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.

Control Effect of Bio-guide Wasp Virus Missile on Ostrinia furnacalis and Its Benefits for Maize Production in Nanchong City

In order to promote ＂green plant protection＂, reduce the administration dosage and residue of pesticides and control cost of environment pollution, and improve maize production, quality and agricultural ecological environment safety. In this study, the control effect and benefit of bio-guide wasp virus missile（BGWVM） on Ostrinia furnacalis in Nanchong City was investigated by using insect light traps and combined method of field investigation and experimental demonstration. According to the results, applying 30-37 pairs of BGWVM per hectare exhibited an average control efficiency of 78.0%, and the control cost was 139.50-172.50 CNY/hm2, which was reduced by 142.50-168.00 CNY/hm^2 compared with conventional chemical control. Average maize yield in BGWVM demonstration plot was 817.8 kg/hm2 higher and improved by 11.0% compared with blank control plot. The output value was improved by 1 799.16 CNY/hm^2 and the revenue increased by 1 941.66-1 967.16CNY/hm2. During 2003-2014, the cumulative demonstration and popularization area of BGWVM technique in Nanchong City had reached 24 507.33 hm^2, and the cumulative yield increment reached 20.042 1 million kg. BGWVM application improved total output value by 44.092 6 million CNY and saved control cost by 3.492 3-4.117 2 million CNY, thus increasing the revenue by 47.584 9-48.209 8 million CNY. BGWVM application reduced 551.41 t of 5% dimehypo GG or 12.87 t of 90%monosultap WP. In addition, BGWVM technique is simple to use, labor-saving and safe for human, animals, environment and crops, with significant economic, ecological and social benefits and without any side effect, which has become an ideal substitute for controlling O. furnacalis and reducing chemical pesticides in organic agriculture industry, modern agriculture industry, production of green and pollution-free agricultural products and IBM prevention and control demonstration gardens.

亚洲玉米螟Ostrinia furnacalis(Guenée)幼虫化学感受器种类与分布的形态学研究

用扫描电镜观察研究亚洲玉米螟幼虫的触角、口器附肢下颚须及其瘤状体、下唇须上的化学感受器的种类、分布与形态特征。亚洲玉米螟幼虫触角分为三节,在第二和第三节上主要有6个丹锥感受器和1个栓锥感受器两种化学感受器。口器附肢下颚须上有8个丹锥感受器,排列为3-2-2-1;下颚须瘤状体上各有一个侧栓锥和中栓锥感受器,另有一个较小的丹锥感受器;下唇须在第二节、第三节上各着生有一个丹锥感受器。亚洲玉米螟幼虫触角上化学感受器数量少,主要分为两种丹锥感受器和栓锥感受器;口器附肢下颚须及其瘤状体、下唇须上化学感受器数量较多,主要为丹锥感受器、侧栓锥和中栓锥感受器。

温度、相对湿度对亚洲玉米螟Ostrinia furnacalis(Guenée)越冬幼虫化蛹及羽化的影响

【目的】研究温度、相对湿度对亚洲玉米螟Ostrinia furnacalis(Guenée)越冬幼虫化蛹及羽化的影响。【方法】采用饱和盐溶液法研究不同温、湿度梯度下,新疆南北疆2个代表性玉米螟地理种群越冬幼虫化蛹和羽化的响应。【结果】越冬代玉米螟幼虫随着环境温(相对湿度)的增高(增大)化蛹、羽化进度随之缩短且差异显著(P<0.05)。较其他环境,28℃和75%RH,南疆种群、北疆种群玉米螟化蛹历期最短依次为(15.24%±3.02%)、(14.11%±2.64%)和(21.45%±2.54%)、(18.27%±1.96%),化蛹率和羽化率均最高分别为(90.12%、96.33%)和(76.22%±5.45%)、(74.12%±6.01%),(68.13%±3.77%)、(64.39%±4.72%)。【结论】温度、相对湿度是影响玉米螟化蛹和继后发育(羽化)的主要环境因子,新疆南疆种群、北疆种群越冬代老熟幼虫随着温度、相对湿度的升高化蛹和继后发育(羽化)的发生期呈“前移”趋势。

Determination and evaluation on field control efficacy of Trichogramma dendrolimi against Ostrinia furnacalis

The results of evaluation on field control efficacy of Trichogramma dendrolimi against Ostrinia furnacalis showed that the correction rates of Ostrinia furnacalis egg mass parasitism were 71.75% and 73.57%,the average control effect were 65.85% and 70.24%,the restoration yield loss rates were 6.78% and 7.97%,input-output ratio at 1:27.8 and 1:33.5 in Longjiang county of Heilongjiang province in 2009 and 2010,respectively.The technology is a integration of advanced,practical,environmental safety,effective biocontrol measures,embodies the "public plant protection,green plant protection" fully,has significant economic,social and ecological benefits.

