Evaluation of semiochemical based push-pull strategy for population suppression of ambrosia beetle vectors of laurel wilt disease in avocado.

Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae and Platypodinae) bore into tree xylem to complete their life cycle, feeding on symbiotic fungi. Ambrosia beetles are a threat to avocado where they have been found to vector a symbiotic fungus, Raffaelea lauricola, the causal agent of the laurel wilt disease. We assessed the repellency of methyl salicylate and verbenone to two putative laurel wilt vectors in avocado, Xyleborus volvulus (Fabricius) and Xyleborus bispinatus (Eichhoff), under laboratory conditions. Then, we tested the same two chemicals released from SPLAT flowable matrix with and without low-dose ethanol dispensers for manipulation of ambrosia beetle populations occurring in commercial avocado. The potential active space of repellents was assessed by quantifying beetle catch on traps placed 'close' (~5-10 cm) and 'far' (~1-1.5 m) away from repellent dispensers. Ambrosia beetles collected on traps associated with all in-field treatments were identified to species to assess beetle diversity and community variation. Xyleborus volvulus was not repelled by methyl salicylate (MeSA) or verbenone in laboratory assays, while X. bispinatus was repelled by MeSA but not verbenone. Ambrosia beetle trap catches were reduced in the field more when plots were treated with verbenone dispensers (SPLAT) co-deployed with low-dose ethanol dispensers than when treated with verbenone alone. Beetle diversity was highest on traps deployed with low-dose ethanol lures. The repellent treatments and ethanol lures significantly altered the species composition of beetles captured in experiment plots. Our results indicate that verbenone co-deployed with ethanol lures holds potential for manipulating ambrosia beetle vectors via push-pull management in avocado. This tactic could discourage immigration and/or population establishment of ambrosia beetles in commercial avocado and function as an additional tool for management programs of laurel wilt

Uso do feromônio sexual sintético para captura de machos da traça-das-crucíferas

The aim of this work was to study the attractiveness of males of Plutella xylostella L. (Lepidoptera: Yponomeutidae) to different formulations of synthetic sex pheromone. The treatments were: 1) commercial formulation; 2) Z-11,16:Ald; 3) Z-11,16:Ac; 4) binary blends 7:3 of 2+3; 5) binary blends 5:5 of 2+3; 6) rubber septa with hexane (control); 7) five virgin females. The commercial formulation of the synthetic sex pheromone was more attractive to males, and did not differ significantly from virgin females and binary blends 5:5 treatments. The components alone were less attractive to males. Five traps were evaluated: Pherocon 1 CP (wing trap), Delta, "PVC 200", "PVC 250" and Black Round Trap, where the wing trap was more effective in capturing males than the other traps tested. The wing trap was evaluated at 5, 30 and 60 cm. More males were caught at 30 cm above the ground level, while the height of 5 and 60 cm did not differ significantly.Este trabalho teve como objetivo estudar a atração dos machos da traça-das-crucíferas (Plutella xylostella L., Lepidoptera: Yponomeutidae) por diferentes formulações do feromônio sexual sintético. Os tratamentos consistiram em: 1) formulação comercial; 2) Z-11,16:Ald; 3) Z-11,16:Ac; 4) mistura 7:3 de 2+3; 5) mistura 5:5 de 2+3; 6) septos de borracha com hexano (testemunha); e 7) cinco fêmeas virgens. A formulação comercial do feromônio sexual sintético propiciou maior captura de machos, não diferindo significativamente de fêmeas virgens e da mistura 5:5 utilizadas como isca. Os componentes isoladamente foram pouco atrativos aos machos. Foram testados cinco modelos de armadilhas. A armadilha Pherocon 1 CP (33,2 machos/armadilha/noite) foi a mais eficiente na captura de machos, seguida pelas armadilhas Cilíndrica Aberta, Cilíndrica Fechada, Delta e Redonda Aberta. Três alturas de instalação da armadilha foram avaliadas. Ocorreu significativamente maior captura de machos na altura do ápice das plantas (30 cm do solo). As alturas de 5 e 60 cm não diferiram entre si

Insect pest management with sex pheromone precursors from engineered oilseed plants

Pheromones have become an environmentally friendly alternative to conventional insecticides for pest control. Most current pheromone-based pest control products target lepidopteran pests of high-value crops, as today’s manufacturing processes cannot yet produce pheromones at low enough costs to enable their use for lower-value crops, especially commodity crops. Camelina sativa seeds genetically modified to express (Z)-11-hexadecenoic acid, a sex pheromone precursor of several moth species, provided the oil from which the precursor was isolated, purified and transformed into the final pheromone. Trap lures containing this pheromone were then assessed for their capacity to manage moth pests in the field. Plant-derived pheromone lures proved equally effective as synthetic pheromone lures in monitoring the diamondback moth, Plutella xylostella, in cabbage and disrupting mating of cotton bollworm, Helicoverpa armigera, in common bean fields. Our study demonstrates the biological efficacy and economic feasibility of pheromone production in plant factories by metabolic engineering of an oilseed crop

Monitoramento e supressão populacional de Pectinophora gossypiella Sauders 1844, (Lepidoptera, gelechudae), com o uso do seu feromonio sexual

Orientador: Mohamed E. E. Mostafa HabibDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Pectinophora gossypiella é uma praga da cultura algodoeira. Devido a características comportamentais e de desenvolvivento, esta espécie tem seus indivíduos jovens extremamente protegidos das formas usuais de controle. Os indivíduos adultos se expõem mais durante o período noturno, devido à procura de parceiros sexuais, alimentação e sítios de oviposição. No presente trabalho fez-se uso de feromônios sexuais para se exercer o controle populacional do gelequídeo. Utilizou-se feromônio gossylplure técnico microcapsulado nas técinicas de confusão de machos e atrai-mata. Foram testada técnicas de armadilhamento, utilizando dois tipos de armadilhas caseiras ¿ de papel colante e de óleo lubrificante 'queimado¿ ¿ numa proporção de 20 armadilhas por hectare, tendo sido obtidoas excelentes resultados em relação á supressão populacional da praga. A armadilha de papel colante para que mantenha seu poder de captura de machos do guelequídeo no pico máximo. O levantamento de inimigos naturais foi efetuado durante a safra e entressafra, tendo sido registrado pela primeira vez no Brasil Bacillus cereus causando mortalidade em larvas de final de ciclo. Bracon vulgaris é o parasito mais constante e efetivo no controle das populações de larvas P. gossypiella no período de meio e final de ciclo vegetativo do algodão. ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digitalAbstract: The Pink bollworm, Pectinophora gossypiella, is one of the principal cotton pests. The usual chemical do not control esfficiently the pest, because of it¿s developmental and behavioral caracteristics. Only the adult individuals expose theselves at night when they look for sexual partners, oviposition and food sites. In this work we used the sexual pheromone to control the Gelechiidae. We used the microencapsulated technical gossyplure in the male confusion and attract-and-kill techniques. We tested trapping techniques using two easy-to-make traps, one with paper with permanent glue and another with used car oil, on the desity of 20 traps/ha, with good results in the pest population than the paper with glue to mantainance of its high power of moth capture. We surveyed the natural enemies of PBW durin the cotton growing seasons and in between, when we registered for first time in Brazil the PBW mortality caused by Bacillus cereus. The parasite Bracon vulgaris is the most effective in controlling the larvae populations towards the end of the growing season. ...Note: The complete abstract is available with the full electronic digital thesis or dissertationsMestradoEcologiaMestre em Ciências Biológica