雅脊金小蜂长翅型雌蜂对米象种群的控制作用

雅脊金小蜂Theocolax elegans（West．）是我国南方重要仓储害虫米象Sitophilus oryzae（L．）的优势天敌。为了更好地保护和利用该蜂，采用单因子方差分析和ISD多重比较，在实验室内研究了雅脊金小蜂和米象的种群数量动态，以及该蜂长翅型雌蜂对米象种群的控制作用。结果显示，在温度25℃、相对湿度65％的条件下，雅脊金小蜂和米象的世代发育历期分别约为25天和40天。按照每盒1、2、4、8、16、32、64和128头接入的寄生蜂均可定殖，并对米象种群起着控制作用。其中，接蜂64头时，即寄生蜂与米象数量比为1：6时，控制效果最好，在放蜂后第10-50天内，控制效果迭89．11％-96．47％，与其它几组试验差异显著。试验结果表明，雅脊金小蜂可以有效地控制米象的发生与危害。     

蓝色长盾金小蜂生物学习性观察

蓝色长盾金小蜂Scutellista caerulea Fonscolombe是橡副珠蜡蚧Parasaissetia nigra Nietner的重要天敌之一。为了探明该蜂的生物学习性，作者在室内观察了该蜂的交配行为、寄生行为、发育及其对寄主龄期的选择性。结果显示：蓝色长盾金小蜂的交配行为包括搜寻与求偶、交尾前期、交尾、交尾后期4个阶段。小蜂的寄生行为分为搜寻寄主、触角检测、产卵针刺探、产卵、产卵后梳理5个过程；同一小蜂的寄生次数为1～3次，寄生时间随着寄生次数的增加而减少，超过3次时，寄生时间相对延长。在室温25℃～27℃，金小蜂世代发育经卵、幼虫、蛹、成虫共4个阶段，发育历期为28～30 d，其中卵期3 d，幼虫期9～10 d，蛹期16～17 d。蓝色长盾金小蜂对橡副珠蜡蚧黑色成虫的选择系数最高，为0.57，对初期成虫的选择系数最低，为0.07。寄主虫期对蓝色长盾金小蜂的发育与繁殖影响明显，在寄主为初期成虫至黑色成虫时，蓝色长盾金小蜂的发育历期随着寄主虫期的增大而缩短，出蜂数则呈上升趋势，发育历期以寄主为初期成虫时最长，为31.8 d，寄主为黑色成虫时最短，为27.5 d；出蜂数以寄主为黑色成虫最多，初期成虫最低；寄主虫期对蓝色长盾金小蜂雌性比无影响。综上所述，蓝色长盾金小蜂的寄生时间与寄生次数密切相关，黑色成虫期的橡副珠蜡蚧是最适宜寄主，研究结果可为该蜂进一步扩繁利用提供依据。     

烟草甲的优良寄生蜂象虫金小蜂的生物学特性

本文研究了烟草甲Lasioderma serricorne（Fabricius）的寄生蜂象虫金小蜂Anisopteromalus calandrae（Howard）的生物学特性,包括在解剖镜下观察象虫金小蜂各虫态发育情况,发育历期,羽化、交配及产卵等行为,并观察补充营养（10%蜂蜜水）对象虫金小蜂成虫寿命和繁殖的影响。研究表明,该蜂主要寄生烟草甲的高龄幼虫和蛹,以老熟幼虫或蛹在寄主茧内越冬。在温度25℃,湿度70%,光周期16L：8D的条件下,各虫态的发育历期分别为卵期1.5 d,幼虫期5.9 d,蛹期9.9 d,成虫产卵前期0.9 d,成虫寿命15.1 d,完成一代需18.2 d。单雌出蜂量29～82头,平均54.75头。在25℃条件下,以10%蜂蜜水饲喂,成虫寿命为29.6 d,单雌平均出蜂量76.1头。以上结果表明,象虫金小蜂具有发育历期短,繁殖力高,搜索能力强等优点,是一种具有很大开发潜力的寄生性天敌。     

