红火蚁工蚁对颜色信号的选择与利用

为探明红火蚁Solenopsis invicta工蚁对颜色信号的选择与利用,本研究测定了不同颜色色卡对工蚁的趋向行为以及不同颜色饵料对工蚁觅食行为的影响,以期为红火蚁的高效监测与防控提供重要基础。结果表明颜色显著影响了红火蚁工蚁的趋向行为,黑色对工蚁的引诱率最高,可达32%;黄色对工蚁的引诱率最低,仅为7%。研究也发现不同颜色的饵料显著影响了红火蚁工蚁的觅食。在5 min时间内,工蚁在黄色、绿色以及蓝色饵料上觅食的数量最多,显著高于在紫色和黑色上饵料的觅食工蚁数;工蚁对红色、橙色、黄色、绿色、蓝色饵料的搬运量最大,显著高于紫色与黑色的饵料。综上,红火蚁工蚁可以识别与利用颜色信号,在制备红火蚁监测与防控饵剂时,可以考虑将饵剂染色红、橙、黄、绿、蓝等反射波长较长的颜色,以便工蚁能快速定位到饵剂并搬运更多的饵剂到蚁巢中。     

Significance of digging behavior to mortality of red imported fire ant workers, Solenopsis invicta, in fipronil-treated sand

The effect of fipronil-treated sand on digging behavior and mortality of red imported fire ant, Solenopsis invicta Buren, workers was examined in the laboratory. No-choice digging bioassays where fipronil-treated sand was the only available digging substrate were conducted on two colonies at fipronil concentrations of 0.00, 0.05, 0.10, 0.50, 1.00, 1.50, and 2.00 ppm. Workers dug into the fipronil-treated sand in all cases, even at 2.0 ppm level, which caused 100% mortality in acute toxicity tests for both colonies. At 1.5 and 2.0 ppm, workers from the less sensitive colony had significantly higher mortality than those from the more sensitive colony, which might be explained by the significantly higher digging activity of the less sensitive colony. In two-choice digging bioassays where untreated sand was also available, workers dug into the fipronil-treated sand in 29 of 30 cases, even at 10.0 ppm level. At 1.0 and 10.0 ppm, mortality was positively correlated to digging effort in treated sand; however, such correlation was significant only at 1.0 ppm level. This indicates that digging did affect mortality; however, such effect is concentration dependent.     

电场对红火蚁工蚁聚集的影响

为了研究电刺激对红火蚁聚集的影响,本研究通过改变电压、电线裸露程度及电线间距,测定了在不同电场强度下红火蚁工蚁的聚集程度和行为反应。结果表明在不同电压(1.5 V、3 V、6 V)、两根裸露电线不同间距(2 mm、4 mm)条件下,电压6 V、电线间距为2 mm时对红火蚁的吸引效果最强,电线上聚集工蚁最多达59.2头;强电场(电压36 V,电线间距分别为2 mm、4 mm)条件下,电压36 V、电线间距2 mm时电线上聚集工蚁最多达75头;另外,电线裸露程度也显著影响电场对红火蚁的吸引作用。在模拟设备电压(36 V)条件下红火蚁接受电刺激后产生明显的行为反应,表现为身体不断颤抖,在电线周围继续寻找电刺激。     

几种饵料对红火蚁觅食的引诱作用

在荒地类型生境中测定花生酱、猫饲料、狗饲料、花生油、面包及蜂蜜等几种常见饵料对红火蚁的引诱作用。结果表明:面包、狗饲料、猫饲料和花生酱对红火蚁引诱力较强,花生油次之,蜂蜜最低;选择性试验结果表明红火蚁对供试的几种饵料无明显选择性。     