Expression profiles and functional prediction of ionotropic receptors in Asian corn borer, Ostrinia furnacalis(Lepidoptera:Crambidae)

Genes involved in chemosensation are essential for odorant-mediated insect behaviors. Odorant receptors(ORs) bind and respond to pheromones and plant volatiles, regulating insect behaviors such as mating and host-plant selection, while ionotropic receptors(IRs), which are present at lower levels in insects than ORs, influence ion channels, especially in agricultural pests. Asian corn borer, Ostrinia furnacalis, is the main pest of maize that causes huge economic losses in Asia. Twenty-one Ofur IRs have been identified, but none has been characterized. In this study, tissue-specific expression profiling, phylogenetic analysis, and electroantennography(EAG) analysis were applied to characterize the evolution, expression, and the potential function of Ofur IRs. It was found that 20 Ofur IRs were highly expressed in the antennae, except for Ofur IR75p3, whereas 10 and nine Ofur IRs were highly expressed in the proboscis and genitalia, respectively, indicating that these Ofur IRs were functionally associated with feeding and oviposition. EAG results showed that seven acids elicited responses in the antennae of O. furnacalis and that 2-oxopentanoic acid displayed a significant femalebiased response. Combined with the phylogenetic analysis, 10 Ofur IRs in clade 4 were roughly predicted to be candidate receptors for 2-oxopentanoic acid and other tested acids. These results provide basic information about Ofur IRs and may help advance the knolwedge on the olfactory system of O. furnacalis.

Susceptibility of Ostrinia furnacalis to Bacillus thuringiensis and Bt Corn Under Long-Term Laboratory Selection

The susceptibility of the Asian corn borer, Ostrinia furnacalis to Bacillus thuringiensis (Bt) formulation and Bt corn was evaluated using insect bioassays for 6 years. Four strains of O. furnacalis were developed by laboratory selection from the laboratory strain reared on a non-agar semi-artificial diet. The RR-1 strain was exposed to a commercial formulation of B. thuringiensis subsp. kurstaki (Btk) incorporated into the artificial diet,the RR-2 strain was exposed to Bt corn (MON810) tissue incorporated into the diet, and the SS-1 and SS-2 strains were reared on the standard diet with or without non-Bt corn tissues material. Decreasing susceptibility of O. furnacalis to Bt and to Bt corn were found in each selected strain although the ED50 and larval weight fluctuated from generation to generation. The resistance of Bt-exposed strain (RR-1) to Btk increased 48-fold by generation 39; the Bt corn-exposed strain (RR-2) increased its resistance 37-fold to Btk by generation 24. No larvae of SS-1 survived when they were exposed to the leaves of Bt corn, Bt11 and MON810. However, 2-54% of the RR-1 (generation 46) and RR-2 (generation 20) larvae survived a 3 day-exposure to the leaves of Bt11 and MON810. The survival of both selected strains on Bt corn silk increased by 10-69%, and the larval weights after many generations selection were increased by 15-22% compared with the unselected susceptible strain. The young larvae were much more susceptible to Bt than older larvae. The highest mortality occurred when the larvae were exposed to Bt at the neonate stage. All of the results suggested that ACB could not only develop resistance to Bt preparation but also to Bt corn. Bt had significant effects on the growth and development of Asian corn borer than on the larval mortality. In order to maintain the long-term effectiveness of Bt pesticide and Bt corn, the resistance management should pay much attention to the larvae that may have opportunities to grow and developed on non-Bt corn or alternate hosts before they attack the Bt corn plants and the survival of larvae after Bt application.