贵州烟仓害虫天敌种类及优势种的生物学特性

对贵阳地区的烟仓害虫天敌种类进行了调查.结果表明,其天敌共有11种,隶属3纲、7目、10科;优势种天敌为麦蛾柔茧蜂、米象金小蜂.麦蛾柔茧蜂完成一代夏季为9～13d,秋季为13～18d,一年发生世代数可达10代以上;成虫寿命12～17d.将采集的烟草粉斑螟幼虫于室内饲养,麦蛾柔茧蜂的出蜂率为46.0%;在烟仓的墙壁、过道和烟包表层,麦蛾柔茧蜂对烟草粉斑螟的平均寄生率达61.0%.米象金小蜂完成一代需30～33d,发生世代数3代;成虫寿命为10～15d.在烟仓,该蜂对烟草甲幼虫和蛹的寄生率分别为24.53%～33.70%、42.59%～61.64%.米象金小蜂对寄主烟草甲的跟随现象明显.     

大菜粉蝶颗粒体病毒与蝶蛹金小蜂在菜粉蝶生物防治中的相互关系

蝶蛹金小蜂寄生被大菜粉蝶颗粒体病毒(PbGV)严重感染的菜粉蝶蛹后,出蜂数、羽化率和性比分别由对照组的22.3头/蛹、99.8％和92.1％,下降至5.7头/蛹、51.6％和79.7％。由这些蛹育出的金小蜂雌蜂,存活期缩短、产仔数和寄生蛹数明显减少,但是其子代的发育历期、羽化率和性比,则不受影响。 PbGV包涵体直接被蝶蛹金小蜂成虫取食后,能显著延长其寿命,估计该病毒包涵体对金小蜂可能有一定的营养功能。蝶蛹金小蜂的寄生,可使带毒寄主蛹中PbGV包涵体含量下降25.2％。金小蜂雌蜂在带毒菜粉蝶蛹中产过卵后,部分个体能在随后的产卵活动中将病毒传给健康寄主,并引起发病。根据本文结果,作者认为:在菜粉蝶的生物防治中,只要掌握好病毒的施用时期,PbGV与蝶蛹金小蜂之间的关系,是可以协调的。     

快速评价内寄生蜂雌蜂携带因子生理活性的简易方法

介绍一种以γ-射线辐射处理雌蜂,评价内寄生蜂雌蜂携带因子生理活性的简易方法。该方法既能维持雌蜂正常的寄生能力和携带因子的生理活性,又能排除寄生蜂胚胎和幼虫来源因子对寄主的影响。当以150Gy剂量的γ-射线处理蝶蛹金小蜂雌蜂时,其存活率和产卵能力未受明显影响,但其子代胚胎不能发育。经辐射处理的雌蜂寄生菜粉蝶蛹后能象未处理正常蜂一样明显地抑制寄主的血细胞免疫,其引起寄主血细胞总数、组成、死亡率及浆血细胞延展率变化与正常蜂基本一致。结果表明,寄主蛹被寄生后其血细胞免疫受抑制主要是该蜂雌蜂携带因子引起的。最后讨论了使用该方法的注意事项。     

副珠蜡蚧阔柄跳小蜂对蓝色长盾金小蜂寄生橡副珠蜡蚧的干扰作用

为明确副珠蜡蚧阔柄跳小蜂Metaphycus parasaissetiae Zhang & Huang对蓝色长盾金小蜂Scutellista caerulea Fonscolombe寄生橡副珠蜡蚧Parasaissetia nigra Nietner的干扰作用, 于室内观察了寄主不同成虫阶段(产卵前期和产卵期)?副珠蜡蚧阔柄跳小蜂接蜂数量(3?10?20头和30头)?两种蜂接蜂间隔时间(2?4?6 d和8 d)等因素对两种寄生蜂寄生率和产卵量的影响?结果表明, 寄主发育阶段对蓝色长盾金小蜂产卵量和寄生率均无显著影响?随着副珠蜡蚧阔柄跳小蜂接蜂数增加, 蓝色长盾金小蜂的产卵量有所增加, 但增加不显著?副珠蜡蚧阔柄跳小蜂接蜂数为3~30头时, 蓝色长盾金小蜂寄生率均高于副珠蜡蚧阔柄跳小蜂; 接入副珠蜡蚧阔柄跳小蜂后再接蓝色长盾金小蜂时, 两种寄生蜂接蜂间隔时间对蓝色长盾金小蜂的寄生率及产卵量影响明显, 间隔2 d时蓝色长盾金小蜂产卵量最高, 为21.3粒; 间隔4 d时, 蓝色长盾金小蜂寄生率最高, 为58.89%; 但间隔8 d时蓝色长盾金小蜂的产卵量和寄生率下降至最低?研究结果表明, 接入副珠蜡蚧阔柄跳小蜂后再接蓝色长盾金小蜂时, 间隔时间在4 d内对蓝色长盾金小蜂没有影响, 间隔时间超过4 d时对蓝色长盾金小蜂有明显干扰, 试验结果可以为合理避免这两种寄生蜂种间竞争提供依据?     

