在不同pH条件下铜绿微囊藻藻毒素对棉铃虫幼虫中肠类胰蛋白酶的抑制作用     

李晓军  韩文珍  郝赤 《山西农业大学学报(自然科学版)》2010,30(2):133-136

为探求铜绿微囊藻藻毒素(microcystin)对昆虫产生胃毒影响的机理,选用棉铃虫作为研究对象,在pH=10.4和pH=5.6等不同的酸碱环境条件下,研究了铜绿微囊藻藻毒素粗提物对棉铃虫幼虫中肠类胰蛋白酶的水解专性底物活性的抑制影响。结果显示微囊体藻藻毒素粗提物在碱性环境下对棉铃虫幼虫的类胰蛋白酶具有非常稳定的抑制作用,并与铜绿微囊藻毒素的浓度增加表现出显著的相关性。在pH=8.6的弱碱性条件下的抑制效率要高于在pH=10.4的强碱性条件下的抑制效率,证明铜绿微囊藻是一种很有潜力的生物杀虫物质,具备了应用于农业害虫防治的潜力。  相似文献   

一种基于Matlab的棉铃虫飞行视频的处理方法研究     

王晟博  陈钟荣  高月波  安晶晶 《现代农业科技》2010,(21):177-179,182

为了给昆虫行为学的研究者提供可靠的统计资料,提出了一种从视频流中提取运动目标物的坐标值的方法,并设计实现了该算法。视频文件经过预处理后,提取静止背景,再确定每张图像中试验昆虫的区域,随后选取恰当的阈值,经过维纳滤波和中值滤波,从中提取运动目标物的特征。最后算出运动目标物在图像中的坐标值。通过对提取效果和统计结果进行分析,证明该方法有较高的提取率和可靠性,是实现视频资料数据化的有效手段。  相似文献   

虱螨脲亚致死剂量对棉铃虫生长发育和繁殖力的影响   总被引：1，自引：0，他引：1  

姚永生  熊仁次  韩旭  周永锋 《西北农业学报》2009,18(4):66-69

用虱螨脲亚致死剂量处理棉铃虫1龄幼虫和3龄幼虫,结果表明:虱螨脲具有较强后效性,能降低棉铃虫化蛹率、羽化率、产卵量,提高畸形蛹、畸形蛾比例.1龄幼虫按0.1和0.2 mg/kg一次饲毒后,化蛹率分别为20.00%和15.50%,与对照相比显著降低;处理代雌、雄成虫羽化率分别下降6.50%、9.91%和18.48%、21.76%,雌、雄畸形蛾率分别上升15.61%、12.71%和27.55%、19.50%,产卵量下降34.06%和36.50%.第2、3代与第1代相比,化蛹率、羽化率、产卵量、卵孵化率逐渐有所提高,畸形蛹率、畸形蛾率降低,但与对照仍存在差异,表明虱螨脲对试虫的影响随世代延续而减弱,但至少可持续到第3代,且随用药剂量提高,其影响加大.与1龄幼虫饲毒结果相比,对3龄幼虫的影响程度相对较小,但趋势一致.  相似文献   

红彩真猎蝽对烟草重要害虫捕食选择性研究     

苏湘宁  邓海滨  蔡青年  张茂新 《中国农学通报》2016,32(26):43-47

为更合理、有效地应用红彩真猎蝽防治重要的烟草害虫提供科学依据,采用“Y”型嗅觉仪,研究了红彩真猎蝽成虫对烟蚜若虫、烟青虫和斜纹夜蛾幼虫的选择性及选择偏好。结果表明,红彩真猎蝽成虫对烟蚜若蚜、3龄烟青虫和斜纹夜蛾具有显著的正向趋性,选择3种猎物的红彩真猎蝽数量分别达到34.44%、40.00%、51.11%。从猎蝽选择猎物所需时间来看,红彩真猎蝽选择烟蚜若蚜、烟青虫3龄幼虫、斜纹夜蛾3龄幼虫平均耗时分别为14.53、13.44、9.38 min,且猎蝽选择斜纹夜蛾3龄幼虫的所需时间显著短于选择烟青虫3龄幼虫和烟蚜若蚜。红彩真猎蝽对3种猎物偏好性的研究发现,选择斜纹夜蛾3龄幼虫的红彩真猎蝽成虫数量显著高于选择烟蚜若蚜和烟青虫3龄幼虫的猎蝽(P<0.05),而选择烟蚜若蚜和烟青虫3龄幼虫的猎蝽数量之间没有显著差异(P>0.05)。因此,红彩真猎蝽对斜纹夜蛾3龄幼虫具有显著的偏好性。这些研究结果对人工繁育红彩真猎蝽,并广泛用于防治这些重要害虫,保证农产品安全生产具有重要的意义。  相似文献   

棉铃虫抗性品系与敏感品系的生育特征研究     

于金凤  王金信  刘峰 《山东农业大学学报(自然科学版)》1999,30(4):413-416

在人工气候室内,对棉铃虫夏津抗性品系（ＸＪ－Ｒ）和喀什敏感品系（ＫＳＨ－Ｓ）的生长发育、存活及繁殖特征进行了详细的观察与比较,并构建了两品系的实验种群生命表。结果表明：ＸＪ－Ｒ品系较ＫＳＨ－Ｓ品系在生长发育、存活及繁殖方面不存在不利性,ＸＪ－Ｒ品系相对于ＫＳＨ－Ｓ品系具有１．１０的适合度。  相似文献   

