Analysis of sex pheromone production and field trapping of the Asian corn borer(Ostrinia furnacalis Guenée)in Xinjiang,China

Identifying the sex pheromone systems of local pest populations facilitates their management,especially for moth species that show significant geographic variation in sex pheromone communication.We investigated the pheromone production and behavioral responses of the Asian corn borer(Ostrinia furnacalis Guenée;ACB)in Xinjiang,China.The ACB produces three compounds:(Z)-12-tetradecenyl acetate(Z12-14:Ac)and(E)-12-tetradecenyl acetate(E12-14:Ac)which are two sex pheromone compounds,and n-tetradecyl acetate(14:Ac)which has variable roles in mediating behavioral responses.The ratios of these three compounds produced in female gland are geographically distinct among different populations.Quantitative analysis of pheromone production showed that the proportions of Z12-14:Ac in the E/Z isomers(i.e.,Z and E12-14:Ac)and the proportions of 14:Ac in the ternary blend respectively averaged 60.46%(SD=5.26)and 25.00%(SD=7.37),with their probabilities normally or near-normally distributed.Trapping experiments in a cornfield indicated that deploying the E/Z isomers and the three compounds in rubber septa close to their gland ratios yielded the most captured males,while other ratios that deviated from the gland ratios showed reduced field captures.The ternary blend was significantly more attractive to males than the E/Z isomers in the field,indicating a functional role of 14:Ac as the third pheromone component used by the local population.Additionally,the dose-response test demonstrated that the application of the three compounds at dosages between 200 and 350μg attracted significantly more males compared to other dosages.Therefore,the characterization of this local ACB pheromone system provides additional information about its geographic variation and serves as a basis for optimizing the pheromone-mediated control of this pest in Xinjiang.

TEMPERATURE DEPENDENT DEVELOPMENT OF ASIAN CORN BORER Ostrinia furnacalis

Temperature dependent development in the Asian corn borer, Ostrinia furnacalis (Guenee) was determined at nine constant temperatures between 10℃ and 34℃. Except for 10℃ development of all life stages occurred at the temperatures tested, however, mortality was significantly great at the extreme temperatures(12℃ and 34℃). Egg, larvae and pupae duration accounted for 17%, 57% and 25% of total one of immature stage, respectively Lower developmental thresholds estimated to be 10 38, 10 06 and 11 07℃ for eggs, larvae and pupae, respectively. Upper limited thresholds were 28 00, 31 00 and 31 00℃ for eggs, larvae and pupae, respectively. The heat unit requirements for egg stage were 79 15 degree days, for larval stage were 339 73 degree days, and for pupal stage were 128 82 degree days, respectively. Overall, heat unit requirements for development from egg to adult were 539 91 degree days between lower developmental threshold 10 35℃ and upper limited threshold 32℃.

Progress on Sex Pheromone Synthesis of Asian Corn Borer, Ostrinia furnacalis (Guenee)

The progress on the components identification, synthesis methods （syn- thetic strategy of carbon chain increasing and synthetic strategy of carbon chain de- creasing） of Asian corn borer （Ostrinia fumacalis （Guenee）） sex pheromone was reviewed, which will provide a reference for the control of Asian corn borer.

Effects of Droplet Distribution on Insecticide Toxicity to Asian Corn Borers(Ostrinia furnaealis) and Spiders(Xysticus ephippiatus)

Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the second generation of Asian corn borer （ACB） larvae and their toxicity to spiders were studied. When insecticides were sprayed downwards into the maize canopies, randomly filtering out droplets by upper leaves led to great variations of droplet coverage and density within the canopies. Consequently, the efficacies of lambda-cyhalothrin and emamectin benzoate against ACB larvae were decreased because of randomly filtering out droplets by upper leaves. But field investigation showed that lambda-cyhalothrin was extremely toxic to hunting spiders, Xysticus ephippiatus, and not suitable to IPM programs in regulation of the second generation of ACB. Therefore, randomly filtering out droplets by upper leaves decreased lambda-cyhalothrin＇s efficacy against ACB larvae, but did little to decrease its toxicity to X. ephippiatus. Amamectin benzoate can reduce the populations of X. ephippiatus by 58.1-61.4%, but the populations can recover at the end of the experiment. Chlorantraniliprole was relatively safe to X. ephippiatus. It only reduced the populations of X. ephippiatus by 22.3-33.0%, and the populations can totally recover 9 d after application.