管氏硬皮肿腿蜂的寄生特性

研究了管氏硬皮肿腿蜂对3种天牛和虫源较为丰富、取材较为容易的黄粉虫、家蚕、蜜蜂、松阿扁蜂、粘虫的寄生选择性，在不同寄主上的寄生特性以及寄主不同处理、寄主大小对其寄生的影响。结果表明：管氏硬皮肿腿蜂对不同供试昆虫的麻痹率和寄生率不同；在不同寄主上，管氏硬皮肿腿蜂的发育和繁殖特性不同。该蜂除偏爱寄生天牛幼虫和蛹外，对黄粉虫幼虫和蛹的寄生产卵率也较高，分别为80％、50％，可作为寄主繁蜂；对松阿扁叶蜂幼虫的麻痹率和寄生率均达65％以上，作为繁蜂替代寄主具有一定的潜力。用氯仿：酒精为1 ：10混合液处理桑虎天牛幼虫2h对肿腿蜂寄生率、单雌产卵量有明显的促进作用。寄主体重增加，可延长肿腿蜂雌蜂的产卵前期，增加单雌产卵量，提高子代蜂性比，但对各虫态发育历期影响不大。     

赣北稻负泥虫蛹寄生蜂调查初报

据初步观察,赣北稻负泥虫蛹寄生蜂有5科9种,总寄生率为52.58％。在9种寄生蜂中,绒茧蜂金小蜂、螟蛉绒茧蜂和负泥虫沟姬蜂为优势种,分布广,寄生率高,分别占负泥虫蛹寄生率的60.66％、21.62％和9.24％。其它6种共占8.48％。同时,寄生蜂寄生率高低,因地点、时间不同而异,喷洒乐果对负泥虫蛹寄生蜂无影响。     

赣北稻负泥虫蛹茧寄生蜂调查初报

据初步观察,赣北的稻负泥虫蛹茧寄生蜂有9种,总寄生率为52.58%。在9种寄生蜂中,初步认定绒茧蜂金小蜂、螟蛉绒茧蜂和负泥虫沟姬蜂为优势种,其寄生率分别为60.66%、21.62%和9.24%。其它6种共占8.48%。此外,寄生蜂寄生率的高低,因负泥虫蛹茧采集地点、采集时间不同而异,且喷洒乐果农药对负泥虫蛹茧寄生蜂无任何影响。     

Management of five stored-product insects in wheat with pirimiphos-methyl and pirimiphos-methyl plus synergized pyrethrins

Hard red winter wheat was treated with pirimiphos-methyl at 4, 6 and 8 mg kg(-1), synergized pyrethrins at 0.38, 0.75, 1.13 and 1.5 mg kg(-1), and combinations of the two insecticides, to conduct laboratory bioassays against four beetle pests of stored grain, red flour beetle Tribolium castaneum (Herbst), rusty grain beetle Cryptolestes ferrugineus (Stephens), lesser grain borer Rhyzopertha dominica (F), and rice weevil Sitophilus oryzae (L), and one moth pest, Indianmeal moth Plodia interpunctella (Hubner). Beetle adults and P interpunctella larvae survived well on control wheat, producing a large number of progeny (65-1037 insects per container). Kernel damage in control wheat among the insect species ranged from 9 to 99%. On pirimiphos-methyl-treated wheat, mortality of R dominica adults was > or =72%, but that of the other beetle species and P interpunctella larvae was 100%. Progeny were not produced on pirimiphos-methyl-treated wheat, and the kernel damage was negligible (< or =1%). Synergized pyrethrins were ineffective against the five insect pests. Pirimiphos-methyl combined with synergized pyrethrins was not superior to pirimiphos-methyl alone against the five insect pests. Pirimiphos-methyl is not registered in the USA for use on wheat, but our results suggest that it could be a viable grain protectant at rates of 4-8 mg kg(-1).     

