ,以发展新技术 (转基因作物和昆虫性信息素 )和农民参与为重点 ,以生态调控为手段 ,以持续发展为方向。从而使害虫管理提高到一个新的境界  相似文献   

5.
害虫灾害研究的复杂性理论框架   总被引:1,自引:0,他引:1  
害虫灾害是高度复杂的大系统 ,表现出不均匀性、差异性、多样性、突发性、随机性、可预测性和周期性等复杂性特征 ,使得经典的理论和方法已不适用于害虫灾害的研究。依据复杂性科学和分形、神经网络、混沌及小波等非线性科学的发展及其近期在害虫灾害中的部分研究成果 ,该文从复杂大系统出发 ,构建了害虫灾害研究的复杂性理论框架 ,为深入研究害虫灾害的成因、机制与预测提供理论依据。  相似文献   

6.
外来害虫蔗扁蛾的寄主范围   总被引:15,自引:0,他引:15  
综述了我国近年传入的害虫蔗扁蛾的寄主植物范围 :到目前为止 ,蔗扁蛾Opogonasacchari(Bo jer)的寄主植物已达 2 8科 87种 8变种 ;其中国外已报导的为 2 4科 4 6种 4变种 ,中国已查到 1 4科 5 5种 2变种 ,且不断发现新的寄主植物 ,有蔓延到多种行道绿化树木和园林花卉植物上的趋势 ,须引起充分关注。  相似文献   

7.
The development of resistance to insecticides is now widespread among insects. Other methods of pest control are also potentially at risk of encountering resistance. A modelling approach is presented here to evaluate the effects of combining methods of insect pest control on the selection for resistance to the control methods. This analysis is based on partitioning the total mortality acting on a population into its constituent components from all known sources, and these are related to selection for resistance. When two control methods are used in combination, selection for resistance against the two is a linear function if the two don't interact, otherwise it may be sublinear or supralinear. A specific example is presented using a model of the Olive fruit fly (Dacus oleae Gmel.) and employing food-baited and pheromone-baited traps for control. The control methods that appear least likely to encounter resistance are natural enemies and the use of pheromone traps for male annihilation. These should be integrated into a control program where possible to minimize the development of resistance to other control methods being used.  相似文献   

8.
An age-structured population model is used as a vehicle for presenting a method for the analysis of interactions between pairs of insect pest control methods. This analysis is based on partitioning the total mortality acting on a population into its constituent components from all known sources. Pairwise critical mortality curves are then constructed which represent the combined mortality required for eradicating the pest population. Effort curves are then constructed from computing the mortality resulting from a given amount of control effort. The convolution of the critical mortality curves and the effort curves then yields the isoclines formed by the effort required of two control methods in combination to achieve eradication. This analysis allows the prediction of either synergism or interference between the control methods and also helps explain patterns observed in previous modelling of such combinations of pest control methods.  相似文献   

9.
Acanthoscelides obtectus Say is a bruchid species of Neotropical origin, and is specialized on beans of the Phaseolus vulgaris L. group. Since the domestication and diffusion of beans, A. obtectus has become cosmopolitan through human-mediated migrations and is now a major pest in bean granaries. Using phylogeographic methods applied to mitochondrial DNA (mtDNA) and nuclear microsatellite molecular markers, we show that the origin of this species is probably further south than Mesoamerica, as commonly thought. Our results also indicate that A. obtectus and its Mesoamerican sister species Acanthoscelides obvelatus, two morphologically close species differing principally in voltinism, speciated in allopatry: A. obtectus (multivoltine) arising in Andean America and A. obvelatus (univoltine) in Mesoamerica. In contrast to Mesoamerica where beans fruit once yearly, wild beans in Andean America fruit year-round, especially in regions showing little or no seasonality. In such habitats where resources are continuously present, multivoltinism is adaptive. According to existing hypotheses, multivoltinism in A. obtectus is a new adaptation that evolved after bean domestication. Our data suggest the alternative hypothesis that multivoltinism is an older trait, adapted to exploit the year-round fruiting of wild beans in relatively aseasonal habitats, and allowed A. obtectus to become a pest in bean granaries. This trait also permitted this species to disperse through human-mediated migrations associated with diffusion of domesticated beans. We also show that diversity of Old World A. obtectus populations can be quite well explained by a single colonization event about 500 bp. Human-mediated migrations appear not to be rare, as our results indicate a second more recent migration event from Andean America to Mexico.  相似文献   

