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为明确水稻害虫稻水象甲Lissorhoptrus oryzophilus Kuschel的取食习性,系统调查了稻水象甲在贵州省中部地区的取食植物种类,并测定了越冬成虫取食起始温度,分析了取食斑大小和取食斑数量与根部幼虫数量之间的关系。结果表明,稻水象甲成虫可取食66种植物,其中禾本科48种、莎草科13种、黑三棱科1种、美人蕉科1种、百合科2种、天南星科1种;根据稻水象甲的取食和生活习性,将这些植物划分为寄主植物、喜食植物和可取食植物,分别有4种、51种和11种。在全黑暗和全光照的条件下,稻水象甲越冬成虫取食虫数均随温度升高而逐渐升高,其50%越冬成虫开始取食的温度分别是15.3℃和11.9℃。不同地点的稻水象甲越冬成虫的单个取食斑长度、宽度和面积均无显著差异。线性回归分析结果表明,取食斑数量与取食斑长度之间以及取食斑长度与取食面积之间呈显著正相关,而取食斑数量与根部幼虫数量无显著相关性。 相似文献
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转基因抗虫植物对天敌昆虫的影响 总被引：18，自引：0，他引：18
迄今对16种捕食性和7种寄生性天敌昆虫个体进行的毒性测定表明，转基因植物对天敌昆虫没有直接毒性；取食了转基因植物的猎物对大部分捕食性天敌昆虫个体无毒副作用。取食了转基因植物的寄主害虫如表现亚致死反应，则对寄生蜂个体无毒副作用，甚至对寄生蜂与抗虫作物间有增效作用；如寄主表现致死反应，则对寄生蜂个体有明显毒副作用。转Bt基因棉花，玉米和马铃薯田中主要广谱捕食性天敌种群数量等于或显著高于常规田，生测中对普通草蛉的副作用并未使其大田种群受到不良的影响；寄生性天敌昆虫种群数量除在个别Bt棉田中明显减少外，在其他Bt作物田中均等于或高于常见田，除个别棉田外，未发现Bt作物田中天敌群落受到不良影响，部分研究发现Bt作物田中某些非靶标刺吸口器害虫上升为主要害虫，数量明显高于常规田，建议采用“三层次检测体系”评价转基因作物对天敌昆虫的影响。 相似文献
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为探究地红蝽Pyrrhocoris tibialis St?l的特殊取食行为及其取食选择性，通过在室内外观测并全程记录地红蝽的取食行为，研究其对12种植物种子以及不同部位和不同成熟度苘麻种子的取食偏好性。结果表明，地红蝽室外取食行为包括寻水、吸水、清理、离开、搜寻、摩擦、刺探、插入、携带、攀爬、取食、静止和离开共13个过程；在室内有92%的地红蝽具先吸水后取食的行为，8%只进行吸水行为。地红蝽对苘麻种子的取食偏好性最高，选择率为41.71%，取食时长为77.30 min，刺探次数为3.44次，均显著高于其余植物种子；地红蝽对苘麻种子种皮厚度最薄（96.12μm）的左肩部位取食选择率最高，为28.93%，显著高于其他部位；对成熟度最高的深色苘麻种子取食偏好性最高，选择率为42.00%，取食时长为182.94 min，刺探次数为6.44次，高于次深色和浅色苘麻种子。表明地红蝽取食行为是吸水-携带种子攀爬-取食的特殊取食行为，且偏好取食苘麻种子并对种皮厚度最薄部位和成熟度最高苘麻种子的取食偏好性强。 相似文献
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许多粉虱寄生蜂雌蜂对粉虱若虫的攻击方式不仅是寄生,而且还能取食。本文以海氏桨角蚜小蜂Eretmocerus hayati作为测试寄生蜂,Q隐种烟粉虱和温室白粉虱作为寄主,在非选择和双向选择条件下调查了寄生蜂对寄主的取食和寄生选择性。研究结果表明,非选择试验条件下,海氏桨角蚜小蜂48 h内取食1～4龄烟粉虱和温室白粉虱若虫的数量分别为10.7、6.4、6.7、5.0头和4.4、3.7、2.8、2.3头,寄生1～4龄烟粉虱若虫的数量分别为22.1、27.5、25.4、16.5头,但不能寄生各龄期温室白粉虱若虫;而在选择试验条件下,寄生蜂取食1～4龄烟粉虱若虫的数量分别为同龄期温室白粉虱若虫数量的1.8、2.6、2.5、1.5倍。说明寄生蜂的取食寄主能力明显受寄主种类和龄期的影响。海氏桨角蚜小蜂更适合用来防治烟粉虱,但不适于防治温室白粉虱。 相似文献
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通过布局合适的蜜源植物,以提高农田生态系统的害虫防控服务,已成为一种常用的生境管理技术。然而,如何筛选理想的蜜源植物是保护生物防治中迫切需要解决的现实问题。本研究通过室内试验构建蜜源植物对寄生蜂寄生能力影响的数据库,分析了不同蜜源植物的效应值与寄生蜂和蜜源植物关键生态特征的相关性。结果表明,花序类型是筛选蜜源植物的最重要特征,其中复伞形花序植物的花对寄生蜂寄生能力的促进作用最显著,而花单生、头状花序和穗状花序植物的对寄生蜂寄生能力的促进作用不明显。赤眼蜂等微小型寄生蜂的生殖潜力的高低对其取食蜜源植物后的寄生能力影响不显著。寄生蜂的寄主类型、种群类型等不会影响蜜源植物对赤眼蜂的寄生能力。 相似文献
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取食对寄生蜂的影响 总被引：1，自引：0，他引：1
寄生蜂是调节昆虫种群动态的重要因子之一,其对寄主害虫产生影响的因素主要有寄生蜂摄入的营养、寄生蜂的寿命和生殖力以及其对寄主的搜寻效率等。寄生蜂的营养主要来源于幼蜂体内营养积累和成蜂取食两个途径。其中成蜂取食又包括取食寄主和取食非寄主食物两个方面。某些种类的成蜂通过取食寄主来获得生存和生殖所需的营养,但是大部分成蜂需要取食糖类来作为其主要能源,而且糖类对寄生蜂的生存和生殖也会产生一定的影响。本文综述了寄生蜂的食物来源、食物营养在寄生蜂体内的分配、取食寄主和非寄主食物对寄生蜂的影响以及寄生蜂在寄主搜寻和非寄主食物搜寻之间的权衡,以期为寄生蜂的饲养和利用提供参考。 相似文献