稻谷在储藏期对玉米象的抗虫机制研究

本文选用抗、感各类的水稻品种(品系)22个,就所考察的13个稻谷物理化学因素彼此相互影响,刚逐步回归分析,研究稻谷在储藏期对玉米象的抗虫机制。结果表明,稻谷开裂率愈大,千粒重越重,则品种就愈有利于玉米象取食;开裂率愈大,谷粒愈宽,谷粒表面颊毛数愈少就愈有利于玉米象的产卵;直链淀粉含量越高,开裂率越大,品种的抗生性就愈低,愈有利于玉米象生长发育;相反,品种粗蛋白含量和粗脂肪含量越高,就愈不利于玉米象的生长发育。其它被测试的6个稻谷物理化学因素:谷粒长,谷粒长/宽,谷壳表面突起数,谷壳内、外颖壳厚度和总糖含量对稻谷在储藏期对玉米象的抗性无显著影响。     

Unusual behavior of oviposition and development of <Emphasis Type="Italic">Sitophilus zeamais</Emphasis> (Coleoptera: Curculionidae) in peach and apple fruits

The maize weevil Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae) is a worldwide pest on stored products, as maize, wheat and rice grains. However, in South Brazil, these weevils have been found attacking fruits in field conditions. It was reported that adults attack fruits to feeding, but there was no information of oviposition and larval development on these hosts. Furthermore, due to monitoring apple orchards, was observed that some fruits showed distinct kind of punctures, suggesting a oviposition by these weevils. The present study reports first record an unusual behavior of S. zeamais by oviposition and larval development in peach and apple fruits. The study was conducted in laboratory conditions (temperature: 25?±?1 °C, RH: 70?±?10% and photophase of 14 h). Peach and apple fruits were offered to S. zeamais females. The oviposition and duration of immature stages in peach were measured in fruits and in corn grains, used as control observation. The oviposition and larval development occurred in peach and apple fruits, with a development until to adult. The average of egg-to-adult was 47.4 d in peach and and 45.1 d apple fruits, respectively, while in corn grains, its natural host, the duration was 38.2 d. These results show that the damage caused by S. zeamais in peach and apple fruits may be due to oviposition and the development of immature stages. So, the novelty is in demonstrating that the maize weevil does not just feed as an adult opportunistically on the fruits, but can complete a full life cycle using fresh fruits.     

Extraction of allyl isothiocyanate from horseradish (Armoracia rusticana) and its fumigant insecticidal activity on four stored‐product pests of paddy

BACKGROUND: Isothiocyanates (ITCs) extracted from Armoracia rusticana Gaertn., May & Scherb. have been shown previously to have insecticidal activity. Allyl isothiocyanate (AITC), a major component of ITCs with high volatility, was therefore extracted using different methods and tested as a fumigant against four major pest species of stored products, maize weevil Sitophilus zeamais (Motsch.), lesser grain borer Rhizopertha dominica (F.), Tribolium ferrugineum (F.) and book louse Liposcelis entomophila (Enderlein). RESULTS: Whereas there was no significant difference between hydrodistillation and supercritical carbon dioxide fluid extraction in extraction rate for AITC from A. rusticana, both methods resulted in higher extraction efficiency than water extraction. AITC fumigation showed strong toxicity to the four species of stored‐product pests. Adult mortality of 100% of all four pest species, recorded after 72 h exposure to AITC fumes at an atmospheric concentration of 3 µg mL^?1, showed no significant difference from that of insects exposed to phosphine at 5 µg mL^?1, the recommended dose for phosphine. CONCLUSIONS: The results suggest good insecticidal efficacy of AITC against the four stored‐product pests, with non‐gaseous residuals on stored products. AITC obtained from A. rusticana may be an alternative to phosphine and methyl bromide against the four pest species. Copyright © 2009 Society of Chemical Industry     

Improved efficacy of ethyl formate against stored grain insects by combination with carbon dioxide in a 'dynamic' application