Migratory flight of insect pests within a year-round distribution: European corn borer as a case study

Insect migratory flight differs fundamentally from most other kinds of flight behavior, in that it is non-appetitive. The adult is not searching for anything, and migratory flight is not terminated by encounters with potential resources. Many insect pests of agricultural crops are long-distance migrants, moving from lower latitudes where they overwinter to higher latitudes in the spring to exploit superabundant, but seasonally ephemeral, host crops. The migratory nature of these pests is somewhat easy to recognize because of their sudden appearance in areas where they had been absent only a day or two earlier. Many other serious pests survive hostile winter conditions by diapausing, and therefore do not require migration to move between overwintering and breeding ranges. Yet there is evidence of migratory behavior engaged in by several pest species that inhabit high latitudes year-round. In these cases, the consequences of migratory flight are not immediately noticeable at the population level, because migration takes place for the most part within their larger year-round distribution. Nevertheless, the potential population-level consequences can be quite important in the contexts of pest management and insect resistance management. As a case study, I review the evidence for migratory flight behavior by individual European corn borer adults, and discuss the importance of understanding it. The kind of migratory behavior posited for pest species inhabiting a permanent distribution may be more common than we realize.

Detection of Resistances of Different Corn Varieties to Corn Borer

In order to practice integrated management of corn insect pests effectively, a field experiment was made to study the resistances of 33 corn varieties to corn borer （ Ostrinia furnacalis） in the corn area to the north of the Huaihe River in Anhui Province. The results showed that there were evident differences in resistances of different corn varieties to corn borer and the resistant levels of the same corn variety to corn borer were also different in the whorl stage and the ear stage. In the whorl stage of corn, eight corn varieties, ＇ ‘Zhongnougda 311＇, ‘Zhongke 11＇, ‘ Denghai 3＇, ＇ Dongdan 80＇ , ‘ Liyu 16＇, ‘ Zhengdan 23＇, ‘ Jidan 8＇ and‘ Huayu 13＇ preformed relatively stronger resistance to corn borer. In the ear stage of corn, five corn varieties of ‘ Xundan 20＇, ‘ Qidan 1 ＇, ‘ Zhongke 4＇, ‘ Nongda 108＇ and ＇ Ludan 6018＇ showed relatively stronger resistance to corn borer. The comprehensive resistances of ten corn varieties to corn borer in the whorl stage and the ear stage successively were ‘Zhongnongda 311’ 〉 ‘Zbong, ke 4＇ 〉 ‘Jidan 8＇ 〉 ‘ Zhengdan 23＇ 〉‘Zhengdan 958＇ 〉 ‘ Qidan 1＇ 〉 ‘ Zhongdi 985＇ 〉 ‘Nongda108＇ 〉 ‘Liyu16＇ 〉‘Denghai3＇.

The Impact of Beauveria bassiana, Bacillus thuringiensis （Bt） Spray, Trichogramma pretiosum and Spinosad on the Lepidoptera： Crambidae, European Corn Borer （Ostrinia nubilalis）

The research cxamined the effects of microbial and novel insecticidal control strategies and also Irichogramma pretiosum on the I,epidoptera： Crambidae, the European corn borer （ECB）, （Ostrinia nubilalis）. The treatments included ~ino^d, from bacteria the entomopathogenic fungus Beauveria bassiana, the egg parasitoid Trichogramma pretiosum, and foliar applied Bt spray, and t^vo combinations Bearveria bassiana plus Bt spray and Trichogramma pretiosum and spinosad. The infestations by the European corn borer larvae on stalks of corn were very＂ severe in all the control treatments both 2006 and 2007. The microbial treatments caused various levels of European corn borer mortality. In all the parameters there was a significant difference between the control and other treatments with a P 〈 0.00 l. In this research, treatment with spinosad emerged as the most effective biological agent in the control of the European corn borer. The treatments had no significant effects on the relative abundance and composition of non-target arthropods （P 〉 0.05）. This research is relevant in boosting underutilized control strategies and increasing stakeholder adoption of integrated pest management practices and thereby＇ reducing the use of conventional insecticides especially for orgamc thrmers. This is very important especially in certain countries where the commumities are skeptical about consuming transgenic crops.

