赤眼蜂早期低量释放的大田试验

1978—1983年,作者在河南省进行了早期低量释放赤眼蜂防治玉米螟和稻纵卷叶螟的试验。并与常规释放法作比较。早期低量释放区于4月下旬每亩释放500—1000头,常规释放区于5月底每亩释放10000头,第一代、第二代两种释放方法玉米螟卵块寄生率差异不显著。防治稻纵卷叶螟也得到相同结果。     

几株高效苏云金杆菌菌株对玉米螟、棉铃虫、粘虫和黄地老虎的毒力测定

本文以玉米螟、棉铃虫、粘虫和黄地老虎为供试昆虫，对筛选出的７株高效苏云金杆菌菌株的孢晶制剂进行了毒力测定。以ＬＣ５０为衡量各菌株的毒效指标，属血清型Ｈ６的“Ｇ０２”菌株对上述４种供试昆虫的毒力最高，属血清型Ｈ３ａ３ｂ的“８０－１”菌株对棉铃虫和粘虫的毒力也高于“ＨＤ－１”菌株。这一研究结果为今后生产高效的苏云金杆菌制剂及生产菌株的轮换提供了后备菌株     

Monitoring Cry1Ab susceptibility in Asian corn borer (Lepidoptera: Crambidae) on Bt corn in the Philippines

Between 2002 and 2004, collections of egg masses of Asian corn borer (ACB), Ostrinia furnacalis (Guenée) were made from corn-planting sites on the major Philippine islands of Luzon (Laguna, Pangasinan, Camarines Sur and Isabela provinces) and Mindanao (Bukidnon and South Cotabato provinces). The resulting neonates were bioassayed for susceptibility to Bacillus thuringiensis (Bt) Cry1Ab protein. The median lethal concentrations (LC₅₀s) for the different collections ranged from 0.42 to 2.37 ng/cm². The bioassay results suggest that Philippine corn borer populations were highly susceptible to Cry1Ab protein prior to the widespread deployment of Bt corn. The upper limit of the estimated LC₉₉ (104 ng/cm²) from the pooled bioassay data was selected as a candidate diagnostic concentration and subsequently tested on eleven ACB populations. Results of the validation assays showed that the mortality response of all the tested ACB populations was higher than the expected mortality (99%). Therefore, the concentration of 104 ng/cm² was used to monitor susceptibility in ACB populations in the Philippines. Monitoring of field populations during 2009 in areas where Bt corn had been grown for 3 years found some enhanced survival of neonates at the diagnostic concentration but progeny of the diagnostic-concentration survivors did not survive on Bt corn, indicating that ACB populations in the Philippines remain susceptible to Cry1Ab-containing Bt corn hybrids.     

球孢白僵菌胞外蛋白酶和几丁质酶活性与对亚洲玉米螟毒力的相关性分析

以振荡摇瓶培养法培养17株球孢白僵菌(Beauveriabassiana),分析其总胞外蛋白酶和几丁质酶的产生水平,同时用这些菌株的分生孢子粉作为样品,用人工饲养的亚洲玉米螟5d龄幼虫作为试虫,作毒力生物测定。并分析各个因素之间的相关性,验证各个酶活性指标作为毒力的生物测定的替代或者补充指标的可能性。结果表明,菌株间同代毒力、酶活之间的差异比较大,LT50的变化范围为4.82~10.06d,胞外蛋白酶活性的变化范围是0.86×10-2~3.66×10-2IU/mL,胞外几丁质酶活性的变化范围是0.012~1.47IU/mL。将后二者分别与各个菌株对玉米螟的LT50进行回归分析,结果发现胞外蛋白酶活性和胞外几丁质酶活性以及测定胞外蛋白酶活性时的干物质增重3个指标,与感染的亚洲玉米螟幼虫的死亡率及LT50的相关性都不显著,不能作为对亚洲玉米螟毒力的生物测定的替代或补充指标。     

影响松毛虫赤眼蜂防螟效果的主要因素

阐述了蜂种、育蜂质量、田间释放技术、田间环境条件、天敌、化学农药、玉米螟种群基数等因素对松毛虫赤眼蜂防治玉米螟效果的影响,并总结出提高松毛虫赤眼蜂防治玉米螟效果的有效措施:努力提高蜂种、育蜂质量;尽量减少田间的环境条件、天敌、化学农药因素对赤眼蜂的影响。     