Ethyl formate is being evaluated as a fumigant for stored grain as it is a potential alternative to the ozone-depleting fumigant methyl bromide and to phosphine, which is under pressure owing to the development of strong resistance in stored grain insects. However, use of ethyl formate faces significant challenges, such as poor penetration through grain, significant losses to grain sorption, high concentrations of fumigant required to control insects, and flammability risks, which have limited its further development. In this study it was found that the combination of carbon dioxide (5-20%) with ethyl formate significantly enhanced efficacy of the fumigant against external living stages of the rice weevil, Sitophilus oryzae (L.), the lesser grain borer, Rhyzopertha dominica F., and the flour beetle, Tribolium castaneum (Herbst). Dynamic application of ethyl formate and carbon dioxide mixture (100 mg litre-1 ethyl formate, 20% CO2) pumped through a model silo containing wheat (50 kg) for one gas exchange was also investigated. A flow rate of 6 litres min-1 gave a relatively even distribution of fumigant throughout the grain column and similar mortality levels among cultures of S. oryzae and T. castaneum placed at three positions, the top, middle and bottom of the column. Mortality of 99.8% of mixed stage cultures of T. castaneum and 95.1% of S. oryzae was achieved in 3 h exposures to 111 and 185 mg ethyl formate h litre-1 respectively applied by the dynamic method. It is concluded that the combination of carbon dioxide with ethyl formate and dynamic application enhances distribution and efficacy of the fumigant against stored grain insects.     

雷公藤总生物碱对玉米象和赤拟谷盗的种群抑制作用

采用室内生测法研究了雷公藤总生物碱对玉米象和赤拟谷盗的种群抑制作用。结果表明,雷公藤总生物碱能显著抑制两种贮粮害虫种群的增长。雷公藤总生物碱浓度大于500mg/kg,33d时玉米象成虫死亡率高于90.83%,67d时混药饲喂的下一代（F1代）,其种群抑制率在96.70%以上;其中500mg/kg处理组存活成虫在未混药饲喂条件下,其F1代种群抑制率达80.10%。雷公藤总生物碱浓度在100-1000mg/kg范围内,对赤拟谷盗成虫无明显的致死效应,但可显著抑制其种群的增殖。当处理浓度为250mg/kg时,对赤拟谷盗的种群抑制率为54.94%;处理浓度升至500mg/kg时,种群抑制率高达98.02%。     

Bioactivity of short-chain aliphatic ketones against adults of the granary weevil, Sitophilus granarius (L.)

BACKGROUND: The granary weevil, Sitophilus granarius (L.), is one of the most damaging pests of stored grains, causing severe quantitative and qualitative losses. Sustainable control means, alternative to the commonly used fumigants and broad‐spectrum contact insecticides, are urgently needed owing to legislative limits, the development of resistant insect strains and increasing consumer demand for safe food. Short‐chain aliphatic ketones, known to be emitted by cereal grains and previously identified as repellents to adult granary weevils, were evaluated for their ability to disrupt insect orientation towards wheat grains and as possible natural fumigants. RESULTS: In behavioural bioassays, 2‐pentanone, 2‐hexanone, 2‐heptanone and 2,3‐butanedione significantly reduced insect orientation towards odours of wheat grains, with 2‐hexanone and 2‐heptanone being the most active. In fumigation tests, all compounds were effective in killing weevil adults, but they performed differently according to chemical structure, speed of action and presence of wheat grains. In the presence of grains, the highest fumigant toxicity was shown by 2‐pentanone (LC₅₀ = 8.4 ± 1.0 mg L^?1) after 24 h exposure, and by 2‐pentanone (LC₅₀ = 4.5 ± 0.3 mg L^?1), 2‐heptanone (LC₅₀ = 7.1 ± 0.3 mg L^?1) and 2‐hexanone (LC₅₀ = 8.1 ± 0.6 mg L^?1) 1 week after the treatment end. CONCLUSION: Short‐chain aliphatic ketones have potential for applications in IPM programmes for the granary weevil because of their behaviour‐altering activity and fumigant toxicity. Copyright © 2011 Society of Chemical Industry     

