五种储粮害虫11个品系的磷化氢抗性测定

本文运用FAO(1975)推荐的测定储粮害虫磷化氢抗性的方法，对米象、谷蠹、赤拟谷盗、平米象和锯谷盗五种储粮害虫的11个品系进行毒力测定，得出它们的LC50值，米象的LS2和GDSo，玉米象HNZZSz—l和GDGZSz—l，谷蠢的QQRd和Rd一7，赤拟谷盗的QQTc-4、SDQHTc—l和HNSQTc—l以及锯谷盗VOs48和HNNYOs—1等11个品系的磷化氢致死中浓度(LC50)分别为0．0088和1．3006，0．0057和0．0058，0．0042和1．3779，0．0047、2．1009和0．9926以及0．0073和0．00090mg/L。其中磷化氢敏感品系为LS2、QQRd、QQTc—4、HNZZSz—l、GDGZSz—l、VOs48和HNNYOs—1；抗性品系为GDSo、RD-7、SDQHTc-l和HNSQTc—l，抗性系数Rf分别为148、327、449和212倍，抗性非常严重。测定结果为今后的磷化氢抗性研究工作提供了基础数据。     

肉桂醛对赤拟谷盗的熏蒸作用及对成虫保护酶活性的影响

为明确肉桂醛对赤拟谷盗Tribolium castaneum各发育阶段的杀虫活性及对成虫几种保护酶活性的影响, 本试验采用三角瓶密闭熏蒸法测定了肉桂醛对赤拟谷盗低龄幼虫、高龄幼虫、蛹和成虫的熏蒸作用及24 h致死中浓度熏蒸后成虫体内超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性。结果表明, 肉桂醛的熏蒸效果与其浓度和赤拟谷盗发育阶段有关, 肉桂醛2.5 μL/L熏蒸72 h对赤拟谷盗成虫的熏蒸效果最好, 幼虫次之。在24 h致死中浓度处理下, 赤拟谷盗成虫体内SOD、POD、CAT活性分别在48、12 h和36 h达到最高, 其活性分别为对照的2.70、1.03倍和1.96倍。随着熏蒸时间的延长, 成虫POD活性在处理36 h后低于对照, SOD、CAT活性分别在处理36~60 h和24~48 h显著高于对照。综上所述, 经肉桂醛熏蒸处理后, 赤拟谷盗成虫体内动态平衡受到破坏, 进而产生毒害作用。因此, 肉桂醛对赤拟谷盗的生物防治有较高的应用价值。     

蛇床子素对三种储粮害虫的触杀毒力测定

采用药膜法对玉米象、米象、赤拟谷盗三种储粮害虫进行了蛇床子素室内毒力测定.96 h的毒力测定结果表明,蛇床子素对玉米象、米象、赤拟谷盗的IC50分别为0.155mg/cm2、0.645mg/cm2、0.656mg/cm2,蛇床子素对储粮害虫具有触杀作用,不同虫种对蛇床子素敏感性不同.     

褐拟谷盗的快速分子鉴定方法

文中应用PCR法和PCR-RFLP法建立了褐拟谷盗的快速分子鉴定方法.结果表明：①PCR法中,采用依据褐拟谷盗COI基因设计的特异性引物进行PCR扩增,其产物经电泳检测证实,能快速准确地鉴定褐拟谷盗;②PCR-RFLP法利用2组简并引物对目标拟谷盗的COI基因进行PCR扩增,并借助HindⅢ限制性内切酶对扩增产物进行酶切后,进行电泳检测,该法也可用于检疫工作中对褐拟谷盗的快速鉴定.     

甲酸乙酯对面粉中赤拟谷盗的熏蒸效果

本文研究了甲酸乙酯对面粉中赤拟谷盗不同虫态的熏蒸作用。通过对熏蒸期间熏蒸剂浓度检测,计算浓度时间乘积(CT)计算不同时间下甲酸乙酯对赤拟谷盗各虫态达到99%控制的处理指标(Lct_(99))。结果表明甲酸乙酯熏蒸能有效防治面粉中的赤拟谷盗各虫态,赤拟谷盗不同虫态对甲酸乙酯的敏感性由强到弱依次为:卵>低龄幼虫>成虫>高龄幼虫>蛹。在23℃条件下处理6h和12h对面粉中赤拟谷盗的Lct_(99)分别为448.42和599.34mg·h/L     