Hemocyte diversity of the American bollwormHelicoverpa armigera     

Govind T. Gujar  Vinay K. Kalia 《Phytoparasitica》2005,33(1):17-27

The hemocytes of the American bollwormHelicoverpa armigera (Hübner) were studied in the last instar larvae by phase contrast microscopy to investigate the differences among 14 populations, collected from ten locations, spread over a distance of approximately 3000 km in six different states of India. The cluster analysis of differential hemocytes showed as many as 11 clusters of populations at 5% and six clusters at 10% homogeneity level. The cluster analysis of hemocytes of seven populations from cotton crops showed five and three clusters at 5% and 10% homogeneity levels, respectively. Diversity of hemocytes of four populations from chickpea was wider than that from cotton. The differences in hemocytes of various populations may be due to space, time, host plant, insecticide use, other agroecological conditions, and insect genetic variabilityper se. The field populations ofH. armigera heavily treated with insecticides appeared to contain more spherulocytes at the expense of plasmatocytes and granulocytes. The treatment of 6-day-old larvae ofH. armigera with cypermethrin decreased plasmatocytes and granulocytes, and increased prohemocytes and spherulocytes in the hemolymph of last instar larvae. Thus, differential hemocyte counts may serve as an indicator of insecticide exposure and the diversity of insect populations. http://www.phytoparasitica.org posting Dec. 20, 2004.  相似文献   

不同品系赤眼蜂对烟青虫卵的寄生选择性   总被引：3，自引：0，他引：3  

王福莲  侯茂林  万方浩  张帆 《中国生物防治》2005,21(3):136-141

采用棚室笼罩试验，研究了松毛虫赤眼蜂和螟黄赤眼蜂的不同品系对不同卵龄烟青虫卵的寄生选择性、松毛虫赤眼蜂HJS品系对烟草不同叶位、叶面上的烟青虫卵及不同植物（辣椒和烟草）上的烟青虫卵的寄生选择性。结果表明，松毛虫赤眼蜂HJS、YYS品系和螟黄赤眼蜂JDM品系对0～12h烟青虫卵的寄生率显著高于12～36h的卵；而螟黄赤眼蜂GGM品系对该二卵龄烟青虫卵的寄生选择性无显著差异。不论位于叶正面、叶背面还是整叶上的卵，松毛虫赤眼蜂HJS品系均对倒10～12叶位的卵寄生选择系数最高，其次为倒13～15叶，对倒1～6叶均较低，这与烟青虫产卵对叶位的选择不同；HJS对所有叶位叶正面烟青虫卵的寄生选择系数均高于对背面的，并以倒1～3和倒4～6叶位最为明显，且HJS对叶正面卵的寄生倾向和程度与烟青虫雌蛾在该叶位正面产卵的倾向及程度存在差异，该差异因叶位不同而不等。HJS对辣椒上烟青虫卵的寄生选择系数较高，而烟青虫偏好产卵于烟草。  相似文献   

Binding of three Cry1A toxins in resistant and susceptible strains of cotton bollworm (Helicoverpa armigera)     

Shudong Luo  Guirong Wang  Kong Ming Wu  Lianyang Bai  Yuyuan Guo 《Pesticide biochemistry and physiology》2006,85(2):104-109

Evolution of resistance by pests is the greatest threat to the continuous success of theBacillus thuringiensis (Bt) toxins used in conventional sprays or in transgenic plants. The most common mechanism of insect resistance to Bt is reduced binding of toxins to target sites in the brush border membrane of the larval mid-gut. In this paper, binding experiments were performed with three ¹²⁵I-Cry1A toxins and the brush border membrane vesicles from Cry1Ac resistant or susceptible strains of Helicoverpa armigera. The homologous competition test showed that there was no significant difference in Cry1Ac-binding affinity, but the concentration of Cry1Ac-binding sites dramatically decreased in the resistant strain (R_t decreased from 5.87 ± 1.40 to 2.23 ± 0.80). The heterologous competition test showed that there were three Cry1Ac-binding sites in the susceptible strain. Among them, site 1 bound with all three Cry1A toxins, site 2 bound with both Cry1Ab and Cry1Ac, and site 3 only bound with Cry1Ac. In the Cry1Ac resistant strain, the binding capability of site 1 with Cry1Ab decreased and site 2 did not bind with Cry1Ac. It is suggested that the absence of one binding site is responsible for H. armigera resistance to Cry1Ac. This result also showed that the resistance fitted the “mode 1” pattern of Bt resistance described previously.  相似文献   

转Bt基因棉与常规棉的棉铃虫发生特点   总被引：1，自引：0，他引：1  

王惠哲  赵立  王永  魏国树  魏长栓 《天津农业科学》2005,11(2):9-11

比较研究了转Bt基因棉保铃棉、中棉30与棉常规品种防治和不防治情况下棉铃虫的发生特点。结果表明:(1)各处理间棉铃虫卵的发生时期基本一致,发生量则差异较大;(2)转Bt基因棉棉铃虫幼虫的发生量远低于常规棉(平均低72.4%);(3)在生长前期各处理均有一定数量的天敌类群,对棉铃虫的发生具有较好的控制作用。  相似文献   

螟黄赤眼蜂对辐照的棉铃虫卵和幅照棉铃虫产的卵寄生的初步研究   总被引：2，自引：0，他引：2  

王恩东  路大光  刘晓辉  李咏军  张书勇  刘琼茹  王华嵩 《核农学报》2002,16(1):36-39

螟黄赤眼蜂对 2 50Gy直接辐照的新鲜棉铃虫卵和未辐照的新鲜棉铃虫卵的寄生率没有显著差异 ;与辐照的新鲜卵相比较 ,辐照的低温保存过的卵的寄生率要低。螟黄赤眼蜂在 2 50Gy辐照棉铃虫所产卵的寄生率取决于卵的受精率  相似文献