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为明确自然调控短梳角野螟Meroctena tullalis(Walker)的优势寄生蜂—螟蛉绒茧蜂Cotesia ruficrus(Haliday)的室内饲养技术,开展生物防治,在室温条件下采用单头饲养的方法,研究了补充外源营养对螟蛉绒茧蜂寿命和繁殖力的影响。结果表明,补充不同外源营养均能延长螟蛉绒茧蜂的寿命,延长时间依次为蜂蜜水蔗糖葡糖糖果糖清水不饲喂;取食蜂蜜水、蔗糖、葡萄糖、果糖和清水后,雌蜂总产卵量分别为125.7、101.2、94.3、76.1和28.9粒;补充不同浓度的蜂蜜水对成蜂寿命的影响依次为15%10%20%5%;在取食频率次数大于2 d供饲1次时,随着供饲次数的增加可显著延长寄生蜂寿命,以1 d供饲1次效果最佳。该寄生蜂的日取食节律分别在08:00—10:00和16:00—17:00出现取食高峰,且种内性别存在时差错位现象。 相似文献
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在饲养伪钝绥螨的10种植物花粉中,核桃、洋槐、贴梗海棠、仙人球、迎春和卷心菜等可使其取食并完成发育,前4种还可使其产卵。花粉粒的外部形态结构,是影响该螨能否取食的重要因素之一。用桃、苹果花粉饲养伪钝绥螨,对其F_1代生活力有明显的不良影响。取食桃花粉的F_1代,幼螨间相互残杀,并取食未孵化的卵,使成活率降低。取食苹果花粉的F_1代可正常完成发育,但成螨性比降低,产卵时自食其卵。试验表明,单纯喂食桃或苹果花粉难以进行伪钝绥螨的累代饲养。 相似文献
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福寿螺配偶个体大小选择性初步观察 总被引：7，自引：0，他引：7
通过野外观察与实验研究,掌握了福寿螺的婚配体制及其配偶选择性规律。福寿螺与多数低等动物一样,其婚配属于乱交制,无固定配偶;雌螺对与其交配的雄螺个体大小没有选择性,而雄螺对雌螺的个体大小有选择性,倾向于与较大个的雌螺交配。 相似文献
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F.M. Ashton O.T. de Villiers R.K. Glenn W.B. Duke 《Pesticide biochemistry and physiology》1977,7(2):122-141
Time- and concentration-course studies were conducted to determine the effect of thirteen herbicides on photosynthesis, respiration, RNA synthesis, protein synthesis, and lipid synthesis using isolated single leaf cells. Each herbicide was from a different chemical class. Appropriate 14C-substrates and product purification procedures were used for each process prior to liquid scintillation counting. The most sensitive metabolic site of inhibition was photosynthesis for atrazine, bromacil, dichlobenil, monuron, and paraquat; RNA synthesis for dalapon and dinoseb; protein synthesis for chlorpropham; and lipid synthesis for CDAA, chloramben, 2,4-D, EPTC, and trifluralin. However, with several herbicides, one or more process was almost as sensitive as the one mentioned above. All herbicides inhibited more than one process, and the most sensitive site of inhibition may not be the same process that was inhibited the greatest at the maximum concentration and maximum exposure time used. Therefore, a concept of metabolic sites of action, rather than a primary site of action, appears to be more meaningful for herbicides. 相似文献
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为了研究青稞种子外部和内部携带真菌情况,比较不同杀菌剂对青稞种子的带菌消毒效果和对幼苗生长的影响,为青稞种子播前包衣处理和种传真菌病害防控提供依据,采用离体平皿法对云南迪庆‘云青1号’、‘云青2号’和‘短白青稞’3个主栽品种进行带菌检测,并对种子进行拌种或浸种处理测定6种杀菌剂对种子消毒效果,分析杀菌剂对种子发芽和幼苗生长的影响。结果表明:供试青稞种子表面携带的优势菌群为青霉(Penicilliumspp.)、镰刀菌(Fusariumspp.);种子内部寄藏的真菌主要为镰刀菌、核腔菌(Pyrenophoraspp.)、附球菌(Epicoccumspp.)、丝核菌(Rhizoctoniaspp.)、链格孢(Alternariaspp.)和木霉(Trichoderma spp.)。青稞不同品种的种子表面及内部携带的真菌种类差异较大。致病性测定表明,镰刀菌对种子萌发和幼苗生长影响最大,后期出现幼苗坏死现象。45%咪鲜胺EW、75%百菌清WP、50%福美双WP对青稞种子携带真菌均有显著抑制作用和消毒效果,50%福美双WP消毒效果最优,达100%;45%咪鲜胺EW、75%百菌清WP、50%福美双WP处理对青稞种子发芽和幼苗生长均无显著影响。 相似文献