Control Effect of Sex Pherom one Lure against the Asian Corn Borer( Ostrinia furnacalis) in Field

We studied the trapping effects on Ostrinia furnacalis from the aspects of different hanging heights and different color traps. The results suggested that the hanging height of 1.5 - 2.0 m received a better trapping effect, but trap color had little impact on trapping effect. The sex pheromone traps at different densities were placed in corn field. The results showed that sex pheromone lure could trap adult O. furnacalis, and it was feasible to apply sex pheromone in short term fore- cast. Meanwhile, it reduced the number of larvae and eggs, thereby reducing the damage of O. furnacalis. The lure number of 10 per hm2 was more appropriate, which could result in increasing yield of 8.61% compared with control

Occurrence Dynamics of Ostrinia furnacalis and Application Effect of Biological Control Technology in Wafangdian, Liaoning Province

In order to determine the population dynamics of Ostrinia furnacalis and reasons of local heavy occurrence in Wafangdian,Liaoning Province,adult sexual attraction monitoring and larva damage investigation of O.furnacalis were carried out from 2016 to 2018.The results showed that the initial occurrence period of overwintering adults of O.furnacalis in 2017 and 2018 was 10-16 d earlier than that in 2016,and the occurrence period of adults in the field was extended for 22-26 d,with three occurrence peaks of adults;the number of young larvae in corn field increased significantly in early September.In 2017 and 2018,the control effects of Trichogramma dendrolimi release on the first generation of O.furnacalis in 2017 and 2018 were 70.65%and 67.84%,respectively,lower than that in 2016(76.19%).It is speculated that the difference of annual climatic conditions and adjustment of local planting structure are the main reasons for population dynamic changes of O.furnacalis.

影响吉林省亚洲玉米螟〔Ostrinia furnacalis （Guenee）〕一代发生区发生量长期预测的关键因子──Ⅰ．发生程度与天敌及虫源基数的关系

玉米螟的发生程度与越冬种群的天敌和虫源基数密切相关，对越冬种群影响比较大的天敌有玉米螟厉寄蝇、玉米螟长距茧峰、细菌和白僵菌。其中影响最大的是白僵菌，在５月末至６月下旬发病，寄生率在不同年度间变化很大，变化范围在４．５％～９０％以上，对虫源基数有重大影响。玉米螟大发生必须有足够的有效虫源，在吉林省一代为主的发生区，６月份的越冬虫量为有效虫源，在不考虑降雨的情况下，６月中旬的百秆活虫量与７月份性诱蛾量及秋季百株虫量均极显著相关（相关系数分别为０．７０２３和０．８６９．构成大发生的有效上源数至少为每百秆有３０头以上；７月份的累计单盆诱蛾量在３００头以上。ａｎｄｒ＝０．８６９ｒｅｓｐｅｃｔｉｖｅｌｙ）ｅｘｃｅｐｔｗｅａｔｈｅｒｆａｃｔｏｒ．Ｌａｒｖａｅｎｕｍｂｅｒｐｅｒ１００ｓｔａｌｋｉｎｍｉｄｄｌｅＪｕｎｅａｎｄａｄｕｌｔｎｕｍｂｅｒｔｒａｐｅｄｂｙｐｅｒｐｈｅｒｏｍｏｎｅｔｒａｐｉｎＪｕｌｙｉｓａｔｌｅａｓｔｏｖｅｒ３０ａｎｄ３００ｒｅｓｐｅｃｔｉｖｅｌｙｉｎｈｅａｖｙｅｍｅｒｇｅｎｃｙｙｅａｒｓ．Ｋｅｙｗｏｒｄｓ：Ｏｓｔｒｉｎｉａｆｕｒｎａｃａｌｉｓ；Ｆｏｒｅｃａｓｔ；

Volatiles induced by the larvae of the Asian corn borer （Ostrinia furnacalis） in maize plants affect behavior of conspecific larvae and female adults