亚洲玉米螟越冬关键生物控制因子研究

连续4年对沈阳地区亚洲玉米螟Ostrinia furnacalis(Guenée)越冬幼虫越冬后存活及发育情况研究表明,亚洲玉米螟幼虫越冬死亡率在45%～65%之间;白僵菌Beauvaria bassiana、寄蝇和茧蜂是导致亚洲玉米螟幼虫越冬死亡的主要病原菌和天敌种类,3类生物致死因子的综合控制力为22.50%～34.11%;3种生物致死因子年度间组成比例变异较大,存在互补和竞争效应,越冬后发生时期不同,白僵菌主要发生于发蛾高峰期前,茧蜂羽化期在发蛾高峰期后,寄蝇羽化期晚于白僵菌而早于茧蜂,白僵菌有越冬后再次侵染越冬代幼虫的条件;亚洲玉米螟室温下羽化期为18 d左右,雄蛾羽化和结束时间早于雌蛾,雌雄性比年度间差异较大。     

南充市应用生物导弹防治玉米螟效果和效益研究(英文)

为了推进"绿色植保",减少农药用量及残留和环境污染与防治成本,确保玉米生产、品质和生态环境安全,促进玉米增产增收,采用灯下诱蛾和田间剥查与试验示范相结合等方法,开展生物导弹防治玉米螟效果和效益研究。结果表明,每公顷投放生物导弹30～37对,平均防效78.0%,防治成本139.50～172.50元,比化学农药防治少142.50～168.00元,玉米产量比空白对照区平均高817.8 kg,增产11.0%,增加产值1 799.16元,增收节支1 941.66～1 967.16元。2003～2014年累计示范推广24 507.33 hm2,增产2004.21万kg,新增产值44 09.26万元,节省防治费用349.23～411.72万元,增收节支4 758.49～4 820.98万元,减少农药5%杀虫双大粒剂551.41 t或90%杀虫单使用12.87 t。且生物导弹使用简便,劳动强度小,适于老、弱、妇、幼操作,对人畜和环境安全,节省药械和用水,是有机农业、现代农业、绿色和无公害农产品及IBM绿色防控示范园区防治玉米螟、减少化学农药的理想替代产品。     

转基因抗虫耐除草剂复合性状玉米‘双抗12-5’对亚洲玉米螟的抗性及对草甘膦的耐受性研究

通过田间接虫、室内生测以及田间植株喷施草甘膦试验,在吉林省公主岭市综合评价了转cry1Ab/cry2Aj和G10evo-epsps基因抗虫耐除草剂复合性状玉米‘双抗12-5’对亚洲玉米螟[Ostrinia furnacalis(Guenée)]的抗性以及对草甘膦的耐受性,为‘双抗12-5’在吉林省产业化应用提供基础科学数据。结果表明,与非转基因对照‘郑单958’相比,‘双抗12-5’全生育期对亚洲玉米螟都具有良好的抗性,达到高抗水平;取食‘双抗12-5’心叶、雄穗及花丝等组织7d后的亚洲玉米螟幼虫存活率为4%~12%,而取食‘郑单958’各个组织的亚洲玉米螟幼虫存活率均高于96%。‘双抗12-5’在喷施推荐剂量(1 230g/hm2)及在2倍推荐剂量(2 460g/hm2)草甘膦情况下,4周内均生长正常,受害率为0;对照‘郑单958’植株第一周即表现出明显的药害症状,逐渐枯萎死亡,受害率达到100%。综上所述,‘双抗12-5’在吉林省表现出良好的抗虫性和除草剂耐受性。     

The influence of post-exposure temperature on the toxicity of insecticides to Ostrinia nubilalis (Lepidoptera: Crambidae)

The influence of post-treatment temperature on the toxicities of two pyrethroids (lambda-cyhalothrin and bifenthrin), a carbamate (methomyl) and a spinosyn (spinosad) to Ostrinia nubilalis (Hubner) larvae was evaluated in laboratory assays. From 24 to 35 degrees C, the toxicities of the pyrethroids decreased 9.5- and 13.6-fold while spinosad toxicity decreased 3.8-fold. The toxicity of methomyl did not change significantly. The results demonstrate that the most effective insecticide against a pest may vary with environmental conditions. In situations where comparable products from multiple insecticide classes are available, temperature should be included as a factor in the decision-making process.