Competitive interactions between invasive fall armyworm and Asian corn borer at intraspecific and interspecific level on the same feeding guild

Interspecific competition is an important factor in the population dynamics and geographical distribution of insect populations.Fall armyworm(FAW),Spodoptera frugiperda,an invasive species,and the Asian corn borer(ACB),Ostrinia furnacalis,a native pest species are major pests on maize in China,posing a threat to maize yield and grain quality.A series of laboratory,greenhouse,and field experiments were conducted to elucidate the competitive interactions between FAW and ACB.In the laboratory experiments,FAW exhibited aggressive behaviors more frequently when compared with ACB,while the latter species exhibited defense behaviors more frequently.Higher intraspecific competition was recorded in the FAW conspecific rather than in ACB,particularly in the 6th larval stage.FAW had a higher interspecific competitive advantage through intraguild predation over ACB,resulting in partial or complete displacement ACB when initially the ratio of the 2 species was 1:1.The interspecific competition also had significantly influenced on the population parameters,defensive enzymes,and nutrient of these 2 species.Competitive interaction proved that the response of superoxide,catalase,and soluble protein in FAW were significantly increased,whereas the total sugar content in both species was substantially decreased.Survival rate,and the plant damage that co-infested by both species varied significantly among the sequential combinations under greenhouse and field conditions.FAW consistently exhibited stronger intraspecific aggression than ACB under laboratory and field conditions when co-existing on the same feeding guild.These findings contribute to efforts toward the improvement of integrated pest management programs for FAW,in decision making for invasive and native pests’management strategies to reduce the high risks of FAW and ACB outbreaks.

Genome-wide screening and transcriptional profile analysis of desaturase genes in the European corn borer moth

Acyl-coenzyme A （Acyl-CoA） desaturases play a key role in the biosynthesis of female moth sex pheromones. Desaturase genes are encoded by a large multigene family, and they have been divided into five subgroups on the basis of biochemical functionality and phylogenetic affinity. In this study both copy numbers and transcriptional levels of desaturase genes in the European corn borer （ECB）, Ostrinia nubilalis, were investigated. The results from genome-wide screening of ECB bacterial artificial chromosome （BAC） library indicated there are many copies of some desaturase genes in the genome. An open reading frame （ORF） has been isolated for the novel desaturase gene ECB ezi-A11~ from ECB gland complementary DNA and its functionality has been analyzed by two yeast expression systems. No functional activities have been detected for it. The expression levels of the four desaturase genes both in the pheromone gland and fat body of ECB and Asian corn borer （ACB）, O. furnacalis, were determined by real-time polymerase chain reaction. In the ECB gland, All is the most abundant, although the amount of A14 is also considerable. In the ACB gland, A14 is the most abundant and is 100 times more abundant than all the other three combined. The results from the analysis of evolution of desaturase gene transcription in the ECB, ACB and other moths indicate that the pattern of A 11 gene transcription is significantly different from the transcriptional patterns of other desaturase genes and this difference is tied to the underlying nucleotide composition bias of the genome.

山东省玉米螟灾害风险评估与区划研究

针对山东省农业病虫害的危害评估及预防需求,对近年来山东省玉米螟(Pyrausta nubilalis)灾害进行风险评估与区划。结合中华人民共和国农业行业标准——《玉米螟测报技术规范》(NY/T 1611—2008)及山东省植物保护总站的玉米螟发生程度分级地方标准,在对山东省近13年玉米螟发生情况进行统计和数据提取的基础上,提出了以被害株率为主要划分因子及百株虫量为辅助因子的玉米螟发生程度分级准则,并以山东省16个地市为单元,进行了玉米螟的发生程度定级与频数统计;在以玉米螟发生频数为致灾因子、玉米播种面积及气象条件为孕灾环境因子、玉米产量为承载体因子的指标体系建立的基础上,进行了单指标因子风险区划的构建,并通过归一化处理,计算出综合风险指数,并根据综合风险指数生成山东省玉米螟综合风险区划。结果表明,山东省玉米螟灾害风险主要发生在该省中西部地区,其中,菏泽市为高风险区,德州市、潍坊市、滨州市及聊城市为较高风险区。

