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Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) cryptic species complex represents a major threat to several important crops including vegetables, cereals, fruits, and ornamentals worldwide. One important mode of its dispersal is through the trans-boundary (domestic, international) movement of infested plant materials. To prevent the spread of this invasive insect pest on inter-state ornamental shipments, the efficacy of biopesticides was tested through dip treatments of plant material pre-shipping. In several experiments, clean Mentha sp. (Lamiaceae), mint plants were exposed to adults of B. tabaci for 1 or 6 days. Adults were removed from plants and eggs, and immature stages were treated with one or a combination of the following: entomopathogenic fungi Beauveria bassiana (BotaniGard ® ), Isaria fumosorosea (Preferal ® ), the surfactant Natur'l Oil™, and soap (Publix ® ). After treatment application, plants were placed in commercial cardboard boxes and shipped from Apopka, Florida (FL) to Fort Pierce, FL. Assessments for the treatment efficacies were conducted at 3, 7, and 14 days post arrival of the shipment. Fungal entomopathogens; B. bassiana, I. fumosorosea , and the surfactant Natur'l Oil™, showed significant reduction in the whitefly population compared to the untreated control ( P  < 0.05). Significantly higher corrected mortality of the whitefly populations was observed when B. bassiana was applied alone (81%) or in combination with Natur'l Oil™ (86%), as well as I. fumosorosea applied in combination with Natur'l Oil™ (77%). Our results showed that pre-shipping dip treatment applications of either Natur'l Oil™ mixed with B. bassiana or I. fumosorosea or B. bassiana applied alone could help mitigate the inter-state spread of whitefly on ornamental shipments. [ABSTRACT FROM AUTHOR]

Spotted ( Diabrotica undecimpunctata howardi) and striped ( Acalymma vittata) cucumber beetles are significant pests of cucurbits, and organic management options are limited. Beetle feeding results in aesthetic damage and reduction in marketable yields as well as transmission of bacterial wilt resulting in plant mortality. Biopesticides are formulated from naturally occurring organisms such as fungi and bacteria that are pathogenic or toxic to insect pests and may be used in organic production systems. These products are thought to have lower risk to non-target organisms including mammals and beneficial insects. This research examined the potential of novel microbial products and fungal organisms to reduce cucumber beetle damage on melons. Laboratory bioassays were performed to evaluate the efficacy of a bacterial extract of Chromobacterium subtsugae and two common strains of entomopathogenic fungi, Beauveria bassiana and Isaria fumosorosea, on cucumber beetles in a controlled environment. Trials were performed against adult beetles in organic field experiments on muskmelon ( Cucumis melo L. cv. reticulatus Ser.). Prior to testing in the field, anti-feedant effects were observed when beetles were exposed to leaves with Chromobacterium subtsugae and Beauveria bassiana in the laboratory. However, in field applications, we did not observe a reduction in beetle populations below the economic threshold levels, and subsequently, there was no yield increase compared to the control. Additional research is needed to improve biopesticide efficacy through formulation and timing of delivery, determine efficacy on multiple life stages of the pest, and understand interactions of microbial biopesticides in the environment and potential for non-target impacts in organic systems. [ABSTRACT FROM AUTHOR]

