Effect of dihydrodillapiole on pyrethroid resistance associated esterase inhibition in an Indian population of Spodoptera litura (Fabricius)

Resistance in Spodoptera litura (Fabricius) has been attributed to enhanced detoxification of insecticides by increased levels of esterases, oxidases and/or glutathione S-transferases. Enzyme inhibiting insecticide synergists can be employed to counter increased levels of such enzymes in S. litura. Dihydrodillapiole induced synergism of pyrethroid toxicity was examined in the laboratory-reared third instar larval population of S. litura collected in Delhi (susceptible), and Guntur (resistant) region of Andhra Pradesh, India. The Guntur population was found to be 7.04 and 10.19 times resistant to cypermethrin and lambdacyhalothrin, respectively. The activity of cypermethrin, lambdacyhalothrin and profenophos against susceptible and resistance populations of S. litura, was gradually increased when used along with a plant-derived insecticide synergist dihydrodillapiole. The α-naphthyl acetate hydrolysable esterase activity in Delhi population was less as compared to the Guntur population. Resistance associated esterases in Delhi population were inhibited by pre-treatment with dihydrodillapiole. The esterase level in insect was instantly reduced initially, sustained for about 3 h and equilibrated at 4 h post treatment. The esterase activity of Guntur population was increased to 1.28 μmoles/mg/min at 2 h post treatment and subsequently reduced to lower than 0.70 μmoles at 4-12 h post treatment. The variation in esterase activity is suggestive of its homeostatic regulation in test populations. Dihydrodillapiole thus caused significant reduction of resistance in S. litura to cypermethrin, lambda cyhalothrin and profenophos.     

Variation of acephate susceptibility and correlation with esterase and glutathione S-transferase activities in field populations of the tarnished plant bug, Lygus lineolaris

The tarnished plant bug (TPB) has increasingly become an economically important pest of cotton. Heavy dependence on insecticides, particularly organophosphates and pyrethroids, for TPB control facilitated resistance development to multiple classes of insecticides. To better understand resistance and explore ways to monitor resistance in field populations, this study examined acephate susceptibility and the activities of two major detoxification enzymes in nine field populations collected in the Delta region of Mississippi and Arkansas in 2010. Two Arkansas populations from Reed and Backgate had 3.5- and 4.3-fold resistance to acephate, as compared to a susceptible laboratory strain. Extensive planting of cotton and heavy chemical sprays is a major driving force for resistance development to acephate in Mid-south cotton growing areas. Reduced susceptibility to acephate was highly correlated with elevated esterase activities. The acephate-resistant populations from Backgate, Lula, and Reed consistently had higher (up to 5.3-fold) esterase activities than susceptible populations. Regression analysis of LC₅₀s with kinetic esterase activities revealed a significant polynomial quadratic relationship with R² up to 0.89. Glutathione S-transferase (GST) also had elevated activity in most populations, but the variations of GST activities were not significantly correlated with changes of acephate susceptibility. Finally, examination of esterase and GST inhibitors indicated that suppression rates (up to 70%) by two esterase inhibitors in 2010 were slightly lower than those detected in 2006, and ethacrynic acid (EA) inhibited GST effectively in both years. Two other GST inhibitors (sulfobromophthalein and diethyl maleate) displayed significantly lower suppression rates in 2010 than those detected in 2006, suggesting a potential genetic shift in pest populations and a necessity of continued monitoring for insecticide resistance with both bioassay and biochemical approaches. Results indicated that using major detoxification enzyme activities for resistance monitoring may provide insight into acephate resistance in field populations of TPB.     

Cd~(2+)处理下超氧阴离子与花生萌发的关系

[目的]阐明Cd2+对花生(Arachis hypogaea L.)种子萌发的作用以及花生萌发过程中超氧阴离子(O2-.)含量的变化与酯酶同工酶、淀粉同工酶的关系。[方法]分别采用组织化学定位和电泳技术。[结果]10、30μmol/L Cd2+处理对花生胚根和下胚轴有显著的促进生长作用,使花生子叶中酯酶同工酶和淀粉同工酶活性增强,子叶以及胚根O2-.含量提高。[结论]酯酶同工酶和淀粉同工酶活性的提高与Cd2+诱导的超氧阴离子的提高相关。     