Effects of maize （Zea mays L.） volatiles induced by larvae of the Asian corn borer, Ostriniafurnacalis （Guenee）, on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investigated. Nineteen volatile chemicals, with terpenes being the major components, were identified from maize plants attacked by third instar Asian corn borer larvae. Coupled gas chromatographic-electroantennographic detection （GC-EAD） analyses revealed some electroantennographic differences between female and male Asian corn borer antennae in response to larvae-induced maize volatiles; female responded to （E）-2-hexenal, nonanal, （Z）-3-hexen-l-ol and three unknown compounds while the male only responded to （E）-2-hexenal, nonanal and one unknown compound. In laboratory orientation bioassays, Asian corn borer neonate larvae were attracted to extracts collected from Asian corn borer-damaged plants as well as to synthetic farnesene, but were repelled by （Z）-3-hexen- 1 -ol. In laboratory oviposition bioassays, gravid females laid fewer eggs on plants damaged by larvae than on mechanically damaged plants or undamaged plants. Adult Asian corn borer females deposited fewer eggs on wax paper treated with （E）-2-hexenal or （Z）-3-hexen-l-ol than on wax paper treated with hexane （control）. The results suggest that Asian corn borer can affect the behaviors of conspecific larvae and adults by changing host plant volatiles.

PLA_(2) mediates the innate immune response in Asian corn borer, Ostrinia furnacalis

The eicosanoid signaling pathway mediates insect immune reactions to a wide range of stimuli. This pathway begins with the biosynthesis of arachidonic acid (AA) from the hydrolysis of phospholipids catalyzed by phospholipase A_(2) (PLA_(2)). We report here that the PLA_(2) inhibitor, dexamethasone (DEX), impaired the innate immune response including nodulation, encapsulation, and melanization in Ostrinia furnacalis larvae, while AA partially reversed these effects of DEX. We cloned a full-length complementary DNA encoding a PLA_(2), designated as OfsPLA_(2), from O. furnacalis. The open reading frame of OfsPLA_(2) encodes a 195-amino acid residue protein with a 22-residue signal peptide. Sequence alignment analyses indicated that O. furnacalis PLA_(2) might be a Group III secretory PLA_(2). The highest transcript levels of OfsPLA_(2) were detected in the fat body, and its transcript levels increased dramatically after infection with Escherichia coli, Micrococcus luteus, or Beauveria bassiana. Recombinant OfsPLA_(2) significantly induced prophenoloxidase (PPO) activation in larval hemolymph in the presence of Ca^(2+) and encapsulation of agarose beads. Injection of recombinant OfsPLA_(2) into larvae resulted in increased transcript levels of attacin, defencin, and moricin-3 genes. Our results demonstrate the involvement of the eicosanoid signaling pathway in the innate immune response of O. furnacalis larvae and provide new information about the roles of O. furnacalis secretory PLA_(2) in activating PPO and antimicrobial peptide production.

A dsRNA-degrading nuclease(dsRNase2)limits RNAi efficiency in the Asian corn borer(Ostrinia furnacalis)

The efficiency of RNA interference(RNAi)varies substantially among different insect species.Rapid degradation of double-stranded RNA(dsRNA)by dsRNA-degrading nucleases(dsRNases)has been implicated to cause low RNAi efficiency in several insect species.In this study,we identified four dsRNase genes(OfdsRNaseL Ofd-sRNase2,OfdsRNase3 and OfdsRNase4)from the Asian corn borer(Ostrinia furnacalis)transcriptome database.Bioinformatic analyses showed that each deduced protein sequence contained endonuclease NS domains and signal peptides.Gene expression analysis revealed that OfdsRNase2 was exclusively expressed in the midgut of larvae.RNAi efficiency was investigated in 2-d-old fifth-instar larvae(high expression of dsRNase2)and 2-d-old pupae(low expression of dsRNase2)by feeding or injecting dsRNA targeting a marker gene that encodes the lethal giant larvae protein(OfLgl).Our results showed that OfLgl only partially silenced the expression of OfLgl in pupae,but not in larvae,suggesting that OfdsRNase2 could contribute to lower RNAi efficiency in larval stages.This hypothesis was supported by our RNAi-of-RNAi experiment using a tissue culture technique where the silencing efficiency against the reporter gene,OfHexl,was significantly improved after knockdown of OfdsRNase2.When double luciferase assays were performed to evaluate the role of the four dsRNases in vitro,only OfdsRNase2 expressed in S2 cells significantly affected RNAi efficiency by degrading dsRNA.Taken together,our results suggested that the degradation of dsRNA by OfdsRNase2 in the midgut contributed to low RNAi efficiency in O.furnacalis larvae.