The efficacy of topical, leaf residue, and soil drench applications with Isaria fumosorosea blastospores (Ifr strain 3581) was assessed for the management of the citrus root weevil, Diaprepes abbreviatus (L.). Blastospores of Ifr were applied topically at a rate of 107 blastospores mL-1 on both the larvae and adults, and each insect stage was incubated in rearing cups with artificial diet at 25 °C, either in the dark or in a growth chamber under a 16 h photophase for 2 weeks, respectively. Percent larval and adult mortality due to the infection of Ifr was assessed after 14 days as compared to untreated controls. Leaf residue assays were assessed by feeding the adults detached citrus leaves previously sprayed with Ifr (107 blastospores mL-1) in Petri dish chambers and then incubating them at 25 °C for 2-3 weeks. Efficacy of the soil drench applications was assessed on five larvae feeding on the roots of a Carrizo hybrid citrus seedling ~8.5-10.5 cm below the sterile sand surface in a single 16 cm × 15.5 cm pot inside a second pot lined with plastic mesh to prevent escapees. Drench treatments per pot consisted of 100 mL of Ifr suspension (107 blastospores mL-1), flushed with 400, 900, or 1400 mL of water compared to 500, 1000, and 1500 mL of water only for controls. The mean concentration of Ifr propagules as colony forming units per gram (CFUs g-1) that leached to different depths in the sand profile per treatment drench rate was also determined. Two weeks post-drenching of Ifr treatments, larvae were assessed for percent mortality, size differences, and effect of treatments in reducing feeding damage to the plant root biomass compared to the controls. Topical spray applications caused 13 and 19% mortality in larvae and adults after 7 days compared to none in the control after 14 days, respectively. Adults feeding on a single Ifr treated leaf for 24 h consumed less than the control, and resulted in 100% mortality 35 days post-treatment compared to 33% in the untreated control. Although offered fresh, untreated leaves after 24 h, only adults in the control group consumed them. Ifr CFUs g-1 were isolated 8.5-10.5 cm below the sand surface for the 1000 and 1500 mL drench rates only, resulting in 2%-4% larval mortality. For all the Ifr drench treatments, no differences were observed in percent larval mortality and size or the effect of treatments in reducing feeding damage to the plant root biomass compared to the controls. These results suggest that the foliar application of Ifr may be an efficient biocontrol strategy for managing adult populations of D. abbreviatus; potential alternative larval management strategies are discussed. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study that evaluated the commercial strains of entomopathogenic fungi against chilli thrips, Scirtothrips dorsalis, an invasive pest of ornamental and vegetable plants in the Caribbean and U.S. The overall Scirtothrips dorsalis populations on pepper plants, Capsicum annum was reduced with three applications of mycoinsecticides and other biorational insecticides. It concluded that mycoinsecticides are effective pest management strategy.

A laboratory bioassay was developed to evaluate strains of Isaria fumosorosea Wize, against Diaphorina citri. Up to 100% of adult psyllids were killed at concentrations between 106 and 107 blastospores/ml after 12 days, with derived LC50 values (at 7 days post treatment) between 1.4 × 105 and 2.0 × 106 blastospores/ml for strains ARSEF 3581, FE 9901 and Apopka-97. A significantly higher value (1.5 × 107) was obtained with a conidial formulation of Apopka-97. Average survival times were dosage dependent, i.e. between 10.2 days at 103 blastospores/ml and 3.5 days at 108 blastospores/ml. Rates of mycosis were also dosage dependent, with up to 100% sporulation on cadavers at 108 blastospores/ml but declining at lower concentrations. The Apopka-97 strain (commercially available as PFR-97) was tested against established D. citri infestations in potted citrus in greenhouse cages. Treatments at label rates reduced psyllid populations by approximately 50% over 3 weeks. The combination of PFR-97 with emulsifiable oils (0.25% v/v) did not increase psyllid mortality compared with either agent alone. Imidacloprid applied as a drench killed 100% of psyllids within 3 weeks. Subsequent greenhouse tests during humid conditions were hampered by natural dissemination of I. fumosorosea to untreated psyllids, suggesting that this fungus is spread by air movement and may be highly effective under very humid conditions. In later tests, a Cladosporium sp. rapidly colonised psyllid cadavers and leaf surfaces, but was not pathogenic in laboratory tests. Our studies confirm the potential of I. fumosorosea to be used in IPM strategies for D. citri that rely on other tactics, such as insecticidal oils and native or introduced biological control agents. [ABSTRACT FROM AUTHOR]