Effect of chitin-synthesis inhibitors on stored-product beetles

The fecundity of four important coleopteran stored-grain pests, Rhyzopertha dominica (Fab.), Sitophilus oryzae (L.), Oryzaephilus surinamensis (L.) and Tribolium castaneum (Herbst.) was assessed after exposure to wheat treated with five benzoylphenyl ureas (BPUs), members of the chitin-synthesis inhibitor group of insect growth regulators (IGRs). Chlorfluazuron was found to control all four species more effectively than triflumuron, teflubenzuron, flufenoxuron or diflubenzuron. Two weeks of exposure of parents to 0.5 mg kg ?1 of all the BPUs, except diflubenzuron, inhibited almost all F1 production and all the F2 production of each species. The fecundities of T. castaneum and O. surinamensis recovered almost to their untreated levels after two weeks of exposure to 1 mg kg ?1 of BPUs followed by two weeks on untreated wheat, but the effect of the exposure persisted for at least two weeks on untreated wheat in adult S. oryzae and to a lesser extent in R. dominica. The mean F1 response of the four species after two weeks of exposure to four doses showed clearly that the four newer BPUs were all similar in their overall effectiveness and significantly more effective than diflubenzuron, although diflubenzuron was equally effective against S. oryzae. At 0.1 mg kg ?1 triflumuron was less effective against O. surinamensis, while teflubenzuron and flufenoxuron were not very effective against the rice weevil, S. oryzae. Chlorfluazuron provided the most effective control of all four stored-product pest species, including the weevil, S. oryzae. The BPUs show particular potential for use in the stored-product industry because low dosages will effectively control the rice weevil in addition to the other major pest species.     

近10年农作物主要病虫害发生危害情况的统计和分析

2006-2015年,我国农作物病虫草鼠害总体处于严重发生状态,各类病虫害年发生面积在4.603 5亿~5.075 3亿hm2次,年均挽回粮食损失9 684.68万t,占全国粮食总产的17.35%;年均实际损失粮食1 965.49万t,占全国粮食总产的3.53%。五大粮食作物中每年通过防治挽回损失的比例,水稻、小麦、玉米、大豆和马铃薯分别占55.18%、21.29%、18.97%、1.88%和2.68%,实际造成损失的比例分别占33.67%、23.31%、35.13%、2.11%和5.79%。影响全国粮食生产最为重要的10种(类)病虫害依次为稻飞虱、水稻纹枯病、稻纵卷叶螟、玉米螟、小麦蚜虫、二化螟、稻瘟病、小麦纹枯病、小麦赤霉病、小麦白粉病;某一个病虫暴发危害时最高可实际造成200万t以上的粮食损失,总损失可达2 200万t,占某类粮食总产的12%左右,对国家粮食安全影响巨大。最具暴发和流行危害特点的种类主要有稻飞虱、稻纵卷叶螟、稻瘟病、小麦条锈病、小麦赤霉病和黏虫等6种。本文运用大量翔实的历史数据统计分析了近10年来水稻、小麦、玉米三大粮食作物病虫害的危害损失和暴发危害情况。     

Efficacy of grain protectants against four psocid species on maize,rice and wheat

BACKGROUND: Psocids are emerging pests in stored products, particularly in amylaceous commodities such as grains. Currently, their control is based on the use of fumigants and contact insecticides; however, newer data indicate that psocids are tolerant to insecticides used to control other stored‐grain species. This study evaluated the insecticides registered in the USA for use on stored maize, rice and wheat for control of the psocid species Lepinotus reticulatus, Liposcelis entomophila, L. bostrychophila and L. paeta. Mortality of exposed adult females was recorded after 7 and 14 days of exposure, while progeny production was assessed after 30 days of exposure. RESULTS: On wheat and rice, chlorpyriphos‐methyl + deltamethrin was generally more effective against exposed parental adults than spinosad or pyrethrin, while pirimiphos‐methyl was more effective on maize than spinosad or pyrethrin. In most cases, progeny production was suppressed in the treated grains. Progeny production was consistently lowest on wheat and rice treated with chlorpyriphos‐methyl + deltamethrin and maize treated with pirimiphos‐methyl. CONCLUSIONS: Chlorpyriphos‐methyl + deltamethrin and pirimiphos‐methyl were the most effective insecticides for all species and commodities. Conversely, efficacy of spinosad or pyrethrum was highly dependent on the psocid species and commodity. Published in 2009 by John Wiley & Sons, Ltd.