10.
RNAi在害虫防治中应用的重要进展及存在问题   总被引:2,自引:0,他引:2  
RNAi是目前最有可能应用于害虫绿色防控的新技术。2017年6月,美国环境署(EPA)批准了国际上第一例表达昆虫双链RNA(dsRNA)的抗虫转基因玉米MON87411,掀起了利用RNAi技术进行害虫防治研究新的热潮。但是,目前RNAi在害虫防治中的应用还存在一些问题,例如有效靶标基因筛选和应用策略,鳞翅目昆虫对RNAi的敏感性以及双链RNA在环境中的稳定性等等。本文系统总结了RNA干扰现象发现20年来,该技术在害虫防治领域的研究及应用概况,并对RNAi技术应用的可行性、应用方法、存在问题和目前的一些解决办法进行了比较详细的综述。通过对近期研究结果的综合分析发现,dsRNA进入某些鳞翅目昆虫中肠或血淋巴后,被相关核酸酶降解可能是其RNAi效率较低的首要原因。通过对dsRNA进行脂质体修饰,纳米粒子包埋可以在一定程度上解决dsRNA降解的问题,进而提高RNAi效率。  相似文献   

11.
强休眠玉米种子休眠前后的蛋白差异表达   总被引:1,自引:0,他引:1  
以强休眠玉米自交系08-641为试验材料,分别对处于休眠状态下的新鲜收获种子和经过10 d后熟作用破除休眠的种子进行了蛋白质组学差异表达分析。结果表明,通过双向电泳技术在3次重复试验下休眠状态的08-641鲜种子蛋白2-DE图谱上共检测到约600个蛋白质点,在经过10 d后熟作用破除休眠的08-641种子蛋白2-DE图谱上共检测到约620个蛋白质点,其中下调表达蛋白质点4个,上调表达蛋白质点4个,新增蛋白质点8个,缺失表达蛋白质点7个。经过质谱鉴定的差异表达蛋白质主要涉及球蛋白、胚胎晚期丰富蛋白、豆球蛋白等贮藏物蛋白质;蛋白酶体、山梨醇脱氢酶等参与物质代谢的蛋白质;热激蛋白等参与蛋白质结构、细胞功能调控的蛋白质。推测08-641种子休眠是由于种子内休眠相关蛋白的过量表达或缺失抑制了种子的正常萌发。  相似文献   

12.
Abstract Numerous studies indicate that target gene silencing by RNA interference (RNAi) could lead to insect death. This phenomenon has been considered as a potential strategy for insect pest control, and it is termed RNAi‐mediated crop protection. However, there are many limitations using RNAi‐based technology for pest control, with the effectiveness target gene selection and reliable double‐strand RNA (dsRNA) delivery being two of the major challenges. With respect to target gene selection, at present, the use of homologous genes and genome‐scale high‐throughput screening are the main strategies adopted by researchers. Once the target gene is identified, dsRNA can be delivered by micro‐injection or by feeding as a dietary component. However, micro‐injection, which is the most common method, can only be used in laboratory experiments. Expression of dsRNAs directed against insect genes in transgenic plants and spraying dsRNA reagents have been shown to induce RNAi effects on target insects. Hence, RNAi‐mediated crop protection has been considered as a potential new‐generation technology for pest control, or as a complementary method of existing pest control strategies; however, further development to improve the efficacy of protection and range of species affected is necessary. In this review, we have summarized current research on RNAi‐based technology for pest insect management. Current progress has proven that RNAi technology has the potential to be a tool for designing a new generation of insect control measures. To accelerate its practical application in crop protection, further study on dsRNA uptake mechanisms based on the knowledge of insect physiology and biochemistry is needed.  相似文献   

