柠檬精油对谷蠹的生物活性

[目的]植物精油可以克服仓储害虫化学防治的种种弊端。[方法]以谷蠹为试虫,研究了不同剂量柠檬精油对谷蠹的室内生物活性。[结果]柠檬精油100μL/L处理对谷蠹成虫不仅具有较强的熏蒸活性和驱避活性,而且对其幼虫的羽化有一定的抑制作用。[结论]室内生物活性测定结果表明柠檬精油有望开发成一种绿色无污染的仓储害虫杀虫剂。     

草原蝗虫防治药剂的室内筛选

[目的]蝗虫对草原危害很严重,多年的化学防治对常规药剂产生了抗性,寻找高效低毒药剂很有必要。[方法]以氯虫苯甲酰胺等11种杀虫剂为材料,采用浸渍叶片法对华北雏蝗和宽须蚁蝗3龄若虫进行了室内毒力测定。[结果]丁虫腈、氯虫苯甲酰胺、甲维盐、氟虫腈对华北雏蝗和宽须蚁蝗均表现出较强毒力,氟虫腈对华北雏蝗的毒力最高(LC50值为0.14 mg/L),毒死蜱对华北雏蝗的毒力最低(LC50值为12.31 mg/L),丁虫腈对宽须蚁蝗的毒力最高(LC50值为0.11 mg/L),毒死蜱对宽须蚁蝗的毒力最低(LC50值为13.99 mg/L)。[结论]11种药剂对华北雏蝗和宽须蚁蝗毒力的差异,可用于防治以上2种蝗虫高效低毒药剂的筛选。     

复配茶树精油对6种仓储害虫成虫的熏蒸活性研究

为了筛选低毒高效的植物杀虫剂,在28℃条件下,研究了复配茶树精油对锯谷盗、谷蠹、赤拟谷盗、麦蛾、印度谷螟、嗜卷书虱6种仓储害虫的熏蒸作用。结果表明,熏蒸48 h后,复配茶树精油对6种仓储害虫成虫均有一定的熏蒸活性,其中对嗜卷书虱的熏蒸效果显著,其LC_(50)值为96.38μL/L,其次为麦蛾和印度谷螟,锯谷盗、谷蠹、赤拟谷盗对复配茶树精油的敏感性低。     

黄皮种子甲醇提取物对米象的生物活性

[目的]目前全世界对储粮害虫的防治方法主要采用化学杀虫剂,但由于化学药剂的3R问题,开发环境友好的植物性杀虫剂成为迫切需要。试验采用冷浸法对黄皮种子中的生物活性物质进行提取;并以仓储害虫米象为试验对象,采用饲料拌药法对黄皮种子甲醇提取物触杀活性进行了测定。[结果]黄皮种子提取物对米象具有一定的触杀活性,在处理7、10、14 d后对米象的LC50值分别为879.37、324.53、245.31 mg/kg。各萃取相中石油醚相的活性最高,在处理7、10、14 d后,对米象的LC50值分别为383.85、254.11、154.13 mg/kg。[结论]黄皮种子甲醇提取物对米象有很好的触杀活性。     

几种杀虫剂对4种鳞翅目食叶害虫的毒力和模拟田间防效

[目的]明确对4种鳞翅目食叶害虫具有较好毒杀作用的药剂。[方法]用人工饲料混药法和浸虫浸叶法测定了几种杀虫剂对4种害虫的室内毒力,并模拟大田进行了药效试验。[结果]处理48 h,2%甲氨基阿维菌素苯甲酸盐SL对甜菜夜蛾、棉铃虫和斜纹夜蛾3龄幼虫的毒力均最高,LD50值分别为8.235、0.236、0.267滋g/g;10%高效氯氟氰菊酯EW对黏虫的毒力作用明显,LC50值达13.954 mg/L。模拟田间药效中2%甲氨基阿维菌素苯甲酸盐SL 1 500倍液和10%高效氯氟氰菊酯EW 3 600倍液的1颐1混剂效果最好,校正防效达99.39%。[结论]其结果可为筛选4种鳞翅目食叶害虫的理想防治药剂提供参考。     

二点委夜蛾高效低毒防治药剂室内毒力评价

[目的]二点委夜蛾是我国耕作制度变革后新发生的暴发性害虫,生产上急需筛选出对其高效的药剂。[方法]采用浸虫法测定了10种杀虫剂对二点委夜蛾幼虫的室内毒力。[结果]供试药剂对试虫的毒力差异较大。甲维盐、高效氯氰菊酯和辛硫磷对试虫的毒力最高,氰戊菊酯等5种杀虫剂对试虫也具有较高毒力,其LC50值介于30-100 mg/L;而二嗪磷和阿维菌素对试虫的毒力较低。[结论]在生产上,应科学合理使用现有各类杀虫药剂,并应进一步开展其以生物学、生态学研究为基础的综合防治技术研究。     