Effect of soil humidity on the survival of Solenopsis invicta Buren workers

The effect of soil humidity on the survival of Solenopsis invicta (Buren) workers was evaluated in this study. The study showed that the relative soil water (RSW) content inside the mound contained less variation than the surrounding soil. At a depth of 5 cm underground, the RSW was 7.6% in the mound, while it was 29% in the surrounding soil. At a depth of 20 cm underground, the RSW was 99% in the surrounding soil, while in the mound, the RSW did not reach 98% until it was 45-cm deep. The soil humidity affected the survival rate of S. invicta. For workers, the survival rate decreased when they were exposed to a higher RSW. The spring population had a higher tolerance to a high RSW than the autumn population, while the drought tolerance was the opposite. In extreme RSW, the longer that S. invicta was exposed, the lower their survival rate. The drought tolerance of the fire ant workers could be improved if they were pre-exposed to a low non-lethal RSW for a short period of time. The water content of the workers changed after acclimation to humidity. After a low RSW treatment, the water content of the acclimated workers was higher than the control workers. This suggests that this species is able to maintain a certain water content after acclimation, and that the water content of workers increases in accordance with the RSW.     

红火蚁不同品级个体的药剂敏感性研究

【目的】红火蚁Solenopsis invicta Buren不同品级的个体在群体生存中担负不同的功能。然而,红火蚁群体中不同品级个体的药剂敏感性还不清楚。【方法】本文采用点滴法测定了氟虫腈、高效氯氰菊酯和茚虫威三类不同药剂对红火蚁各品级个体的触杀毒力,以了解其药剂敏感性。【结果】研究结果显示,红火蚁对不同药剂的敏感性存在显著差异,对氟虫腈最为敏感,高效氯氰菊酯次之,而对茚虫威的敏感性最低,但不同品级个体的药剂敏感性规律却基本一致。有翅雌蚁、有翅雄蚁和蚁后的药剂敏感性最高,3个品级个体的药剂敏感性没有显著差异;除高效氯氰菊酯外,兵蚁的敏感性显著低于有翅蚁和蚁后,而工蚁又显著低于兵蚁。4龄幼蚁对供试的3种杀虫剂的敏感性非常低,致死中量分别为428.77 mg/kg、699.77 mg/kg和1 159.95 mg/kg,比对有翅雌蚁的致死中量高数百至数千倍。对毒力线斜率值的分析发现,同一品级内个体间对不同药剂的敏感性也存在显著差异,对氟虫腈的敏感性表现出品级内个体较大差异,特别是兵蚁和工蚁的敏感性差异最大,其斜率值分别为1.1和1.8,而对茚虫威的个体敏感性差异极小,其斜率值均≥4.7,且工蚁个体间表现出最高的同质性,其斜率值达7.8。【结论】同一品级的个体对不同药剂的敏感性差异没有一致规律,但基本上表现出个体差异较小的特点,特别是4龄幼蚁、有翅雄蚁和蚁后3个品级内个体的药剂敏感性差异较小,其斜率值均≥4.0。本研究的结果为田间防治红火蚁化学药剂的合理使用提供理论指导。     

诱饵诱集时间与红火蚁工蚁诱集量的关系研究

为了明确诱饵诱集时间与红火蚁工蚁诱集量之间的关系,确定最佳的诱饵放置时间,本研究采用火腿肠诱饵诱集法,观察不同季节、不同时间段红火蚁诱集的个体数量,利用房室模型分析诱饵诱集时间与红火蚁工蚁诱集量之间的关系。结果表明,随着诱饵放置时间的增加,红火蚁工蚁的诱集数量会出现一个高峰,春季诱集高峰出现在诱饵放置后38-44 min,秋季出现在诱饵放置后24-29 min,并建立了不同季节、不同时间段红火蚁诱集量与时间的关系模型,分别为Y=12764.8807×e(-0.029102 X)"12820.4625×e(-0.030064 X)(春季上午)、Y=16166.6800×e(-0.023994 X)"16217.0808×e(-0.024866 X)(春季下午)、Y=12211.9095×e(-0.040576 X)"12275.2496×e(-0.041620 X)(秋季上午)、Y=12306.4111×e(-0.049724 X)"12383.6907×e(-0.051217 X)(秋季下午)。因此,在利用火腿肠诱饵监测红火蚁时,春季诱饵放置的最适时间约为40 min,秋季的最适时间约为30 min。     