13.
农田生态系统植物多样性对害虫种群数量的影响   总被引:32,自引:5,他引:32  
着重分析植物多样性影响害虫发生为害及种群数量的生态学机制,综合评述了关于这种机制的两种主要假说,即天敌假说和资源集中假说.同时总结了植物多样性增大和减少对害虫控制的有利和不利因素.研究表明农田生态系统中植物多样性的增大在多数情况下能导致某些害虫种群数量的下降,但是目前很难就不同栖境中所有类型的害虫形成一般性的结论  相似文献   

14.
不同间作枣园害虫的群落结构与动态   总被引:11,自引:0,他引:11  
对5种不同间作枣园的害虫群落结构特征进行了研究,结果表明,在不同的间作枣园中,害虫的科、种与个体数是各不相同的,其多样性、均匀度和Berger-Parker指数也有明显差异(p<0.05)。间作牧草或保留杂草的枣园,害虫的科与种以及多样性和均匀度明显(p<0.05)大于间作小麦、大豆和单作枣园,而个体数和Berger-Parker指数则显著(p<0.05)小于单作枣园。枣园害虫个体数的时序动态随季节交替而有明显(p<0.05)的变化,4~8月份害虫的个体数明显(p<0.05)大于3月份、9~10月份。在枣园间作作物、牧草或者适当保留一定数量的杂草,不仅能够充分有效地利用枣园的空间和自然资源,而且增加了生物的多样性,改善了枣园的生态环境,同时提高了有害生物相互制约的能力和枣园单位面积的纯收入。  相似文献   

15.
Heterogeneity of storage proteins in maize   总被引:1,自引:0,他引:1  
Righetti  P. G.  Gianazza  Elisabetta  Viotti  A.  Soave  C. 《Planta》1977,136(2):115-123
The extensive charge heterogeneity of maize (Zea mays L.) zeins observed in isoelectric focusing (IEF) (about 15 bands with pI's in the pH range 6–9) has been found to be independent of extraction procedures or of endosperm development. Zeins do not stain for glycoproteins and exhibit only one lipoprotein component, with pI 3, representing 3–5% of the total protein.Zeins are very resistant to in vitro deamidation, at both acidic and alkaline pH, at high temperatures, and for rather prolonged times. On the basis of the zein content in acidic and basic amino acids, and of the respective pI's exhibited in IEF (mostly in the pH range 7–8) it has been calculated that at least 90% of the glutamic and aspartic acids (52 residues out of a total of 190) are present as asparagine and glutamine.Amino acid analysis of zein fractions isolated by preparative IEF has demonstrated changes in the composition of 18 amino acid residues. However, since these changes affect only neutral and hydrophobic residues, it is concluded that the observed zein heterogeneity is partly based on in vivo deamidation of glutamine and asparagine and partly to spot mutations in some of the genes responsible for zein synthesis.Abbreviations A absorbance - Bis N,N-methylene bisacrylamide - IEF isoelectric focusing - 2-ME 2-meroaptoethanol - mol wt molecular weight - 62 opaque-2 - PAGE polyacrylamide gel electrophoresis - pI isoelectric point - PAS periodic acid-Schiff stain - SDS sodium dodecyl sulphate - ICA trichloroacetic acid - TEMED N,N,N,N-tetramethyl ethylene diamine - Z1 zein extracted with 55% isopropanol - Z2 zein extracted with 55% isopropanol and 0.6% 2-ME - Z 9.6 zein of mol wt 9600 - Z 13.5 zein of mol wt 13,500 - Z 21 zein of mol wt 21,000 - Z 23 zein of mol wt 23,000  相似文献   

16.
An age-structured population dynamics model is presented that incorporates pheromone-trapping and food-trapping as control methods for an insect pest. The model yields the following results. Low rates of pest survivorship allow lower trapping rates for control. Species with long developmental periods are easier to control than those with shorter developmental periods (other factors being equal) due to lower net survival. The rates of pheromone trapping alone for effective control are usually very high. The combination of pheromone and food trapping allows control with much lower trapping rates than either method alone. Even small amounts of immigration of adult pests into the control area renders pheromone control ineffective, whereas food traps suppress both the immigrants and the resident population. Food- (or odor-) baited traps which attract both males and females are only somewhat more efficient than those which attract females alone. The existence of density-dependent population regulation assists the control program substantially, but this assistance declines as food trapping becomes a more important part of the control program. Larval competition strongly affects the required trapping rates for eradication; species in which all larvae exert strong competition are much easier to control than those in whic the younger larvae contribute little to the total competitive depression.  相似文献   