2.5％功夫乳油防治荔技蝽象

荔枝蝽象(Tessaratoma papillosa Drury)是我省荔枝、龙眼上的主要害虫,其成虫、若虫刺吸荔枝、龙眼的幼芽、嫩梢、花、果的汁液,同时放射臭液使嫩叶、花蕊及果实有灼伤状,变黄褐色,造成落花、落果、叶片枯萎,对产量影响很大。1999年我所选用英国捷利康公司生产的2.5％功夫乳油进行防治荔枝蝽象药效试验,现将试验结果小结如下：     

杀虫剂对脊胸露尾甲生物活性的测定方法筛选

[目的]为筛选出对澳洲坚果新害虫——脊胸露尾甲成虫和幼虫灵敏的生物活性测定方法。[方法]以甲氨基阿维菌素苯甲酸盐为供试药剂,分别采用浸虫法、饲喂法和药膜法开展了生物活性测定试验。[结果]处理24 h后,浸虫法对成虫的生物活性最高(LC₅₀值为28.48 mg/L),显著高于药膜法(LC₅₀值为206.81 mg/L)和饲喂法(LC₅₀值为343.80 mg/L);饲喂法对2龄幼虫的生物活性最高(LC₅₀值为44.30 mg/L),显著高于药膜法(LC₅₀值为144.81 mg/L)和浸虫法(LC₅₀值为142.27 mg/L)。[结论]浸虫法可用于成虫的生物活性测定、饲喂法可用于幼虫的生物活性测定,该结论可为脊胸露尾甲成虫及幼虫的生物活性测定方法的选择提供参考。     

有机农药防治杏园害虫试验

为了给有机杏园害虫防治提供理论依据,选取2种有机农药在杏园内进行了防治黄斑长翅卷叶蛾和桃粉大尾蚜的药效试验,并分别测定其室内毒力.结果表明:制剂用量0.6%氧苦·内酯AS 12 mg/L和5%天然除虫菊素EC 100 mg/L防治桃粉大尾蚜效果均较好,施药后7 d的校正防效分别为99%和100%;0.6%氧苦·内酯AS 12 mg/L防治黄斑长翅卷叶蛾幼虫药后7 d防效达到93.75%,明显好于5%天然除虫菊素EC 100 mg/L.采用夹毒叶片法测定了0.6%氧苦·内酯As和5%天然除虫菊素EC对黄斑长翅卷叶蛾幼虫的毒力,其LC50值分别为5.7886、80.6836 mg/L;浸渍法测定了0.6%氧苦·内酯AS和5%天然除虫菊素EC对桃粉大尾蚜的毒力,其LC50值分别为9.5384、33.6851 mg/L.在实际应用中建议使用0.6%氧苦·内酯As进行防治.     

7种农药对瓜蚜的室内毒力测定

[目的]采用浸叶法测定7种药剂对瓜蚜的毒力.[结果]结果表明:阿维菌素活性最高,LC50值为8.2728 mg/L,其次为甲氨基阿维菌素苯甲酸盐,LC50值为23.2278 mg/L,啶虫脒的LC50值为29.2927 mg/L,吡虫啉和毒死蜱的敏感性最低,LC50值分别为46.0487、48.9797 mg/L.螺虫乙酯各测试质量浓度处理后48、72 h时的平均死亡率仅为8.9％、11.2％,高效氯氰菊酯测试质量浓度达2000mg/L时,24 h校正死亡率仅为37.97％.[结论]7种药剂对瓜蚜的毒力排序为阿维菌素＞甲氨基阿维菌素苯甲酸盐＞啶虫脒＞吡虫啉＞毒死蜱＞高效氯氰菊酯＞螺虫乙酯.     

防治稻水象甲成虫药剂室内筛选

[目的]2010年在贵州首次发现检疫性害虫稻水象甲(Lissorhoptrus oryzophilus Kusche1),为了快速筛选出高效、低毒化学药剂,为贵州省稻水象甲成虫化学防治提供依据,采集田间稻水象甲成虫进行室内药剂生测筛选试验。[结果]48%毒死蜱EC对稻水象甲成虫防效最好,药后1 d各剂量处理防效在77%以上,药后3 d各剂量处理防效均达100%;其次为40%氯虫苯甲酰胺.噻虫嗪WG,药后1 d各剂量处理防效在72%以上,药后3 d各剂量处理防效在87%以上;10%醚菊酯SC在剂量为150、180 g a.i./hm2时,对稻水象甲成虫均有较好的防治效果。[结论]以上3种药剂防治稻水象甲成虫活性高且速效性好,可作为防治稻水象甲成虫的选择药剂。     