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Effects of timing and method of application of Penicillium oxalicum on efficacy and duration of control of Fusarium wilt of tomato 总被引：3，自引：0，他引：3
The effects of timing and method of application of Penicillium oxalicum on the control of fusarium wilt of tomato were investigated. Application of P. oxalicum to tomato seedlings in seedbeds reduced disease caused by Fusarium oxysporum f.sp. lycopersici in a growth chamber by 45–49% and in glasshouse experiments by 22–69%. Disease suppression was maintained for 60–100 days after inoculation with the pathogen in the glasshouse. No disease reduction was observed in tomato plants where P. oxalicum was applied to seeds. Treatment with P. oxalicum did not affect the population of F. oxysporum f.sp. lycopersici in the rhizosphere. 相似文献
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E. LIMPERT B. C. CLIFFORD A. DREISEITL R. JOHNSON K. MÜLLER A. ROELFS C. WELLINGS 《EPPO Bulletin》1994,24(1):109-112
A variety of systems of designation has evolved to name pathotypes of plant pathogens. The systems were evaluated to determine those best suited for particular purposes. Virulence and avirulence/virulence formulae of pathotypes have advantage over the use of consecutive numbers or letters given in chronological order of pathotype discovery. As soon as pathotype information exceeds a certain level of complexity, mathematical codes are most advantageous, in particular two codes, octal notation and coded triplets. A more universal adoption of the most appropriate codes is recommended to ease communication and comparisons of results. 相似文献
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Christopher D. Keating Lindy M. Holden-Dye Robert J. Walker 《Pest management science》1996,46(3):263-266
The neuropeptide AF2 has a complex set of actions on the dorsal muscle strip of Ascaris suum, including a potentiation of the acetylcholine-stimulated muscle contraction. Caffeine at 100 μm and 5 mm inhibited this potentiation, as did 100 μm theophylline in two out of six studies. The cyclic-AMP-potentiating compounds IBMX, dibutyryl cAMP and forskolin had no effect on the AF2-induced potentiation of the acetylcholine-stimulated muscle contraction. These preliminary data suggest that the potentiating action of AF2 is not mediated by a cAMP pathway. 相似文献
