A new fire ant (Hymenoptera: Formicidae) bait base carrier for moist conditions

BACKGROUND: A new water‐resistant fire ant bait (T‐bait; cypermethrin 0.128%) consisting of dried distillers grains with solubles (DDGS) as a carrier was developed and evaluated against a standard commercial bait (Advion^®; indoxacarb 0.045%) under both laboratory and field conditions. RESULTS: When applying the normal T‐bait or Advion^® in the laboratory, 100% of Solenopsis invicta Buren worker ants were killed within 4 days. However, when the T‐bait and Advion^® were wetted, 70.6 and 39.7% of the ants were killed respectively. Under field conditions, dry T‐bait and dry Advion^® had almost the same efficacy against ant colonies. However, when T‐bait and Advion^® came in contact with water, the former's ability to kill S. invicta colonies in the field was only marginally reduced, while Advion^® lost virtually all of its activity. In addition, DDGS was also shown to be compatible with a number of other insecticides, such as d‐allethrin, permethrin and pyrethrin. CONCLUSION: Based on its properties of remaining attractive to the fire ants when wetted, combined with its ant‐killing abilities both in the laboratory and in the field, T‐bait is an efficient fire ant bait, especially under moist conditions. Copyright © 2010 Society of Chemical Industry     

0.2%高效氯氰菊酯粉剂对田间红火蚁种群数量及蚁巢迁移的影响

为科学评价触杀性粉剂对红火蚁Solenopsis invicta Buren的防治效果,利用0.2%高效氯氰菊酯粉剂对田间红火蚁蚁巢进行单蚁巢处理,分析粉剂施用剂量和次数对田间红火蚁种群数量及蚁巢迁移的影响。结果表明,触杀性粉剂处理可在短期内显著降低红火蚁的蚁巢数量和工蚁诱集数量,50 g/巢和100 g/巢处理1 d后,蚁巢数量降幅分别达55.17%和66.04%,工蚁诱集数量降幅分别达31.79%和51.95%,但5～9 d后基本恢复至处理前水平,第21天蚁巢增加率达86.21%和37.74%,持效性较差。增多粉剂施用次数同样也只能在短期内压低红火蚁的蚁巢数量和工蚁诱集数量,施用1、2和3次粉剂1 d后蚁巢数量降幅分别达61.44%、76.82%和80.79%,工蚁诱集数量降幅分别达55.40%、47.21%和28.36%,随着时间延长,蚁巢数量和工蚁数量很快恢复。虽然随着施药剂量增加,蚁巢增加率和分巢率明显降低,新蚁巢出现时间略有延迟,新蚁巢的体积明显减小,但整体来看蚁巢数量仍呈上升趋势,新蚁巢出现的距离和方位也没有明显差异。表明粉剂防治仅可在短期内表面上压低红火蚁种群数量,即使...     

红火蚁信息素及其在化学防治中的应用研究进展

文章介绍了红火蚁的危害特征,分析了目前国内外红火蚁防治的主要方法,对利用化学信息素类物质防治红火蚁的研究方法及进展进行了综述;通过借鉴化学信息素在其他害虫防治中的应用,重点分析了化学信息素在红火蚁防治中的必要性和可能性,对红火蚁相关信息素的特点和化学结构进行了详细描述,并介绍了相关化学信息素的合成方法,揭示了信息素类物质在红火蚁综合防治中的重要性及优越性。     

Determining the most effective concentration of cypermethrin and the appropriate carrier particle size for fire ant (Hymenoptera: Formicidae) bait