17.
我国新发现一种重要外来入侵害虫——刺槐叶瘿蚊   总被引:13,自引:0,他引:13  
在我国首次发现了一种新的重要外来入侵害虫——刺槐叶瘿蚊Obolodiplosis robiniae (Haldemann)。该害虫原产北美洲东部,危害刺槐叶片。其危害特征十分明显:一般是3~8头幼虫群集危害,在刺槐叶片背面沿叶缘形成纵向卷曲的虫瘿,隐藏其中取食。在我国河北省秦皇岛市、辽宁省一些地区刺槐树的受害率近100%,严重影响刺槐的健康生长,进而引起次期性害虫的发生和危害,造成刺槐死亡。因此,该害虫对我国大面积栽培的刺槐林的生态、经济以及社会效益的发挥造成重大威胁。必须提高警惕,加强检疫,防止其扩散蔓延,并开展防治研究。  相似文献   

18.
Cicadulina bipunctata was originally distributed in tropical and subtropical regions of the Old World. This leafhopper recently expanded its distribution area to southern parts of temperate Japan. In this study, factors affecting the overwintering ability of C. bipunctata were examined. A series of laboratory experiments revealed that cold acclimation at 15 °C for 7 days enhanced the cold tolerance of C. bipunctata to the same level as an overwintering population, adult females were more tolerant of cold temperature than adult males, and survival of acclimated adult females was highly dependent on temperature from −5 to 5 °C and exposure duration to the temperature. The temperature of crystallization of adult females was approximately −19 °C but temperatures in southern temperate Japan rarely dropped below −10 °C in the winter, indicating that overwintering C. bipunctata adults in temperate Japan are not killed by freezing injury but by indirect chilling injury caused by long-term exposure to moderately low temperatures. An overwintering generation of C. bipunctata had extremely low overwinter survival (<1%) in temperate Japan; however, based on winter temperature ranges, there are additional areas amenable to expansion of C. bipunctata in temperate Japan.  相似文献   

19.
黑龙江大兴安岭地区森林害虫发生面积与气象因子的关系   总被引:3,自引:0,他引:3  
王娟  姬兰柱 《生态学杂志》2007,26(5):673-677
对黑龙江大兴安岭地区6个气象台站的气象资料进行整理和分析,从中筛选出影响虫害发生面积的7个气象因子,并分别对其做相关分析,研究了气象因子对种群数量的影响,模拟虫害发生面积预测方程.结果表明:与虫害发生面积密切相关的因子有年积温(≥10℃)、年降水量和干燥度;虫害发生面积同三者的Pearson相关系数分别为0.701、-0.814和0.937;通过分析极端气候现象对虫害面积的影响,发现春季阴雨和虫害面积存在显著的正相关关系,冬冻和春寒对虫害发生面积并没有直接的影响.  相似文献   

20.
African Acacias are often major contributors to the progressive increase in the woody component of savannas, a phenomenon commonly referred to as bush encroachment. They produce large quantities of seed and may have large soil‐stored seed banks. In Hluhluwe–Umfolozi Park, the number of adult Acacia nilotica trees per hectare far exceed that of A. karroo adults. The relative dominance is reversed in the juvenile stage with A. karroo outnumbering A. nilotica threefold outside closed woodlands. Acacia karroo trees were smaller than A. nilotica trees on average, but produced more seeds for a given basal diameter size class. Acacia karroo showed less bruchid infestation than A. nilotica at all stages of pod development. Unlike A. nilotica, a proportion of A. karroo seeds was able to germinate after bruchid attack. We detected no difference between the two species in the soil‐stored seed bank or in the viability of seeds found in the seed bank.  相似文献   

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