Simple Summary: Citrus greening is devastating the citrus industry in Florida, and conventional synthetic pesticide applications are rapidly becoming unsustainable for the control of the vector, the Asian citrus psyllid (AsCP), Diaphorina citri. Laboratory experiments indicate that the entomopathogenic fungus Cordyceps javanica, alone and in combination with horticultural oils, may offer a more sustainable strategy to manage AsCP. The field study in this paper indicated that C. javanica alone, C. javanica mixed with white oil, and spinetoram (the chemical standard) mixed with white oil significantly suppressed AsCP populations by 60–90% and 61–83% 7 and 14 days after treatment, respectively, in 2018, compared to white oil only and the untreated control treatments. Only spinetoram + oil suppressed AsCP 100% up to 7 days after treatment in 2019. AsCP's natural enemies, mostly lady beetles, were observed on fungal-treated citrus trees and the untreated control. Overall, C. javanica was as effective in suppressing AsCP adults as spinetoram for up to 14 days in field conditions and was compatible with the psyllids' natural enemies. The use of C. javanica in citrus-integrated pest management is suggested. Citrus greening disease is devastating the citrus industry in Florida, and the conventional synthetic pesticide applications used to control the vector, the Asian citrus psyllid (AsCP), Diaphorina citri, are rapidly becoming unsustainable. Various laboratory experiments indicate that the entomopathogenic fungus Cordyceps javanica, alone and in combination with horticultural oils, may offer a more sustainable strategy for the management of AsCP. Field studies conducted in 2018 and 2019 in mature citrus indicated that C. javanica alone, C. javanica mixed with white oil, and the chemical standard spinetoram mixed with white oil significantly suppressed AsCP adult populations by 61–83% up to 14 days after treatment in 2018, although colony-forming units of C. javanica were still present on the leaves 21 days after treatment (DAT). Only spinetoram + oil significantly suppressed AsCP, by 100%, up to 7 DAT in 2019. Natural enemies of AsCP, including lady beetles, lacewing larvae and the parasitoid Tamarixia radiata, were observed in the fungal treatments and the untreated control. The AsCP suppression by C. javanica and its compatibility with beneficial organisms suggest the potential use of this entomopathogenic fungus in citrus-integrated pest management. [ABSTRACT FROM AUTHOR]

Simple Summary: The solanum whitefly, Aleurothrixus trachoides, is a polyphagous pest known to attack > 70 crops worldwide. Endemic to the Neotropical region, in the past few years, it has emerged as a significant pest of several horticultural crops including pepper in the United States. To develop an eco-friendly sustainable management strategy for this pest, in this study, we evaluated the efficacy and compatibility of two commercially available biological control agents, predatory beetle Delphastus catalinae (Dc) and entomopathogenic fungi Cordyceps fumosorosea (Cfr) under laboratory conditions. Results showed both Cfr, treatments (alone or in combination with Dc) were efficacious, and Cfr did not negatively impact the beetle longevity. This study's outcome is important not only for organic horticultural growers, but also for conventional growers as it offers a low-risk alternative tool for solanum whitefly integrated pest management in Florida and other affected regions. Aleurothrixus (formerly known as Aleurotrachelus) trachoides Back (Hemiptera: Aleyrodidae), commonly known as pepper or solanum whitefly, is a new emerging whitefly pest of several horticultural crops in the United States. During the preliminary survey for pepper whitefly infestation in Florida, a whitefly-specific predatory beetle Delphastus catalinae Horn (Coleoptera: Coccinellidae) was observed associated with this pest in the natural ecosystem. The current study was undertaken to determine the efficacy of this naturally occurring predator, D. catalinae, and an entomopathogenic fungus, Cordyceps (formerly known as Isaria) fumosorosea (Cfr) (Wize) (Hypocreales: Cordycipitaceae), alone or in combination, under controlled laboratory conditions. Whitefly mortality for Cfr (88%), beetle (100%) and Cfr + beetle (100%) treatments were similar and significantly higher compared to control. In the combination treatment, Cfr did not impact D. catalinae longevity and daily food intake, indicating a neutral interaction between the two treatments. Results showed that both of these natural biological control agents could potentially offer an effective alternative in the battle against invasive whiteflies such as pepper whitefly in U.S. horticulture production, either as a stand-alone strategy or in an integrated approach. Although these findings are promising, compatibility of the two treatments needs to be evaluated further under greenhouse and semi-field conditions before recommending to commercial growers. [ABSTRACT FROM AUTHOR]

The efficacy of entomopathogenic fungi [Beavueria bassiana (Bb08, Bb10) and Isaria fumosorosea (Ifr)] isolated from different regions of Southern Tamil Nadu, India was assessed against red cotton stainer, Dysdercus cingulatus. All the tested isolates showed 100% mortality. The B. bassiana isolates such as Bb08, Bb10 and an I. fumosorosea isolates exemplified the significant mortality among the isolates tested. LC50, LC90 and correlation coefficient were calculated for mortality. Bb08, Bb10 and Ifr isolates unveiled the lowest LC50 (5.9 x 105, 6.6 x 105 and 2.6 x 105) and LC90 (1 x 109, 7.3 x 108 and 3.9 x 108) value compared to the isolates tested. Highly significant correlation co-efficient was observed in the isolates Bb08, Bb10 and Ifr. [ABSTRACT FROM AUTHOR]