Efficient Sex Pheromone Trapping: Catching The Sweetpotato Weevil, Cylas formicarius

The sweetpotato weevil, Cylas formicarius (Fabricius) (Coleoptera: Brentidae), is the most serious pest of sweetpotato around the world, damaging sweetpotatoes in the field and in storage, as well as being a quarantine pest. Because the larval period is spent within vines or tubers, and the adults are nocturnal, chemical control frequently is not effective. In addition, there are few natural enemies, and pheromone-based trapping does not appear to reduce the damage level. In the present study, we evaluated a number of parameters that affect pheromone-based trap catch, including trap design, trap size, trap color, and height at which the traps are placed. Pherocon unitraps caught higher numbers than ground, funnel water, or delta traps. Medium-sized traps (13?×?17.5 cm) were more effective than larger or smaller traps. In a color-choice test, C. formicarius preferred red over gray, brown, blue, white, yellow, black, or red traps; light red was more attractive than other shades of red. Maximum catches were obtained when the traps were set 50 cm above the crop canopy. Light-red unitraps with pheromone lures caught more adults than identical traps without lures, suggesting that C. formicarius is influenced by both visual and olfactory cues. Pheromone-baited light-red unitraps, 13?×?17.5 cm, installed 50 cm above the crop canopy, were the most effective at catching C. formicarius adults, and they appear to have the greatest potential for use in trap-and-kill strategies and eradication programs.     

Response of the Egg Parasitoids <Emphasis Type="Italic">Trissolcus basalis</Emphasis> and <Emphasis Type="Italic">Telenomus podisi</Emphasis> to Compounds from Defensive Secretions of Stink Bugs

We tested the hypotheses that host-searching behavior of the egg parasitoids Telenomus podisi and Trissolcus basalis may be differentially influenced by the different blends of volatiles released from the metathoracic glands of adult stink bug host species. We further studied whether such a differential response is due to different individual components of these glands and whether these responses reflect host preferences. Y-tube olfactometer bioassays were carried out with crude extracts of metathoracic glands of five different host species of neotropical stink bugs. Additionally, we tested the parasitoids’ responses to synthetic standards of individual compounds identified in these stink bug glands. Results showed that females of T. basalis and T. podisi responded differentially to crude gland extracts of the different species of host stink bugs and to the compounds tested. The parasitoid T. basalis showed a positive taxic behavior to Nezara viridula methathoracxic gland extracts of a host species preferred in the field, i.e., N. viridula. Furthermore, T. basalis responded positively to 4-oxo-(E)-2-hexenal and (E)-2-decenal, two components of N. viridula glandular secretion. Higher residence time, reduced linear velocity, and higher tortuosity in the arm of the olfactometer supplied with 4-oxo-(E)-2-hexenal showed that this compound modifies the kinetics of some traits of T. basalis walking pattern and suggests that it might stimulate the searching behavior of this parasitoid. The parasitoid T. podisi was attracted to crude gland extracts of the preferred host (Euschistus heros) and also to 4-oxo-(E)-2-hexenal. Additionally, this parasitoid responded positively to (E)-2-hexenal and to the hydrocarbon tridecane, both of which are defensive compounds released from the metathoracic glands by several stink bugs. The results indicate some degree of specialization in the response of two generalist parasitoid species toward defensive secretions of stink bugs.     

Male-Produced Aggregation Pheromone of Coffee Bean Weevil, <Emphasis Type="Italic">Araecerus fasciculatus</Emphasis>

The coffee bean weevil (CBW), Araecerus fasciculatus (De Geer, 1775), is a cosmopolitan stored-product pest, especially in tropical and subtropical areas. Previous reports showed evidence for aggregation behavior of CBW and this study aimed to identify and evaluate the aggregation pheromone of this pest. Whole-body solvent extractions were analyzed by coupled gas chromatography-mass spectrometry and comparison of male and female extracts showed a male-specific compound which was identified as squalene, 2,6,10,15,19,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene. This compound was shown to attract male and female CBW in Y-tube olfactometer and storage trap assays. The longevity of septum lures was also evaluated in a warehouse. Squalene could be useful in monitoring and controlling this pest.     