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Magdalina I. Luzhnova Lyudmila M. Shekhtman 《Pesticide biochemistry and physiology》1975,5(3):205-210
The effect of meturine on the light processes of photosynthesis was studied.Meturine is a herbicide for weed control in potato and cotton crops. It is a N-phenyl—N-hydroxy—N′-methylurea.The experiments were carried out on isolated pea and spinach chloroplasts.When examining photosystem I, reduced DPIP was used as an electron donor, whereas methyl-viologen served as an electron acceptor. When examining photosystem II, DPIP represented the electron acceptor.The obtained experimental results have pointed to the absence of the effect of meturine upon the photoreaction I.Unlike N-phenyl—N′, N′-dimethylureas (CMU, DCMU) meturine has been a very weak inhibitor of photoreaction II.The authors explain the photoreaction II inhibition of chloroplasts from plants treated with herbicidal doses of meturine by conversion of N-phenyl—N-hydroxy—N′-methylurea into Hill reaction inhibitor(s). N-Phenyl—N′-methylurea can be one of such meturine metabolites.Meturine herbicidal action is accounted for by meturine transformation into Hill reaction inhibitor(s) in the plant tissues. 相似文献
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The mode of action of the 2,4-diphenyl-1,3-oxazoline acaricide/insecticide etoxazole has been argued to be moulting inhibition, but experimental results supporting this hypothesis are lacking. This study investigated the effect of etoxazole on chitin biosynthesis in the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). Etoxazole induced moulting defects in fall armyworm larvae similar, if not identical, to those caused by benzoylphenylureas, a well-known class of insecticidal chitin biosynthesis inhibitors. Furthermore, in contrast to untreated larvae, the chitin content in the integuments of larvae several days after treatment did not differ from that in freshly ecdysed individuals, thus suggesting strong chitin biosynthesis inhibition in vivo. A more detailed investigation of the inhibitory potential by incubating cultured integument pieces from larvae of S. frugiperda with [14C]N-acetyl-D-glucosamine, a radiolabelled chitin precursor, revealed I50 values of 2.95 and 0.071 microM for etoxazole and triflumuron respectively. The incorporation of radiolabel into potassium hydroxide-resistant material was inhibited by etoxazole in a dose-dependent manner. Based on these results, it is concluded that the acaricidal and insecticidal mode of action of etoxazole is chitin biosynthesis inhibition. 相似文献