阿维菌素和毒死蜱对玉米象和赤拟谷盗的毒力测定

用3种低毒农药对生活在稻谷中的玉米象和赤拟谷盗2种储粮害虫用喷雾法进行室内毒力测定。结果表明:(1)1.8%阿维菌素乳油(EC)、2%阿维菌素微囊悬浮剂、48%毒死蜱乳油(EC)对玉米象的致死中剂量(LD50)分别为0.01mg/kg、0.07mg/kg、4.65mg/kg,而对赤拟谷盗的LD50分别为0.08mg/kg、0.50mg/kg、5.89mg/kg;(2)在相同剂量下,3种药剂中以1.8%阿维菌素EC对2种害虫的毒杀速度最快;(3)玉米象比赤拟谷盗对这3种药剂更敏感。建议采用1.8%阿维菌素EC、2%阿维菌素微囊悬浮剂、48%毒死蜱EC防治玉米象的使用剂量分别为0.05mg/kg、0.80mg/kg和2.0mg/kg,而防治赤拟谷盗则分别为0.05mg/kg、0.80mg/kg和8.0mg/kg。     

黄色花蝽对杂拟谷盗的模拟控制研究

在整粒小麦及半碎小麦中,黄色花蝽对杂拟谷盗的控制效果较好,但在小麦粉中无控制作用。在半碎小麦中,益害比1:20时,控制效果可达97.65％;在整粒小麦中,采用益害比1:1、1:2、1:4、1:8所得到的控制效果均无显著差异,但随着容器增大控制效果逐渐降低。     

Toxic and repellent effects of Baccharis salicifolia essential oil on Tribolium castaneum

Allelochemical effects were observed when Tribolium castaneum (Herbst) adults were treated with Baccharis salicifolia (Ruiz & Pavon) Pers essential oil. The main biological activities were toxicity and repellence. Terpenes present in the essential oil were identified by GC-MS, and some authentic samples were tested to assess their activity individually. The most acutely toxic compounds after 3 days were beta-pinene and pulegone. Most of the monoterpenes elicited symptoms indicative of neurotoxicity. The most repellent compound was alpha-terpineol. Toxic and repellent effects of chemical derivatives of the major sesquiterpene present in B salicifolia essential oil, as well as a series of monoterpenes, were evaluated in order to investigate structure-activity relationships. The reduced derivatives of the monoterpenes and sesquiterpenes were more repellent that their carbonyl analogues. In addition, unsaturation in the germacrane skeleton enhanced repellent activity.     

Synergism of insecticidal action and effects on detoxifying enzymes in vivo of lambda-cyhalothrin and malathion by some nitrogen heterocycles in resistant and susceptible strains of Tribolium castaneum

The interactions of the synthetic pyrethroid, lambda-cyhalothrin and malathion were studied with purines, pyrimidines, caffeine and some other related nitrogenous compounds in resistant and susceptible strains of Triboliurn castaneum (Herbst.) The results were compared with those obtained with a known synergist, piperonyl butoxide (PBO) and precocene I. Adenine, cytosine, guanine, thymine and uracil synergised lambda-cyhalothrin, especially in the susceptible strain, with maximum effect at a 1:1 mass ratio, with the effect decreasing with increasing proportion of the heterocycle. The order of synergism of lambda-cyhalothrin was; precocene I > PBO > the nitrogenous compounds, in both resistant and susceptible strains. On the other hand, caffeine (lethal effect increased about twice), barbital (about twice), isobarbituric acid (less than twice) and bromacil (up to eight times) synergised malathion in malathion-resistant strains and antagonised in the susceptible strains. Total in-vivo esterases, carbox-ylesterases and cytochrome P₄₅₀ of susceptible and resistant strains showed significantly increased activity or content when treated with either insecticide plus a heterocyclic compound. Exceptions were with bromacil and malathion and for the malathion-specific strain, Kano-C with malathion and the N-heterocycles.     

Effect of fungal metabolites and some derivatives against Tribolium castaneum (Herbst) and Nezara viridula (L.)

Two fungal metabolites, aspyrone (3-(1,2-epoxypropyl)-5-hydroxy-6-methyl-5,6-dihydropyran-2-one) and asperlactone (3-(1,2-epoxypropyl)-5-(1-hydroxyethyl)-5-furan-2-one) were isolated from an Aspergillus ochraceus Wilhelm strain showing IGR activity against Tribolium castaneum (Herbst). Synthetic derivatives of aspyrone were produced using published methods. These derivatives together with aspyrone and asperlactone were tested for insect growth-regulating activity against T. castaneum, and for ovicidal activity against Nezara viridula L. Of the compounds tested asperlactone appeared to be the most active.