Revista Colombiana de Entomología

Susceptibility of the blowfly, Chrysomya putoria (Diptera: Calliphoridae) to the ethanolic extracts of the medicinal plant Moringa oleifera (Magnoliopsida: Moringaceae)

2024-09-12T11:33:56-05:00

Topical administration of Moringa oleifera leaf and seed ethanolic extracts concentrations (5, 10, 25, 50, 75, and 100 mg/L) were screened for insecticide activities against Chrysomya putoria (Diptera: Calliphoridae). Results showed that all tested leaf and seed extractconcentrations were toxic, delayed post-embryonic larval development, and reduced weight. As for C. putoria mortality, from newly hatched larvae to the adult period, all concentrations showed larvicidal power. However, above 20% of the mortality rate occurred in those treated with both leaf and seed extract concentrations. The ones treated with M. oleifera leaf extract concentrations presented the respective mortality rates: 50 mg/L (23 %), 75 mg/L (29 %), and 100 mg/L (30 %). While those treated with M. oleifera seed extract concentrations, the mortality rate observed was 25 mg/L (20 %), 50 mg/L (27 %), 75 mg/L (30 %), and 100 mg/L (32 %). The medicinal plant M. oleifera leaf and seed extracts proved to be a viable alternative for the population control of the medical veterinary and sanitary important blowfly C. putoria.

Soil arthropod diversity, richness, and abundance in agroecological and conventional cotton production systems in Chaco, Argentina

2024-11-06T18:32:21-05:00

In Argentina, agroecology has grown in last years as a scientific paradigm that seeks to design and evaluate agroecosystems considering sustainability, complexity, and uncertainty. Diversity is a key factor in the design and management of production systems and a necessary component for conservation biological control and the reduction of agrochemicals use. Cotton (Gossypium hirsutum) crop in northern Argentina is usually managed with high load of agrochemicals: agroecological production arises as an alternative. This study evaluated the diversity, richness, and abundance of soil arthropods using pitfall traps in two experimental cotton plots under conventional (CONV) and agroecological management (AE) in Chaco, Argentina. AE system presented higher diversity and richness of predators compared with CONV, even when natural preparations were used for pest control. The phytophagous arthropods showed higher diversity and richness in CONV, even when pyrethroid insecticides were applied for pest control and preventively. The abundance in AE was lower for predators and higher for phytophagous arthropods. Agroecological production of cotton can be a tool that favors conservative biological control and an alternative for areas where protecting the health of farmers and the ecosystem is a priority.

Effect of pesticides on Beauveria bassiana and gut microbiota used in biorational methods for the control of Anastrepha obliqua (Diptera: Tephritidae)

2024-12-12T16:53:01-05:00

The implementation of microorganism-based control methods aims to ameliorate the harm caused by pests while simultaneously reducing the unwanted effects caused by synthetic pesticides. However, the interaction between biorational and conventional methods might cause a reciprocal reduction in the efficacy of both methods. Some studies report that pesticides may cause reductions in the pathogenicity of Beauveria bassiana strains and changes in the gut microbiome of some insect species. This is important because B. bassiana is used for fruit fly control, and gut microbiome is known to influence the quality of males reared for autocidal control. The aim of this work was to analyze the toxicity of the herbicide glyphosate and some insecticides on microorganisms used in the control of the fruit fly, Anastrepha obliqua: (1) the entomopathogenic fungus Beauveria bassiana, and (2) the gut microbiome of males of A. obliqua. The results showed that none of the pesticides caused acute toxicity on the evaluated microorganisms. Even though these results suggest that integrating these microorganisms under the current usage of the evaluated pesticides here is feasible, it is relevant to acknowledge that many other environmental variables might be involved. Therefore, field studies are required to complement the findings of this study.

Potential distribution of eight species of Scolytinae and Platypodinae beetles (Coleoptera: Curculionidae) collected in native avocado orchards of Nuevo Leon, Mexico