BACKGROUND: The purpose of this study was to determine the most effective particle size of DDGS (distiller's dried grains with solubles) as fire ant bait carrier, as well as the most effective concentration of cypermethrin as a toxicant against the red imported fire ant (RIFA) Solenopsis invicta Buren under laboratory conditions. RESULTS: The DDGS particle size did not affect the fire ant's preference for the bait, but it did affect the mass of DDGS being carried back to the nest. The size of the DDGS particles and the mass of DDGS being carried back to the nest were positively correlated. The most efficient particle size of DDGS was 0.8–2 mm. The concentration of cypermethrin has a specific range for killing fire ants in an efficient manner. Neither a very low nor a very high concentration of cypermethrin was able to kill fire ants efficiently. The most effective concentration of cypermethrin was 0.13% in DDGS when mixed with 15% shrimp shell powders and 11% soybean oil. CONCLUSION: Based on its ability to kill fire ants when mixed with cypermethrin, as well as the advantage of having a larger area coverage when sprayed in the field, DDGS as the carrier and cypermethrin as the toxicant can be considered to be an efficient way to prepare fire ant bait for controlling fire ants in infested areas. Copyright © 2012 Society of Chemical Industry     

PGPR and entomopathogenic fungus bioformulation for the synchronous management of leaffolder pest and sheath blight disease of rice

BACKGROUND: The biological control of plant pests and diseases using a single organism has been reported to give inconsistent and poor performance. To improve the efficacy, bioformulations were developed possessing mixtures of bioagents. RESULTS: Bioformulations combining Pseudomonas fluorescens Migula strains Pf1 and AH1 and Beauveria bassiana (Balsamo) Vuill. isolate B2 were developed and tested for their efficacy against leaffolder pest and sheath blight disease on rice under glasshouse and field conditions. The combination of Pf1, AH1 and B2 effectively reduced the incidence of leaffolder insect and sheath blight disease on rice compared with other treatments. An in vitro assay of leaffolder preference to rice leaf tissues treated with Pf1 + AH1 + B2 biformulation showed variation from normal growth and development of leaffolder larvae. Plants treated with the Pf1 + AH1 + B2 combination showed a greater accumulation of enzymes, lipoxygenase and chitinase activity against leaffolder insect compared with other treatments. Similarly, the plants showed a higher accumulation of defence enzymes, peroxidase and polyphenol oxidase activity against sheath blight pathogen in Pf1 + AH1 + B2 treatment compared with the untreated control. The bioformulation mixture attracted the natural enemy population of leaffolder under field conditions. In addition, a significant increase in rice grain yield was observed in Pf1 + AH1 + B2 treatment compared with the untreated control. CONCLUSION: The combination of P. fluorescens strains and B. bassiana isolate effectively reduced the incidence of leaffolder insect and sheath blight disease on rice plants and showed the possibility of controlling both pest and disease using a single bioformulation. Copyright © 2010 Society of Chemical Industry     

外来物种红火蚁的化学防治技术

红火蚁的入侵已引起我国各界的关注,本文介绍了入侵红火蚁化学防治技术研究进展。按照化学防治策略可以分为以蚁巢为单元的局部处理和大面积全部处理,从施药技术角度可以分为浇灌和撒施毒饵两大类。浇灌技术主要是将药液灌入蚁巢内,其药液量是一个关键因子;毒饵适用的场所比较广泛,但是施药时间对控制效果影响比较大,一般在晚上施药效果较好,雨后不能马上使用毒饵。     

Photoprotection of Beauveria bassiana: Testing simple formulations for control of the coffee berry borer

The entomopathogenic fungus, Beauveria bassiana is considered to be one of the few natural enemies available for use against the coffee berry borer. In an attempt to enhance the efficacy of this pathogen, a range of concentrations of 22 substances was tested in simple laboratory tests using natural sunlight or a UV light source. Unprotected B. bassiana spores were almost completely inactivated by exposure to 60 min of direct sunlight or 20 s of UV light of 302 nm wavelength. Seven of the 22 substances tested showed little or no photoprotective properties and eight of the substances appeared directly detrimental to spore germination. Of the remainder, sucrose, yeast, yeast extract, uric acid, casein, and molasses had limited photoprotective properties. The most effective substances tested were egg albumen and skimmed milk powder which could extend the persistence of B. bassiana spores by a factor of almost three. A mixture of 3% (w/v) albumen and 4% (w/v) milk powder gave the highest degree of spore protection per unit cost. Young coffee plants sprayed with this mixture did not suffer any significant phytotoxic effects. A field trial, involving two applications of spores with or without the milk and albumen mixture, failed to show that improved spore persistence resulted in increased coffee berry borer control. Very lowlevels of pest infestation observed in field plots together with unusual, unfavourable weather conditions may have accounted for this unexpected result.     