宝巾(Bougainvillea spp.)种质资源同工酶的遗传多样性分析

[目的]分析深圳本地12种宝巾种质资源的遗传多样性。[方法]利用聚丙烯酰胺凝胶电泳法研究宝巾种质资源过氧化物同工酶(POD)和酯酶同工酶(EST)的遗传多样性,并对统计结果进行聚类分析。[结果]各宝巾种质资源间有丰富的遗传多样性,在相似系数为0.63水平上可以聚为2大类。[结论]同工酶的特征谱带应用于品种鉴定是可行的,在一定程度上明确了各宝巾品种的亲缘关系。     

北马兜铃营养生长期过氧化物酶同工酶分析

用聚丙烯酰胺垂直板凝胶电泳技术对北马兜铃营养生长期根、幼茎、老茎、叶柄、未展开幼叶、展开幼叶和成熟叶的过氧化物酶(POD)同工酶进行了分析。结果表明:北马兜铃营养生长期7个组织器官共有10条POD酶带,其POD同工酶具有组织特异性,其中未展开幼叶的POD同工酶酶带丰富、活性较强、含量较高,是POD同工酶分析最好的材料,而成熟叶片由于POD酶种类太少,最不适合作POD同工酶分析。     

黄芩过氧化物酶同工酶几种酶液提取方法的比较

利用聚丙烯酰胺凝胶电泳对黄芩(Scutellaria baicalensis Georgi)萌发的种子,愈伤组织,悬浮细胞及幼苗过氧化物酶几种酶液提取方法进行比较.结果表明:各种酶液提取方法对不同部位的同工酶提取效果不同.同工酶是研究植物多样性的有力工具,过氧化物酶则是广泛存在于植物体内的一种重要的同工酶,能反映植物生长发育特点、体内代谢状况及对外界环境的适应.     

少果悬铃木遗传分析初步

通过对合肥等地选育出的一球悬铃木少果植株和正常结果植株的体细胞染色体组型分析和过氧化物酶同工酶酶谱分析,找出了两者遗传上的差异。     

中国赖草[Leymus chinensis（Trin）Tzval]与普通小麦（T. aestivum L.）杂交及其后代小 - 赖麦（Triticum - Leymus）的研究

中国赖草（Leymus chinensis）为中国特有,用它与普通小麦（T. aestivum）杂交并经连续选育已获得小 - 赖麦（Triticum-Leymus）新种质7个品系,主要特点是高蛋白质、高赖氨酸含量和抗条锈、叶锈及白粉病。细胞学研究结果：F#-2时在1个完整细胞内只有1,2,3,4,6……等少数染色体,还有大环、长链、桥、落后染色体等异常现象。1987年观察了大量花粉母细胞（13892个）及根尖细胞（435个）染色体,从中筛选出7个品系,其2n=43 - 49者占75.63%,其中n = 22Ⅱ和2n = 49各占90%以上者各有2个品系。叶片酯酶同工酶分析结果表明杂种品系具有双亲互补酶带。     

西瓜F_1代杂交种及其亲本种子幼苗体酶的遗传分析

侧重分析了安徽省杂交西瓜在制种和生产上面积较大６个组合如新澄、新红宝、郑杂五号、金钟冠龙、皖杂一号和聚宝一号及其亲本种子幼苗体内的酯酶和过氧化物同工酶的组成情况和遗传特性。结果表明：１）６个组合中,除金钟冠龙外,其他５个组合的父本间和母本间酯酶酶谱表现相似;但每个组合父、母本间均存在差异。２）６个组合的Ｆ１代杂交种酯酶酶谱表现为母本不完全显性。３）除郑杂五号外,其他５个组合的Ｆ１代杂交种过氧化物酶谱和其父、母本间表现相似。另讨论了用酯酶同工酶筛选亲本组配杂交种和预测杂种优势的可行性。     

黄颡鱼雌、雄个体血清蛋白、酯酶同工酶及血红蛋白的电泳分析

采用聚丙烯酰胺梯度凝胶垂直板(PAGE)电泳,对黄颡鱼雌、雄个体血清蛋白、酯酶同工酶(EST同工酶)及血红蛋白(Hb)进行了分析。结果表明：黄颡鱼雌、雄个体的血清蛋白存在明显差异,表现在B1区雄性个体比雌性个体多1条MI带,B2区雌性个体比雄性个体多1条MA带,少2条MⅡ带,B3区雄性个体比雌性个体多1条MA带。另外在B2区雌、雄个体间MA带和MI带排列次序也有差异。血清EST雌、雄个体也有明显的差异,雄性黄颡鱼血清EST的酶谱出现了3条酶带无中强带,而雌性黄颡鱼EST的酶谱出现了7条酶带,有4条中强带。雌、雄个体胁只能分离出1条谱带,并且雌、雄之间基本没有差异。