2024-11-19T19:16:55-05:00

The subfamilies Scolytinae and Platypodinae (Coleoptera: Curculionidae) include bark and ambrosial beetles considered threats in natural ecosystems and agricultural and forest crops due to their damage's ecological and economic impact. The distribution, population dynamics and diversity of the beetle species are affected by environmental factors, and ecosystem fragmentation. Based on the capture of eight beetle species from these subfamilies collected with multi-funnel tramps baited with ethanol in avocado orchards of Aramberri, Nuevo Leon, Mexico, was projected its potential geographic distribution in Mexico using the Maxent v.3.4.4 software. The identification of the captured beetles was done with taxonomic keys; a database was created with records of its presence in regions of Mexico, to model its distribution considering the climatic variables of greatest influence. The potential distribution maps generated, allow the prediction of these species in regions with optimal climatological conditions for their establishment; this information can be used to expand sampling areas, and implement preventive strategies against introducing exotic species. Araptus schwarzi, Monarthrum gracilior, Xyleborinus gracilis and Xyleborus horridus are new records of Scolytinae subfamily species to Nuevo Leon. Corthylus flagellifer, Euplatypus parallelus, Xyleborus ferrugineus, and Xyleborus volvulus are ambrosia beetle species that should be closely monitored in Mexico since they can be potential sources of dissemination of their symbiont phytopathogenic fungi.

Selection of strawberry genotypes resistant to the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae) using micropropagated plants

2024-12-09T18:56:52-05:00

The two-spotted spider mite, Tetranichus urticae (Acari: Tetranychidae) is the main strawberry pest in the states of Michoacán and Guanajuato, Mexico. Its management depends mainly on the application of synthetic acaricides, where farmers in Guanajuato make at least 10 applications of acaricide products per season. With the objectives of identifying strawberry genotypes resistant to the mite and testing an infestation technique in micropropagated plants, 48 clones were evaluated, which included foreign varieties and advanced strawberry selections from the INIFAP Product System Genetic Improvement Program. Based on an arbitrary scale from 0 to 10, where 0 was no spiders and 10 a high population, the 48 clones were classified into the following five categories. Extremely resistant: 'Florida Belle', 'Sequoia' 'Fairfax', 98,32, 08,492, F. vesca clone Guanajuato and UC-4; Resistant: 'Capitola', 'Dabreak', 'Solana', '92,1E6', '07,168', '10,37', '99,849', '07,4' and '99,139'; Tolerant: 'San Andreas', 'Tioga', 'Festival', 'Cometa', C-15,3', '07,35', '06,76', '00,142', '10,14', '10,25', '99,185', '07,207 ', '10,40' and '07,90'; Susceptible: 'Aromas', 'Albritton', 'Camarosa', 'Buenavista', 'Dover', '08,268', '99,24', '08,453', '02,81', '08,279' and '07,198'; Extremely susceptible: 'Douglas', 'Andana', 'Seascape', '02,11', '01,150', '01,70' and '10,16'. The infestation of micropropagated plants had several advantages: avoiding the use of mite-infested vegetative material in strawberry mite susceptibility studies, allowing good colonization with induced infestation, and facilitating evaluation of a large group of genotypes in a small space over a period of time. short period of time.

Spatial distribution of populations agave weevil Scyphophorus acupunctatus (Coleoptera: Dryophthoridae) in the State of Mexico, Mexico

2024-07-24T17:00:22-05:00

Agave is one of the most representative plant groups in Mexico. Its importance lies in its ecological, cultural, and economic value. However, it faces several limitations, especially pest infestations, one of the most important of which is the agave weevil Scyphohphorus acupunctatus Gyllenhal (Coleoptera: Dryophthoridae), which has acquired importance because it bores the stalks into the interior of the plant, causing lesions that are subsequently infected by fungi and/or bacteria until the plant dies. The objective of this study was to determine the spatial distribution of agave weevil populations in two localities in the municipality of Malinalco using spatial analysis of the distance index, SADIE. The results showed that the Ia and Ja indices of the agave weevil populations present values greater than 1, which indicates an aggregated type spatial distribution in the two plots where the study was carried out. Short-term spatial and temporal stability was also determined with the Im index. Density maps were generated for each sampling in the two plots, with the maps that were elaborated, the infested surface in each plot was calculated, the results show us the distribution of the pest, and the alternatives for sustainable management of this pest are proposed.