Susceptibility of larvae and adults of Monochamus galloprovincialis to entomopathogenic fungi under controlled conditions

Six entomopathogenic fungal isolates were tested under controlled conditions, as biological control agents against Monochamus galloprovincialis (Coleoptera: Cerambycidae) (Olivier), the vector of the pine wood nematode Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) (Steiner and Buhrer). The fungi Beauveria bassiana (Bals.-Criv.) Vuill, Metarhizium anisopliae (Metchnikoff) Sorokin, Metarhizium sp. and Fusarium sp. were tested against larvae and adults of the insect, by comparing two exposure techniques: continuous contact and spraying. Regarding the larvae, only Fusarium sp. and Metarhizium sp. killed more than 40% of the individuals, while B. bassiana and M. anisopliae were found to kill 50% of the adults (LT₅₀) within five days. Exposure to B. bassiana reduced adult longevity by 19 days, when compared to untreated beetles, and had a direct efficacy of 46%. Continuous contact with the fungi proved to be more effective than spraying. A larval disinfection protocol was developed to eliminate other fungal isolates from the wood-collected tested individuals. The implications of the results and possible applications of selected strains as bio-control agents against M. galloprovincialis are discussed.     

Termite cuticular extracts improve acceptance of bait for controlling invasive Asian needle ants,Brachyponera chinensis

BACKGROUND

The Asian needle ant, Brachyponera chinensis, is an invasive ant currently spreading in urban and natural habitats throughout the eastern United States. Recent studies have documented the negative impact of B. chinensis on native ecosystems and human health, yet effective control strategies are lacking. Control difficulties are, in part, due to the unique biology of B. chinensis, which is a predatory ant and a termite specialist. Given that subterranean termites are an important nutritional resource for B. chinensis, the current study evaluated the potential of termite cuticular extract to improve the target-specificity and efficacy of commercial bait used for B. chinensis control.

RESULTS

The efficacy of bait augmented with termite cuticular extracts was evaluated in laboratory and field trials. In laboratory assays, B. chinensis colonies were offered granular bait treated with termite cuticular extract. Results demonstrated that the acceptance of commercial bait is significantly increased by the addition of termite cuticular extract or synthetic (Z)-9-pentacosene, a major component of termite cuticular extract. Foraging activity of Asian needle ants was significantly greater on baits augmented with termite cuticular extract or (Z)-9-pentacosene relative to standard bait. Furthermore, bait augmented with termite cuticular extract worked substantially faster relative to standard bait. To evaluate population effects, field studies were conducted in forested areas invaded by B. chinensis. Bait treated with termite cuticular extract scattered on the forest floor provided rapid control of B. chinensis and ant densities throughout the treated plots declined by 98% within 14 days.

CONCLUSION

The incorporation of termite cuticular extracts and individual cuticular hydrocarbons such as (Z)-9-pentacosene into traditional baits used for B. chinensis control may offer a novel tool to manage this increasingly problematic invasive ant. © 2023 The Author. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

球孢白僵菌定殖提高番茄对灰霉病抗性及其作用机理

为明确球孢白僵菌Beauveria bassiana定殖对番茄植株抗病性的影响及作用机理,采用灌根法将球孢白僵菌芽生孢子悬浮液接种于番茄植株内,并通过人工接种灰霉菌Botrytis cinerea评价球孢白僵菌定殖后番茄对灰霉病的抗性水平;检测灰霉菌胁迫下番茄植株不同位置叶片内球孢白僵菌的相对含量;测定番茄叶片内草酸氧化酶（oxalate oxidase,OXO）、几丁质酶（chitinase,CHI）和ATP合成酶（ATP synthase,atpA）3种抗病相关基因的表达量。结果表明,球孢白僵菌定殖能够提高番茄植株对灰霉病的抗性,接种灰霉菌第5天,番茄植株发病率、病斑直径和病情指数分别下降了61.6%、41.4%和26.4%;在灰霉菌胁迫下番茄植株内球孢白僵菌偏好于在病原菌感染位置定向聚集,并且引起植物抗病基因OXO、CHI和atpA的表达量上调。表明球孢白僵菌能通过内生定殖与植物互作提高植物抗病性,在植物病害生物防治领域有较大应用潜力。     