亚洲玉米螟Ostrinia furnacalis Guenee幼虫取食位置初探

通过人工接虫、室内试验和田间调查的方法分析亚洲玉米螟幼虫的取食位置．结果表明幼虫在分散前集中在未抽出的雄穗上取食，分散后主要取食玉米中部的茎和雌穗；喇叭口期以前的幼虫为害虽然造成花叶，但其成活率很低，对玉米影响不大。建议在玉米抗螟性鉴定时应考虑玉米茎和雌、雄穗对幼虫的作用，在防治时采用喇叭口末期集中施药和抽雄期适当去雄的方法。

Molecular characterization of glutaredoxin 2 from Ostrinia furnacalis

Glutaredoxins(GRXs)play very important roles in maintaining intracellular redox homeostasis.In the present study,the full-length cDNA sequence encoding GRX2,named OfurGRX2(GenBank accession no.GU393246),was obtained from Ostrinia furnacalis,using reverse transcription polymerase chain reaction and rapid amplification of cDNA ends.Sequence analysis revealed that the open reading frame of OfurGRX2 consists of 351 nucleotides encoding 116 amino acid residues with a predicted molecular weight of 12.6 kDa.Homolog research revealed that OfurGRX2 shares a common active site,CPYC/CPFC,with other insect counterparts.Expression profiles revealed that OfurGRX2 is a ubiquitous gene expressed in insect heads,fat bodies,epidermises,mid guts and muscles.The OfurGRX2 transcript peaked in 36-h larvae of 4th instars,and then suddenly declined in the molting stage.Hormone treatment experiments revealed that 20-hydroxyecodyson(20e)significantly induces the expression of the OfurGRX2 transcript,whereas juvenile hormone(JH)counteracts 20e effects.Adverse stress factors(including starvation,ultraviolet light,mechanical injury,Escherichia coli exposure,and high and low temperatures)dramatically induced OfurGRXGRX2 transcript expression,which confirmed for the first time that GRX2 play important roles in insecta during exposure to adverse environments.

SEX PHEROMONE BIOSYNTHESIS IN ASIAN CORNBORER Ostrinia furnacalis——SEX PHEROMONE BIOSYNTHETIC PRECURSORS

Ⅰ. INTRODUCTION Many lepidopteran sex pheromones are biosynthesized from long chain saturated fatty acids by the combined steps of △11 desaturation, chain-shortening, reduction and acetylation. The formation of △5, △7, △9 and All pheromonal components can be explained by these biosynthetic steps. However, the biosynthetic pathway of

杀虫灯诱杀亚洲玉米螟和草地贪夜蛾的距离与性比研究

为明确杀虫灯对亚洲玉米螟Ostrinia furnacalis和草地贪夜蛾Spodoptera frugiperda的杀虫效果,分别对2种害虫人工饲养的成虫进行颜色标记后,在距频振式太阳能杀虫灯不同距离处释放,根据杀虫灯下回收数量确定有效防控距离。同时对高空测报灯和自动虫情测报灯2种不同光源测报灯诱集到的2种害虫的性比进行分析。结果表明,在距杀虫灯15~45 m内,亚洲玉米螟的回收率随着距离的增加呈上升趋势,距灯45 m的回收率最高,为4.95%,在距离增加到60 m时,回收率显著下降。草地贪夜蛾在距灯30 m处的回收率为6.08%,随着离灯距离的增加,雌、雄蛾回收率均呈下降趋势,且回收的雌蛾比例减少。杀虫灯在1.2 m高度时对亚洲玉米螟的回收率高于1.5 m和1.8 m,3个高度雄蛾的回收率均高于雌蛾,随着高度增加,回收率下降,雌蛾的回收比例也呈下降趋势。高空测报灯和自动虫情测报灯捕获的2种害虫雌雄性比均低于0.45∶1,2种害虫的趋光性均存在雄性偏好。