Effectiveness of insecticides for the control of Plutella xylostella (L.) (Lepidoptera: Plutellidae) and mortality of the parasitoid Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae) on brassicaceous plants

2024-12-02T18:39:05-05:00

Crop production of brassicaceous crops in Mexico are affected by the attack of the diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae). An inadequate application of insecticides indirectly affects the main parasitoid of this pest, the wasp Diadegma insulare (Cresson) (Hymenoptera: Ichneumonidae). Eight insecticide treatments and one control were evaluated using a completely randomized design with four replications. The objective of this research was to evaluate, under laboratory conditions, three organic insecticides, five synthetic insecticides and a control, to determine their effectiveness in controlling P. xylostella and its effect on the mortality of the parasitoid D. insulare. Broccoli leaf immersion method in solution with insecticides was used. Pyridalil caused the highest mortality (100 %) in the third-instar larval stage of P. xylostella at 48 h after application and mild to moderate mortality (categories 1 and 2 of the IOBC) to D. insulare at 72 hours; Naled obtained 100 % mortality in the larva and adult of P. xylostella, but also caused 100 % mortality in the parasitoid 24 h after treatment. Among the organic insecticides, Pyrethrin produced the highest mortality in P. xylostella larvae (60 %) at 72 h in the two doses used and caused a mortality of 10 % in D. insulare. Pyridalil and Emamectin Benzoate insecticides showed high effectiveness for the control of the insect-pest and had low impact on the parasitoid.

New record of Padaeus trivittatus (Hemiptera: Pentatomidae) as a predator of the monarch butterfly Danaus plexippus (Lepidoptera: Nymphalidae) in Central Mexico

2024-09-12T11:33:53-05:00

Lepidoptera includes agricultural pests, pollinators, and bioindicators of the environment quality. Adults of Danaus plexippus (Lepidoptera: Nymphalidae) are preyed by some birds, and rodents; in its immature stages are preyed mainly by arthropod predators. Arthropod predation is a factor that decreases the survival of D. plexippus. Two adult males of Padaeus trivittatus (Hemiptera: Pentatomidae) were found preying on D. plexippus for the first time.

Una aproximación a la entomofauna en agroecosistemas de Salvatierra, Guanajuato, México

2024-12-16T21:04:03-05:00

The municipality of Salvatierra, in Guanajuato, Mexico, develops an agricultural activity of national and regional importance. However, despite this, there needs to be more information on ecologically and economically important faunal groups, such as insects. Therefore, the objective of this study was to have an approximation of the entomofauna in four crops: sorghum, alfalfa, maize, and beans, as well as their composition and the characterization of the functional groups of insects in a dry seasonal tropical environment of the municipality of Salvatierra. The entomofauna for the four crops is composed of nine orders: Coleoptera, Diptera, Dermaptera, Hemiptera, Hymenoptera, Lepidoptera, Mantodea, Neuroptera, and Orthoptera, and 53 families. The highest Simpson Wealth Index value was for alfalfa (0.91) and the lowest for beans (0.84). On the other hand, in terms of its structure and composition, the entomofauna is represented by eight functional groups: Herbivores = H, Predators = D, Parasitoids = PAR, Pollinators = POL, Vectors = V, Decomposers = DES, Xylophages = XIL, and Generalists = G. Phytophagous insects (pests), predators and parasitoids are the most common and abundant in crops. The present work generates new data on the entomofauna present in the agroecosystems of the community of Urireo in the municipality of Salvatierra, Guanajuato state, informing the development of specific studies of demography and ecological interactions between insect-plant and insect-insect.

Mosquito larvicidal and cytotoxic potentials of the different extracts of the aerial part of Blepharis ciliaris (Acanthaceae) against Culex pipiens (Diptera: Culicidae)

2023-11-14T01:56:46-05:00

This study explores the larvicidal potential of a hexane extract from Blepharis ciliaris against Culex pipiens mosquitoes, a known vector of various diseases. The study aimed to find an eco-friendly alternative to chemical insecticides. Promising results were obtained, with the extract showing significant larvicidal activity. The LC50, LC90, and LC95 values against C. pipiens were determined as 125.53, 190.5, and 198.76 µg/mL, respectively. Furthermore, histological observations using a light microscope revealed notable changes in the midgut structure of the treated larvae, including degradation of microvilli, degeneration, and protrusion of epithelial cells and peritrophic membrane, loss of nuclei, and irregular microvilli. These findings suggest that the hexane extract from B. ciliaris has the potential as a natural larvicidal agent against C. pipiens mosquitoes. The MTT assay results indicate that the tested extracts did not exhibit cytotoxic effects on Huh-7 cells, and no morphological changes were observed under light microscopy. The findings of this study suggest that B. ciliaris contains bioactive compounds that could serve as potential bio-larvicides for controlling C. pipiens vectors. Further research should be conducted to assess the efficacy of using this botanical insecticide in small-scale field trials to develop environmentally safe interventions for controlling C. pipiens populations.