甘氨酸和赤藓糖醇胶饵对红火蚁工蚁的毒杀效果

前期研究发现甘氨酸和赤藓糖醇对红火蚁Solenopsis invicta Buren有较好的毒杀效果,为进一步挖掘这两种物质的实际应用价值,在室内测试了甘氨酸和赤藓糖醇不同浓度配比的水溶液及胶状饵剂对红火蚁工蚁的毒杀效果.结果显示,20％的配比为1∶3、3∶1的赤藓糖醇和甘氨酸溶液喂饲48 h红火蚁工蚁的死亡率分别为8...     

呋虫胺对红火蚁工蚁的毒杀活性及行为影响

本文研究呋虫胺对红火蚁Solenopsis invicta Buren中型工蚁的毒杀活性及爬杆能力、抓附能力、行走能力、攻击能力等行为影响。以水试管喂毒法对红火蚁进行试验。结果表明,1 mg/L和5 mg/L呋虫胺处理13 h后,红火蚁中型工蚁校正死亡率分别为55.56%、97.78%,0 mg/L、1 mg/L和5 mg/L呋虫胺处理9 h后,红火蚁中型工蚁爬杆率分别为100.00%、45.56%和7.78%,抓附率分别为100.00%、33.33%和15.56%,行走率为100.00%、42.22%和25.56%,攻击率为100.00%、36.67%和0.00%。呋虫胺对红火蚁中型工蚁具有良好毒杀活性和行为影响,在红火蚁防控上具有良好应用前景。     

Diet-induced nonmelanized cuticle in workers of the imported fire ant Solenopsis invicta buren

Nonmelanized cuticle development was induced in workers of Solenopsis invicta by feeding them an insect-free diet. The nonmelanized workers weighed less and had smaller mean headwidths than workers from normal colonies. Although nonmelanized ant colonies appeared to function normally in the laboratory, their attempts at stinging were felt only as “pin pricks.” Chemical analysis of venom alkaloids and cuticular hydrocarbons indicated no qualitative differences between nonmelanized and normal workers. Tyrosine, an essential amino acid tanning precursor, was found in adequate quantities in the free amino acid pool of nonmelanized ants. The specific cause of the nonmelanized condition is not known.     

红火蚁防治区农药残留动态规律研究

【目的】红火蚁Solenopsis invicta目前的主要防治方法为化学防治,了解红火蚁防治常用的药剂在绿地环境中的残留动态将有助于我们合理使用药剂。【方法】应用气相色谱建立了红火蚁常用药剂残留的测定方法,并测定了不同施用类型药剂防治草坪上的红火蚁种群后,药剂在土壤和草样中的残留动态。【结果】结果表明4.5%高效氯氰菊酯乳油2 000倍液在土壤中的原始沉积量分别是1.903 mg/kg,草坪草上的沉积量为7.806 mg/kg。在土壤中的半衰期为6.31 d,在草样中的半衰期为4.86 d。0.096%氟虫腈粉剂30 g/巢在土壤中的原始沉积量分别是0.073 mg/kg,草坪草上的沉积量为0.135 mg/kg;在土壤中的半衰期为5.57 d,在草样中的半衰期为2.96 d。0.015%多杀菌素35 g/巢施用后,未检测出土壤中有多杀菌素的残留。【结论】残留测定结果表明高效氯氰菊酯乳油和0.096%氟虫腈粉剂在施用后,一段时间内会在草坪上有残留,从而导致对草坪上的非靶标节肢动物造成伤害,而施用0.015%多杀菌素饵剂则不会对节肢动物群落产生较大的影响。     

Infection characteristics of Solenopsis invicta virus 2 in the red imported fire ant, Solenopsis invicta