丹东地区鲜食玉米生产玉米螟的发生与防控

丹东地区鲜食玉米生产面积逐年增加,经济效益显著。由于鲜食玉米茎秆和果穗适口性好,在整个生育期内易遭受玉米螟的危害,严重影响鲜食玉米的产量、品质和商品性。文中对丹东地区鲜食玉米玉米螟发生情况进行了总结并有针对性地提出了防控措施,以期为丹东地区鲜食玉米种植提供参考。

亚洲玉米螟性信息素鉴定及其应用研究进展

【目的】综述近年来国内外关于亚洲玉米螟性信息素鉴定、综合防控及应用的研究进展,为亚洲玉米螟的监测预警、绿色防控等技术提供参考依据。【方法】运用文献统计学方法收集资料及调研,分析国内外亚洲玉米螟性信息素防治技术研究与应用的进展。【结果】亚洲玉米螟在中国、韩国、日本、菲律宾等国家均有分布,雌性个体通过释放性信息素吸引雄性继而交配;鉴定亚洲玉米螟主要性信息素组分为顺/反-12-十四碳烯醇乙酸酯(Z/E-12-14:Ac)和正十四碳醇乙酸酯(14:Ac),各组分作用不同,组分间比例存在地理种群差异;亚洲玉米螟性信息素产品已运用于监测、诱杀与交配干扰中,与其它防治技术相结合的集成技术防效显著;应用过程中存在多种影响性信息素诱剂诱捕效率的因素,包括性信息素剂量、诱捕器类型、放置高度、颜色及环境等。【结论】亚洲玉米螟在多个国家的玉米种植区均有分布,亚洲玉米螟性信息素比例存在地理种群差异,利用性信息素最佳组分系统结合影响性诱剂诱捕效率的多种因素,在田间防控亚洲玉米螟取得了较好效果,我国已组装、集成一套基于性信息素防控亚洲玉米螟绿色防治技术。

伊宁县玉米螟大发生原因分析及防治效果

伊犁河谷是新疆的主要粮食基地,随着市场需求变化和农区畜牧业发展的需要,伊犁河谷玉米种植面积呈现出井喷式发展。从2007年的6.93×10^(4)hm^(2)增加到2022年2.41×10^(5)hm^(2),增幅达到248.2%。伊宁县是伊犁河谷玉米种植大县,玉米种植面积4.7~5.3×104hm2,2016年由于玉米螟大发生导致产量严重下降到504kg·667m^(-2)。本文从气候条件、玉米螟越冬基数等方面进行分析,阐明伊宁县玉米螟大发生的原因,并从玉米产量的变化对防治措施和防治效果进行论述。

Occurrence Law of Armyworm in China and Its Identification and Prevention

Armyworm occurs throughout the world, which mainly causes damage on grasses. The morphology characteristic of armyworm is introduced, which is also compared with the morphology characteristic of the other insects such as corn borer, Leucania Ioreyi （Duponchel） and Leucania venalba. The occurrence law, living habit and prevention measures of armyworm in China are summarized, which will provide the foundation for worldwide further research on armyworm.

我国赤眼蜂工厂化繁育技术改进及防治农业害虫应用现状

自20世纪50年代,我国即开始系统研究赤眼蜂的人工繁育与田间释放应用技术,在适于赤眼蜂规模化繁殖的中间寄主种类研究与应用方面取得了举世瞩目的成就。近几年,我国在利用大卵(柞蚕卵)和小卵(米蛾卵)为中间寄主工厂化繁育赤眼蜂技术方面取得了一些进展。本文从大卵繁蜂涉及的配套生产设备、生产工艺以及小卵繁蜂过程中的幼虫人工饲料配方、饲养盘和成蛾收集技术方面取得的进展进行了归纳,并介绍了一次长效放蜂技术和大、小卵蜂混合释放技术在玉米螟和水稻二化螟防治的应用。2004年以来,吉林省累计推广松毛虫赤眼蜂防治玉米螟近1300万hm2,我国在推广应用赤眼蜂防治农业害虫方面取得巨大成功。最后,对赤眼蜂工厂化生产中存在的技术问题以及发展方向进行了探讨。