In vitro effects of flutriafol and azoxystrobin on Beauvaria bassiana and its efficacy against Tetranychus urticae

BACKGROUND: Testing the compatibility of chemical pesticides and fungal biocontrol agents is necessary if these two agents are to be applied together in the integrated management of plant pests and diseases. In this study, the fungicides azoxystrobin (a strobilurin) and flutriafol (a triazole) were tested in vitro for their effects on germination of conidia and mycelial growth of Beauveria bassiana (Bals.) Vuill. and in bioassay for their effect on fungal activity against Tetranychus urticae Koch. The fungicides were tested at three different concentrations [recommended rate for field use (1 × X) and the dilutions 10^?1× X and 10^?2× X]. RESULTS: Flutriafol inhibited growth of mycelia and germination of the fungal conidia at all concentrations tested in vitro, and also reduced the efficacy of B. bassiana in bioassays against mites. The inhibitive effect of azoxystrobin in vitro varied with the concentration applied. A significant effect was observed at 1 × X and 10^?1× X concentrations on both the germination of conidia and mycelia growth. At 10^?2× X concentration, azoxystrobin showed little effect on B. bassiana. However, when this fungicide was tested in bioassays, none of the concentrations reduced B. bassiana activity against mites. CONCLUSION: Azoxystrobin was most compatible with B. bassiana, while flutriafol was the most harmful. Further studies are required to confirm the negative effect of flutriafol on B. bassiana activity. Copyright © 2010 Society of Chemical Industry     

Effectiveness of thiamethoxam and imidacloprid seed treatments against Bemisia tabaci (Hemiptera: Aleyrodidae) on cotton

BACKGROUND: Bemisia tabaci (Gennadius) biotype B is one of the most important pests on cotton around the world. Laboratory, greenhouse and field experiments were conducted to determine the efficacy of thiamethoxam and imidacloprid seed treatments against B. tabaci on cotton. RESULTS: Under laboratory conditions, the two treatments caused whitefly adult mortality, reduced oviposition and increased mortality of nymphs at 10, 20, 30 and 40 days after germination (DAG). The longer the adults fed on plants from treated seeds, the higher the mortality. The two treatments did not have any effect on eggs. The efficacy of the treated seeds against B. tabaci gradually decreased from 10 to 40 DAG, being the lowest at 40 DAG. In laboratory experiments, the efficacies between the two treatments were similar. In greenhouse experiments, the two treatments were equally effective with lower numbers of whiteflies than untreated controls. With both treatments the concentrations of the active ingredient were gradually reduced with aging of the plants and from the bottom to the top leaves of the plants. Numbers of live whiteflies were well correlated with the dosage of active ingredients. Under field conditions, the seeds treated with both insecticides exhibited similar efficacy against B. tabaci for up to ～2 months. CONCLUSION: Cotton seeds treated with imidacloprid and thiamethoxam were effective against B. tabaci for up to 45 days under laboratory and greenhouse conditions, and up to ～2 months under field conditions. Use of imidacloprid‐ and thiamethoxam‐treated seeds can be an important alternative for management of whiteflies on cotton. Copyright © 2010 Society of Chemical Industry     

An auto-contamination trap-strips system for biological control of Hyphantria cunea (Lepidoptera: Noctuidae), an invasive pest in China

The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), is a major invasive pest in China, where it seriously threatens fruit and ornamental trees and windbreak systems. An auto-contamination trap-strips system was designed to disseminate Beauveria bassiana for biological control. The standard trap consisted of a yellow or green trap with a width no larger than 30 cm and with B. bassiana inside it. Therefore, the trap-strips provided an appropriate microenvironment for the fall webworm to pupate, and an acceptable humidity for B. bassiana to infect and reproduce. The average infection rates of the trap-strips systems were more than 90%. The present study demonstrated a practical application of how physical and biological control of this pest can be conducted efficiently and economically.     