Solenopsis invicta virus 2 (SINV-2) is the second virus identified from the fire ant, S. invicta Buren. SINV-2 is unique among positive-strand RNA viruses from insects by possessing four cistrons in a monopartite genome. Fire ant colonies testing positive for SINV-2 by RT-PCR did not exhibit any discernable symptoms. RT-PCR-based surveys for SINV-2 among 688 fire ant mounds in Alachua County, Florida, sampled during the period January, 2006 through December, 2007 showed that the prevalence of SINV-2 among nests ranged from 1.6% to 16.4%. Unlike S. invicta virus 1, no seasonal-associated prevalence was observed with regard to SINV-2 infection among fire ant colonies. No social form specificity was evident; SINV-2 was found in both monogyne and polygyne S. invicta ants. Real-time quantitative PCR experiments showed that SINV-2 genome equivalents per individual ant ranged from 1.9 × 10⁷ in. pupae to 4.3 × 10¹¹ in. inseminated queens. The SINV-2 infection was detected in all ant stages examined (eggs, larvae, pupae, workers, and queens). Tissue tropism studies indicated that the alimentary canal (specifically the midgut) is most likely the susceptible tissue. SINV-2 was successfully transmitted to uninfected S. invicta ants by feeding a partially purified homogenate of SINV-2-infected ants. The SINV-2 transmission rate ranged from 30% to 80%, and both positive (genomic) and negative (replicative) SINV-2 RNA strands accumulated in recipient ants over the course of the experiment. These results indicated that SINV-2 replicates within S. invicta.     

研究红火蚁工蚁活动性的新方法-刻度图示法

应用一种新方法--刻度图示法研究红火蚁工蚁Solenopsis invicta Buren群体活动性规律,结果表明,标尺上红火蚁最高爬升高度、平均爬升高度、工蚁恢复平静时间、工蚁累计数量均随着蚁巢体积增大而增大,通过分析建立红火蚁工蚁活动性程度各指标值与蚁巢大小关系多个模型.     

Establishing guidelines to improve identification of fire ants Solenopsis xyloni and Solenopsis invicta

As red imported fire ant, Solenopsis invicta Buren, continues to expand its range into the southwestern United States, it can be easily confused with the native southern fire ant, Solenopsis xyloni McCook. Variability in the morphological characteristics commonly used to differentiate these ant species was quantified by examining the length of the clypeal tooth, striations of the mesopleuron, length of antennal scape, area of the petiolar process, number and size of mandibular teeth, and color by using both scanning electron and light microscopy. Given enough samples, the average values of each of these characteristics is different between the two species; however, significant morphological variability occurs in both S. xyloni and S. invicta populations, creating an area of overlap where either of the two species could exhibit similar characteristics. Better differentiation of these two species is achieved using a combination of characteristics, but morphological techniques are not dependable unless numerous ants from each population are analyzed by a taxonomist familiar with Solenopsis. For situations requiring a more accurate identification, such as before quarantining a county or a portion of a county, a molecular technique using mitochondrial DNA and polymerase chain reaction techniques was developed.     

5种有机溶剂对红火蚁的毒力

红火蚁Solenopsis invicta Buren是一种重要的入侵害虫,可对农林生产、人体健康等造成严重威胁.毒饵诱杀是红火蚁防治的重要措施,高效的红火蚁毒饵有效成分需要通过胃毒测试筛选获得,而用于测试的胃毒药剂的配制则需借助对红火蚁微毒或无毒性的助溶剂.本文通过糖水饲喂法研究了不同剂量丙酮、吐温20、吐温80、二...     

研究红火蚁工蚁活动性的新方法—刻度图示法

应用一种新方法——刻度图示法研究红火蚁工蚁Solenopsis invicta Buren群体活动性规律,结果表明,标尺上红火蚁最高爬升高度、平均爬升高度、工蚁恢复平静时间、工蚁累计数量均随着蚁巢体积增大而增大,通过分析建立红火蚁工蚁活动性程度各指标值与蚁巢大小关系多个模型。     

Pathogenicity of Beauveria bassiana ANU1 to the red imported fire ant,Solenopsis invicta workers in Korea