玉米种质资源对六种重要病虫害的抗性鉴定与评价

在2003-2005年间,对604份玉米种质进行了抗弯孢菌叶斑病和玉米螟鉴定,筛选出抗弯孢菌叶斑病的材料93份,抗玉米螟材料22份。2006-2009年间,对836份玉米种质进行了抗大斑病、茎腐病、穗腐病和瘤黑粉病的鉴定与评价,筛选出一批高抗和多抗的资源。在836份资源中,对大斑病1、2和N号3个生理小种具有抗性的材料均为50%左右;抗茎腐病材料为41.3%,高抗和抗性种质分别为264和81份;穗腐病高抗和抗性种质分别为5和171份,占比为21.1%;瘤黑粉病高抗和抗性种质各261和14份,占总鉴定材料的32.9%。上述结果表明抗大斑病、茎腐病和瘤黑粉病的种质资源较为丰富。通过对抗性结果进行对比分析,发现不同生态区玉米种质的抗性强弱以及抗性多样性存在明显差异,黑龙江和内蒙古的种质对病虫害的抗性强弱及多样性程度明显高于四川种质。此外,玉米自交系对病虫害的抗性强弱以及多抗性程度高于农家种。

吉林省玉米螟生物防治现状与展望

玉米螟是吉林省玉米生产中的最重要虫害,常年玉米为害损失率达10%以上。自20世纪80年代初吉林省就积极探索玉米螟的生物防治技术,积累了一定的生物防螟经验。本文就吉林省玉米螟研究中的几个主要热点问题:玉米螟的发生及危害现状、生物防治的主要技术、取得的经验和效益等进行综述,同时对今后开展玉米螟生物防控的研究方向进行了展望,以期为植保工作中病虫害绿色防控提供参考。

小型无人机低空喷洒在玉米田的雾滴沉积分布及对玉米螟的防治效果初探

2012年8月在河南省夏玉米生长中后期,利用Af-811小型无人机喷洒毒死蜱不同剂型开展了玉米螟防治试验。结果表明:(1)在试验设定的3个飞行高度中,喷雾高度2.5m时10%毒死蜱超低容量液剂的防治效果最好,达到80.7%;此时,农药雾滴在玉米雌穗部位达到15.6个/cm2。(2)无人机喷洒10%毒死蜱超低容量液剂对玉米螟的防治效果为80.7%,而42%毒死蜱乳油对水稀释药液的防效只有69.1%,而当往42%毒死蜱乳油药液中添加雾滴蒸发抑制剂后,防效增加到75.8%。本次试验中,小型无人机的飞行速度为5m/s,流量为1L/min,施药液量为0.42L/667m2,处理667m2需要25s,与地面自走式高杆喷雾机相比,省工、省时、省水,但从防效分析,无人机的喷雾技术还需要进一步优化。

玉米对亚洲玉米螟抗性的QTL分析

对玉米的亚洲玉米螟抗性进行遗传剖析对抗虫育种有重要意义。本研究以自330×K36的F2:3群体(114个家系)为材料,利用SSR标记对玉米的亚洲玉米螟抗性进行了数量性状位点(QTL)分析。结果表明,基于叶片侵害度性状检测到6个QTL,分别位于染色体4、6、7和10上;基于茎秆虫孔数性状检测到4个QTL,分别位于染色体1、5、8(2个)上;基于茎秆隧道长度性状检测到2个QTL,位于染色体1和8上;以隧道长度/虫孔数为鉴定性状检测到2个QTL,位于染色体7和10上。这些QTL所能解释的表型变异在10.3%～21.5%之间。大部分QTL的作用方式为部分显性。

东华北春玉米区玉米品种对主要病害和玉米螟的抗性评价

对东华北春玉米区24份玉米主栽品种进行玉米大斑病、弯孢菌叶斑病、灰斑病、丝黑穗病、茎腐病和玉米螟的抗性鉴定。高抗和抗大斑病品种11份,占参试品种的45.83%;高抗和抗灰斑病品种11份,占参试品种的45.83%;高抗和抗玉米弯孢菌叶斑病品种16份,占参试品种的66.67%;高抗和抗丝黑穗病品种10份,占参试品种的41.67%;高抗和抗茎腐病品种18份,占参试品种的75.0%;高抗和抗玉米螟品种6份,占参试品种的25.0%。综合抗性评价筛选出广谱抗性品种9份,占所有参试品种的37.5%。