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1.
Insects ; 15(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38392543

RESUMO

The rainfall regime has a significant impact on the microclimate and mass emergence of the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae) (CBB). Little is known, however, about the shade tree-microclimate-CBB mass emergence interaction. The objective of the present study was to compare the effect of microclimate on the mass emergence of CBB in a full sun-exposed plot with a plot shaded by trees. The experiment was conducted on a Robusta coffee farm in southern Chiapas, Mexico. In each plot, 18 traps baited with an alcohol mixture were installed to capture flying females, collecting caught individuals every hour from 8:00 to 18:00 h. A meteorological station recorded several microclimatic variables on 13 weekly sampling dates from February to May 2022. Significantly more CBB females were captured in the shaded plot. The largest number of CBB captures was recorded between 14:00 and 16:00 h for the shade plot and between 15:00 and 17:00 h for the sun-exposed plot. The mass emergence of CBB showed a positive association with precipitation, dew point, and wind speed samples and a negative association with maximum air temperature, average relative humidity, ultraviolet radiation, wind speed, and equilibrium moisture content. Our observations show that the relationship between shade trees, microclimate, and mass emergence of CBB is complex and that its study helps us to gain deeper insight into CBB bioecology and advance control techniques against this important pest.

2.
Agron Sustain Dev ; 41(5): 62, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484434

RESUMO

In Latin America, the cultivation of Arabica coffee (Coffea arabica) plays a critical role in rural livelihoods, biodiversity conservation, and sustainable development. Over the last 20 years, coffee farms and landscapes across the region have undergone rapid and profound biophysical changes in response to low coffee prices, changing climatic conditions, severe plant pathogen outbreaks, and other drivers. Although these biophysical transformations are pervasive and affect millions of rural livelihoods, there is limited information on the types, location, and extent of landscape changes and their socioeconomic and ecological consequences. Here we review the state of knowledge on the ongoing biophysical changes in coffee-growing regions, explore the potential socioeconomic and ecological impacts of these changes, and highlight key research gaps. We identify seven major land-use trends which are affecting the sustainability of coffee-growing regions across Latin America in different ways. These trends include (1) the widespread shift to disease-resistant cultivars, (2) the conventional intensification of coffee management with greater planting densities, greater use of agrochemicals and less shade, (3) the conversion of coffee to other agricultural land uses, (4) the introduction of Robusta coffee (Coffea canephora) into areas not previously cultivated with coffee, (5) the expansion of coffee into forested areas, (6) the urbanization of coffee landscapes, and (7) the increase in the area of coffee produced under voluntary sustainability standards. Our review highlights the incomplete and scattered information on the drivers, patterns, and outcomes of biophysical changes in coffee landscapes, and lays out a detailed research agenda to address these research gaps and elucidate the effects of different landscape trajectories on rural livelihoods, biodiversity conservation, and other aspects of sustainable development. A better understanding of the drivers, patterns, and consequences of changes in coffee landscapes is vital for informing the design of policies, programs, and incentives for sustainable coffee production. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13593-021-00712-0.

3.
Arthropod Struct Dev ; 45(3): 294-300, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26806764

RESUMO

The morphology of the first instars of the Opiinae braconids Diachasmimorpha longicaudata, Doryctobracon areolatus, Doryctobracon crawfordi, Utetes anastrephae and Opius hirtus (the first is exotic, and the others are natives to Mexico), parasitoids of Anastrepha fruit flies, are described and compared. The possible implications on interspecific competition among these species are discussed. The most significant adaptations found were: (1) the mouth apparatus, where the large mandibles and fang-shaped maxillary lobes present in D. longicaudata and U. anastrephae larvae were absent in O. hirtus, D. areolatus and D. crawfordi larvae, and (2) the degree of mobility for exploration and escape, such as the lateral and caudal appendages that were only present in D. longicaudata (ventrolateral appendages in the base of the head capsule), U. anastrephae (caudal lobe with two appendages) and D. areolatus (caudal lobe with a round apex with a globular shape). The first instar larvae of the species D. longicaudata show morphological adaptations that apparently confer competitive advantages against the larvae of D. areolatus, D. crawfordi and O. hirtus. However, the first instar larvae of U. anastrephae show larger mandibles, an adaptation that could enable this species to resist competition from D. longicaudata.


Assuntos
Adaptação Fisiológica , Tephritidae/parasitologia , Vespas/ultraestrutura , Animais , Comportamento Competitivo , Interações Hospedeiro-Parasita , Larva/fisiologia , Larva/ultraestrutura , Especificidade da Espécie , Vespas/fisiologia
4.
Rev. bras. entomol ; 56(1): 95-100, jan.-mar. 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-624640

RESUMO

The importance of age and feeding on the performance of Cephalonomia stephanoderis (Hymenoptera, Bethylidae), a parasitoid of the coffee berry borer, Hypothenemus hampei (Coleoptera, Curculionidae) was investigated in the laboratory. Groups of female parasitoids were subject to the following treatments: a group fed during one, five and ten days after emergence of adults with coffee borer larvae; another group fed only with honey solution during five days after emergence; and as a control, a third group was kept without food for five days. At the end of each treatment, survivorship, parasitoid activity (walking and flying capacity in an arena), search capacity for finding coffee borer-infested berries, host feeding and oviposition (on immature hosts), were assessed. Unfed females showed a significant decrease in survivorship compared to individuals that were fed. The type of meal (insects or honey) did not significantly influence parasitoid activity, search and oviposition capacities. Females fed with honey solution significantly consumed less immature coffee borers. Younger females (one day old) walked and flew out of the arena significantly faster than older ones (5 and 10 days old). Implications of these results are discussed on the performance of C. stephanoderis as a biological control agent of the coffee berry borer.