亚蝗微粒子虫毒饵防治东亚飞蝗的研究

用亚蝗微粒子虫毒饵在室内和田间防治东亚飞蝗的试验结果表明，饵料含孢量约１×１０^１２个／ｋｇ，投放量２ｋｇ／６６７ｍ^２，于蝗蝻２龄期施用，１４ｄ内可获得８７．８％的杀蝻效果     

Sublethal effect of Beauveria bassiana on feeding and fecundity of the sunn pest,Eurygaster integriceps Puton (Hemiptera: Scutelleridae)

The sunn pest, Eurygaster integriceps Puton, is a major pest of wheat in West and Central Asia. Studies were conducted to investigate the effect of Beauveria bassiana (teleomorph; Cordyceps bassiana) isolates on the sunn pest. Bioassays were done with adult insects collected from overwintering sites at three different times. The effect of sublethal doses of fungi on the insects’ feeding and fecundity was determined. When the sunn pest adults were treated with 2 × 10⁷ conidia mL^?1, all isolates caused significant sunn pest mortality varying between 24 and 100% 12 days after inoculation. There were significant differences between mortality, depending on the date of fungal application. Adult sunn pests treated with B. bassiana at sublethal concentrations caused significantly less damage to wheat leaves than sunn pests in the control. The number of eggs laid by the sunn pest was significantly fewer when wheat plots in plastic greenhouse and field cages were infested with adult sunn pests treated at sublethal concentrations, compared with sunn pests in control plots. Results show that sublethal dosages of B. bassiana reduced sunn pest feeding and fecundity. Applying B. bassiana in sunn pest overwintering sites minimizes the pest populations, which would move to wheat fields in spring.     

Endophytic Beauveria bassiana activates expression of defence genes in grapevine and prevents infections by grapevine downy mildew Plasmopara viticola

Fungal entomopathogens like Beauveria bassiana (Ascomycota: Hypocreales) are known as antagonists of insects with multiple functional and ecological roles, and have attracted increased attention as biocontrol agents in integrated pest management programmes. For some crop plants, it has been proven that endophytic B. bassiana, besides its entomopathogenic habit, can provide protection against plant pathogens or limit their damaging effects. However, for grapevine, limited knowledge is available on the influence of endophytic B. bassiana on fungal pathogens and about the mechanisms underlying putative protection effects. This study assessed the protective potential of endophytic B. bassiana against grapevine downy mildew Plasmopara viticola in greenhouse experiments. Three and seven days after a B. bassiana treatment, potted grapevine plants were inoculated with P. viticola and the evolving disease severity was assessed. Disease severity was significantly reduced in B. bassiana-treated plants compared to control plants, depending on the age of leaves. Furthermore, a microarray and an RT-qPCR analysis were performed to work out fundamental aspects of genes involved in the interaction between grapevine and B. bassiana. The results indicate an up-regulation of diverse defence-related genes in grapevine as a response to endophytic establishment of B. bassiana. Thus, endophytic establishment of an entomopathogenic fungus such as B. bassiana in grapevine plants would represent an alternative and sustainable plant protection strategy, with the potential for reducing pesticide applications in viticulture.     

Laboratory and field cage studies on female‐targeted attract‐and‐kill bait stations for Anastrepha suspensa (Diptera: Tephritidae)