The red imported fire ant (RIFA), Solenopsis invicta, is one of the globalized invasive pests. This study focused on pathogenicity and virulence of entomopathogenic fungi as one of the biological control agents to RIFA workers under different temperatures. The fungal pathogen, Beauveria bassiana ANU1 was isolated from Korea in 2015 and showed the pathogenicity to RIFA workers. A conidial suspension (1 × 10⁷ conidia/ml) induced a low mortality from day 2 after treatment and reached to 100% mortality at day 7 and day 8 after treatment for major and minor workers, respectively. The median lethal concentrations of B. bassiana ANU1 were calculated as 3.9 × 10³ for major and 4.6 × 10³ for minor workers at day 7 after treatment. Low temperatures decreased a virulence of B. bassiana ANU1 (1 × 10⁷ conidia/ml) to RIFA and showed mortality of 26.6% for major and 20% for minor workers. Based on bioassay results, this study provides one of possibilities of effective and successful strategy for controlling RIFA by entomopathogenic fungi.     

Metapleural- and postpharyngeal-gland secretions from workers of the ants Solenopsis invicta and S. geminata

Chemical analyses by GC-MS of the metapleural glands (MG) from workers of Solenopsis invicta and S. geminata revealed for the first time the chemical composition of these glands and showed small differences between the two species. The MG of both species contain oleic, stearic, linoleic, and palmitic acid. Both ants, in addition, have small but significant amounts of hydrocarbons in their MG reservoir, which are the same as those found in their postpharyngeal glands (PPG). The PPG of both species contain alkanes, alkenes, and Me-branched alkanes. Each species is characterized by a specific composition of PPG chemicals with some overlap between species. These results suggest that the MG synthesizes mainly palmitic, linoleic, oleic, and stearic acids in these two ants, whereas PPG contains hydrocarbon mixes that widely vary between these two phylogenetically related species.     

深圳市红火蚁婚飞规律研究

本研究利用自制红火蚁Solenopsis invicta Buren收集装置对红火蚁婚飞规律进行研究,结果表明:本试验过程中共观察到婚飞273次,无论大、中、小蚁巢均有有翅蚁婚飞现象;共收集到有翅蚁10 618头,雌雄比为2.1:1;单次婚飞有翅蚁均为雌虫的有167次,均为雄虫的有25次,单次婚飞有翅蚊既有雌虫又有雄虫(雌虫+雄虫)的共81次;同一蚁巢可以发生多次婚飞,同一蚁巢不同次婚飞的有翅蚁性别比也会发生变化;除2009年11月和2010年2月未收集到有翅蚁,其余各月均可观察到有翅蚁婚飞,婚飞最高峰期为2010年4月和5月,其次是2009年6-9月,婚飞次数和收集到的有翅蚁数量成明显的正向相关关系;8:30-15:00均有有翅蚁婚飞,而婚飞高峰期为11:30-13:30,婚飞一般持续30～150 min.婚飞一般发生在雨后晴天或相对低温后气温快速回升以后.     

福建省入侵红火蚁扩散规律研究

【目的】重大入侵害虫红火蚁Solenopsis invicta Buren广泛分布传播于世界各地,为了掌握红火蚁在新入侵地的传播和扩散的规律,对红火蚁入侵史进行溯源,以期为预防红火蚁入侵提供重要依据。【方法】本文对福建省各地入侵红火蚁的基本入侵参数进行分析,分别对入侵时间与蚁巢数量、蚁巢发生密度以及不同生境蚁巢密度进行模型拟合。【结果】结果表明,入侵方式和入侵地生境的差异导致了入侵红火蚁不同种群的发展状态。由废旧资源携带传入的入侵红火蚁种群,其发生面积较小,扩散的速率较慢,为28.1~116.4 m/年;由草皮苗木携带传入的入侵红火蚁种群,其发生面积较大,扩散的速率较快,为126.1~555.5 m/年。【结论】建立了蚁巢数量、密度与入侵时间之间的关系模型,分别为N=1 003.9Ln(t)+336.27,D=0.0966e~(0.583t),并以此推测三个入侵事件的发生时间范围。