A importância da idade e da alimentação no desempenho de Cephalonomia stephanoderis (Hymenoptera, Bethylidae) parasitóide da broca-do-café, Hypothenemus hampei (Coleoptera, Curculionidae) foi investigada em laboratório. Grupos de parasitóides fêmeas foram submetidos aos seguintes tratamentos: um grupo alimentado durante um, cinco e 10 dias após a emergência dos adultos sobre as larvas da broca-do-café; outro grupo foi alimentado apenas com uma solução de mel, durante cinco dias após a emergência; e como controle, um terceiro grupo foi mantido sem alimento por cinco dias. No final de cada tratamento de sobrevivência, a atividade do parasitóide (capacidade de andar e voar numa arena), a capacidade de busca (de encontrar frutos de café infestados com a broca), consumo do hospedeiro e oviposição (em hospedeiros imaturos), foram avaliados. Fêmeas em jejum mostraram uma diminuição significativa na sobrevivência de indivíduos em relação à alimentação. O tipo de alimento (insetos ou mel) não influenciou significativamente a atividade de busca do parasitóide e capacidades de oviposição. As fêmeas alimentadas com solução de mel consumiram significativamente menor número de imaturos da broca-do-café. Fêmeas mais jovens (um dia) andaram e voaram da arena significativamente mais rápido que as mais velhas (5 e 10 dias de idade). Implicações desses resultados são discutidas sobre o desempenho de C. stephanoderis como um agente de controle biológico da broca-do-café.

5.
J Econ Entomol ; 100(2): 291-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17461049

RESUMO

The virulence of two products of the fungus Beauveria bassiana (LCPP and Bassianil) on adult Anastrepha ludens (Loew) (Diptera: Tephritidae) and their effect on the mating performance of infected males was evaluated in laboratory and field cage tests. The horizontal transmission capacity of the fungus during copulation or attempted copulation also was quantified using inoculated males as well as the impact of infection on female fecundity and longevity. Both fungal products were found to be highly virulent (LCPP, mortality = 98.7% at 1 x 10(8) conidia per ml, LT50 = 4.20 d, LC50 = 9.35 x 10(5) conidia per ml; Bassianil, mortality = 99.3% at 1 X 10(8) conidia per ml, LT50 = 4.04 d, LC50 = 2.69 x 10(7) conidia per ml). Mating success of inoculated males was not affected compared with the control group during the 3 d postinoculation. Horizontal transmission to females during the first day was 80.6 and 84.3% through mating and 15.4 and 21.6% through attempts to mate and contact during courtship for the LCPP and Bassianil products, respectively. The fertility of infected females was notably reduced, and longevity did not extend beyond 15 d. Our results suggest the possibility of using sterile flies as fungus vectors in sterile insect technique programs, but the potential benefits and shortcomings of this approach require further investigation.


Assuntos
Beauveria/patogenicidade , Tephritidae/microbiologia , Animais , Transmissão de Doença Infecciosa , Feminino , Fertilidade , Longevidade , Masculino , Comportamento Sexual Animal
6.
J Econ Entomol ; 98(3): 821-35, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16022311

RESUMO

Three new types of traps designed and made by farmers were evaluated for capture of Idiarthron subquadratum Saussure & Pictet. Bag, sack, and fabric traps were compared with previously used bamboo internode traps. A participatory methodology was used involving farmer interviews and workshops to design and make the traps. Farmer participation was useful for obtaining information on perceptions, knowledge, and control activities of I. subquadratum. The bag trap captured a greater number of individuals than the bamboo and fabric traps, but its captures were similar to those of sack trap; captures were similar in bamboo, sack, and fabric traps. When captured individuals were analyzed by stage of development, no significant differences between types of traps were detected for captured adults. The number of individuals captured in the traps showed a similar trend to that counted in nocturnal sampling. A significant positive relationship was detected between numbers of adults captured and the damage of leaves and fruits. Taylor's Power Law indicates that I. subquadratum individuals were more abundant in some traps than in others. With densities greater than five individuals per trap, a smaller number of bag traps was required to estimate the same population compared with the other types of traps. Sampling procedure that used the bag traps had the lowest cost. This study shows that resource-poor coffee, Coffea arabica L., farmers had accumulated knowledge of I. subquadratum based on unpublished data and experience and that they were capable of applying this knowledge to develop an economical and more suitable technology for their conditions.


Assuntos
Coffea/crescimento & desenvolvimento , Controle de Insetos/instrumentação , Ortópteros , Agricultura/métodos , Animais , Frutas , Controle de Insetos/métodos , México , Doenças das Plantas , Folhas de Planta , Estações do Ano
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