BACKGROUND: Development of attract‐and‐kill bait stations for pest fruit flies has been limited by the water solubility of sugar needed as a feeding stimulant and by the volatility of chemical attractants. A wax‐based matrix was developed that provides the longevity needed for field use and is biodegradable. RESULTS: Laboratory bioassays with the Caribbean fruit fly, Anastrepha suspensa (Loew), confirmed the efficacy of bait stations containing avermectin, methomyl, spinosad and phloxine B. Field cage studies demonstrated that significant mortality occurred with either 1% (w/v) spinosad or 1% (w/v) methomyl bait stations versus pesticide‐free bait stations. Bait stations were exposed to environmental conditions by placing them in trees at the ARS station in Miami, Florida, between tests. There was no loss in efficacy, in spite of exposure to over 360 mm of rainfall over the 56 days of the study, indicating that the bait stations could provide population suppression for at least 1–2 months when used in subtropical environments. CONCLUSION: A long‐lasting, female‐targeted fruit fly bait station, such as the one developed herein, could provide a cost‐effective option for fruit fly population suppression that would be an important tool in tephritid pest management and control. Additional studies are needed to demonstrate efficacy against wild fruit fly populations and determine deployment strategies. Copyright © 2009 Society of Chemical Industry     

Effect of <Emphasis Type="Italic">Beauveria bassiana</Emphasis> mixed with diatomaceous earth on mortality,mycosis and sporulation of <Emphasis Type="Italic">Rhyzopertha dominica</Emphasis> on stored wheat

A laboratory assay was designed to determine the insecticidal efficacy of Beauveria bassiana (Balsamo) Vuillemin (Hyphomycetes: Moniliales) and diatomaceous earth (Diafil 610) against Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae). The fungus B. bassiana was applied at 2.23 × 10⁷, 2.23 × 10⁸ and 2.23 × 10⁹ conidia kg⁻¹ of wheat individually as well as mixed with 200 and 400 ppm of Diafil 610. The conditions for the trials were 30 ± 2^oC with 55% r.h. and the counts for mortality were made after 8, 16 and 24 d. All the dead adults were removed after each count and the vials were kept for the next 60 d to assess the emergence of the F₁ generation. The findings from these studies proved that the extended exposure interval and the highest combined dose rate of the entomopathogenic fungus and the diatomaceous earth gave the maximum mortality of the beetles. The emergence of the progeny was also highly suppressed where the maximum dose rate of the synergized treatments was applied. The rate of mycosis and sporulation in the cadavers of R. dominica was maximum where the low dose rates of B. bassiana were applied.     

The Use of Confined Colonies of Wild Mice (Mus musculus L.) in the Evaluation of Rodenticides1

Experimental studies have been conducted using penned families of wild house mice (Mus musculus L.) treated with different rodenticides and subjected to various poisoning regimes. The results showed that such investigations on rodents can provide valuable post-laboratory information on the relative merits and the best mode of application of rodenticides prior to their examination under field conditions. Pen population studies also permit closer study of feeding activity, bait acceptance, social behaviour and other factors that can affect rodenticidal efficacy.     

Biological control of Cimex lectularius with Beauveria bassiana: Effects of substrate,dosage, application strategy,and bed bug physiology

Background

Cimex lectularius L. (bed bug) (Hemiptera: Cimicidae) is a serious indoor pest worldwide, and this nuisance needs to be controlled using different methods in integrated pest management (IPM). Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) kills bed bugs, and insect pathogenic fungi may be utilized to control bed bugs in IPM. To increase knowledge of this methodology, forced exposure experiments were conducted with different formulations, doses, and substrates, using bed bugs in variable physiological states.

Results

Both oil- and water-formulated fungal products showed significant improvement when conidial concentrations were raised in five steps from 0.02 to 2.0%. At low concentrations (0.02% in water) effects from substrate and application strategy were observed. Application on soft substrates (cotton and polyester) yielded significantly higher bed bug mortality rates than on harder substrates (paper, wood, and linoleum) with a final mortality of 35–63% against 8–10%. Multiple applications over time also improved B. bassiana's ability to kill bed bugs, and at low concentrations only a triple application on cotton showed 100% final mortality. Bed bug age and reproductive status significantly affected survival. Older and reproducing individuals showed higher mortality compared to newly emerged adults. Differences in feeding status also yielded differences in mortality timing, but only minor differences in final mortality rates. Egg production and hatching success were significantly reduced by some treatments.

Conclusion

B. bassiana appears to be an asset in the fight against bed bugs. Substrate, dosage, application strategy, and bed bug physiology are important factors to consider for optimal efficacy and safe indoor control with insect pathogenic fungi. © 2023 Society of Chemical Industry.