黄花蒿提取物的杀虫活性

黄花蒿精油对米象、玉米象、绿豆象和蚕豆象等４种仓库害虫具有很强的熏杀活性,其甲醇和乙醇提取物对小菜蛾、菜青虫、大菜粉蝶、银纹夜蛾和斜纹夜娥幼虫也具有一定的杀虫活性。     

Behavioral Responses of Adult <Emphasis Type="Italic">Sitophilus granarius</Emphasis> to Individual Cereal Volatiles

The antennae of Sitophilus granarius (L.) (Coleoptera: Curculionidae) adults detect a wide variety of compounds in the odor blend of various cereal grains (Germinara et al., Tec. Molit., 53:27–34, 2002). In the present study, we looked at the behavioral responses of the granary weevil to 20 of these individual volatiles (aliphatic alcohols, aldehydes, ketones, and aromatics) in a two-choice pitfall olfactometer, using the aggregation pheromone and propionic acid as the attractant and repellent controls, respectively. Five doses, ranging from 1 μg to 1 mg, of each compound were tested. At least one concentration of eight compounds attracted beetles but required doses 1,000- to 5,000-fold higher than the concentration of aggregation pheromone to elicit a response. Three compounds, while attractive at lower concentrations, acted as repellents at higher doses. Twelve compounds were repellent at concentrations similar to the quantity of propionic acid that significantly repelled beetles. The data show that granary weevil adults have the ability to respond behaviorally to a wide range of cereal volatiles and that responses may change as a function of concentration. The results suggest that host finding behavior of weevils will depend on the balance of positive and negative volatile stimuli from grain as the relative concentrations of volatiles may change during storage. An understanding of how the weevils respond to such changes could be useful for the development of effective integrated pest management strategies.     

增效成分对桐酸酯用于仓贮害虫防治时的协效作用

中日合作研究了增效成分对桐酸酯类系列品种对玉米象的防治效果。试验表明含增效成分的桐酸酯对玉米象具有明显的致死效果，致死率为70％～87．5％，未添加增效成分的处理致死率只有2．5％～5％。不含增效成分的桐酸酯处理玉米象的平均产卵数是含增效成分处理的2～3倍，含增效成分的桐酸酯具有明显抑制害虫产卵的作用，对卵的羽化具有完全的抑制作用。     

Chemicals Used for Host Recognition by the Granary Weevil Parasitoid Lariophagus distinguendus

In order to develop methods for mass rearing of the parasitic wasp Lariophagus distinguendus, we characterized and identified chemicals used by this parasitoid to recognize wheat grains infested by its host, larvae of the granary weevil, Sitophilus granarius, a major pest of stored grain worldwide. Bioassays revealed that drumming and drilling behavior of the parasitoids on grain models of filter paper treated with host feces was as intense as on host-infested grains. Thus, chemicals from feces are highly important to recognize infested grains. Extracts of the feces with hexane or dichloromethane applied on grain models were able to provoke drumming and drilling activity. Hexane extract of feces was as active as infested grain itself. Subsequent fractionation of the hexane extract by adsorption chromatography revealed that highest activity was recovered in the dichloromethane fraction. This fraction was characterized by the presence of -tocopherol, -tocopherol, -tocotrienol, cholesterol, ergostenol, and -sitosterol. Synthetic chemicals in proportions found in the active dichloromethane fraction stimulated drumming behavior in bioassays. The significance of these results with respect to the mass propagation of L. distinguendus as natural enemies for the control of the granary weevil is discussed.     

EFFECT OF REARING CONDITIONS ON PRODUCTION OF STERNAL GLAND SECRETION,AND IDENTIFICATION OF MINOR COMPONENTS IN THE STERNAL GLAND SECRETION OF THE PREDATORY STINK BUG <Emphasis Type="Italic">Eocanthecona furcellata</Emphasis>

Production of the male specific compound, 6,10,13-trimethyltetra- decyl isovalerate by the predatory stink bug Eocanthecona furcellata (Wolff) was dramatically affected by rearing conditions. Male bugs kept isolated after eclosion produced an average of 1,948 ng of 6,10,13-trimethyltetradecyl isovalerate per bug, whereas male bugs reared in groups of 5–8 bugs produced an average of only 4 ng of 6,10,13-trimethyltetradecyl isovalerate per bug. Same-sex or mixed-sex pairs of bugs produced less than 50 ng per bug. Male bugs kept isolated for 1~wk and then grouped for 1~wk produced 3 ng of 6,10,13-trimethyltetradecyl isovalerate per bug, whereas male bugs grouped first and then isolated produced 135 ng of 6,10,13-trimethyltetradecyl isovalerate. A total of 11 minor components in relative amounts of less than 1% of the major 6,10,13-trimethyltetradecyl isovalerate were found in the sternal gland secretion. These included 6,10,13-trimethyltetradecanol, acetate, propionate, and butyrate esters of 6,10,13-trimethyltetradecanol, and isovalerate or valerate esters of homologs of 6,10,13-trimethyltetradecanol.