两种诱虫灯下亚洲玉米螟种群动态及迁飞状态分析

【目的】亚洲玉米螟(Ostrinia furnacalis)是我国玉米生产中最具毁灭性的鳞翅目迁飞害虫之一,严重威胁玉米安全生产,比较和评价地面灯和探照灯诱集的玉米螟种群动态和迁飞状态,为玉米螟精准防控技术制定和迁飞监测预警提供科学依据。【方法】2019—2023年连续5年在山东烟台利用地面灯和高空探照灯对玉米螟进行监测,每年4月1日至10月31日逐日检查并统计两种诱虫灯下的玉米螟数量,通过绘制监测曲线分析玉米螟的种群动态;根据每日诱虫量占全年诱虫量的百分比研究分析玉米螟的上灯规律;根据迁飞性昆虫种群数量“突增突减”现象,以及探照灯和地面灯诱虫数量比值,分析玉米螟的迁飞状态。【结果】玉米螟发生数量在年度间和月份间呈差异变化,且探照灯对玉米螟的诱集量高于地面灯,经Pearson相关分析,两种诱虫灯年诱虫总量之间不存在相关性;地面灯和探照灯监测的玉米螟种群动态基本一致,但探照灯诱虫高峰明显,且开始时间早,结束时间晚;地面灯和探照灯下玉米螟上灯规律一致,只有高峰日、一般发生日和不发生日3种类型,且高峰日均以7月中旬为分界点呈现前后两个高峰阶段;迁飞状态分析显示,玉米螟总体上分为两个迁飞过程,5月下旬至6月下旬为第一个迁飞过程,虫量少、历期短,7月下旬至9月中旬为第二个迁飞过程,虫量多、历期长。【结论】地面灯和探照灯下玉米螟种群动态一致,两种灯均可用于监测玉米螟发生动态,但探照灯诱虫数量多、诱虫高峰明显、第一个高峰日早、高峰历期长,在监测玉米螟早期迁飞状态方面更具优势,可及时监控玉米螟发生情况,并做好防控准备;地面灯和探照灯下玉米螟上灯规律一致,其高峰日均分前后两个高峰阶段,且高峰日状态明显,均可用于监测玉米螟上灯规律;玉米螟5月下旬至6月下旬经烟台从南往北迁飞,7月下旬至9月中旬往南回迁,可提前在玉米螟迁飞路径上加强监测预警,并开展精准防控工作控制玉米螟迁飞种群数量。

红火蚁对亚洲玉米螟的捕食作用及其发生影响

蚂蚁在蛀茎害虫的综合治理方面发挥着重要的作用。全球分布性的入侵蚂蚁红火蚁取食多种无脊椎动物并在入侵区域成为优势物种。但是目前尚不清楚红火蚁对玉米重要害虫亚洲玉米螟的捕食作用。本文在实验室和野外条件下研究红火蚁对亚洲玉米螟的觅食和捕食行为。研究显示,对于隐藏度低的亚洲玉米螟,红火蚁发现该害虫的时间约为40s,召集时间少于1 h。对于隐藏度高的亚洲玉米螟,红火蚁发现该害虫的时间超过26 min,召集时间接近6 h。野外实验显示,红火蚁可以降低玉米中后期生长阶段中50%的亚洲玉米螟卵块、94.1%的亚洲玉米螟幼虫和92.9%亚洲玉米螟蛀食孔。研究提供更多的视角理解红火蚁对生物多样性影响。

新疆亚洲玉米螟暴发成灾驱动机制分析及其治理对策

亚洲玉米螟Ostrinia furnacalis(Guenée)为新疆玉米生产中的主要害虫,2010年以来呈整体暴发态势,并造成了极为严重的产量损失,已成为制约当前新疆玉米高产稳产和粮食产能提升最重要的害虫,然而有关其暴发成灾的驱动机制尚不清楚。为此,本文通过分别概述近年来新疆气候、作物种植结构、栽培耕作措施以及亚洲玉米螟田间发生世代的变化情况,综合分析了上述变化对亚洲玉米螟越冬幼虫存活、个体生长发育、取食偏好和种群增殖扩张等方面造成的具体影响。在此基础上,结合已有大量研究成果,系统解析了新疆绿洲生态区亚洲玉米螟种群暴发成灾的驱动机制。此外,本文还介绍了新疆植保科技工作者在亚洲玉米螟综合治理技术研究与应用方面取得的相关成果,简述了田间治理采取的措施和取得的防治成效,最终为亚洲玉米螟的持续有效治理提供一定参考。