Search

Simple Summary: The South American fruit fly Anastrepha fraterculus (Wiedmann) is found from northern Mexico to northern Argentina, where it causes damage to many different wild and cultivated fruits. It is a not a single species, but a complex of practically identical species. Eight morphological types (morphotypes) have been identified. To facilitate the identification of the species, alternative, non-morphological methods, such as those based on genome sequences, are necessary. The sterile insect technique is an efficient method used to combat these pests, which involves the release of many sterile male insects into the wild. Mass-reared sterile field-released males mate with females, which lay inviable eggs, thereby reducing the population. This approach is only successful when the released males are sexually compatible with the females of the target population. Hence, accurate identification is necessary for its success. We evaluated the use of the internal transcribed spacer 2 (ITS2) sequence for discriminating members of the A. fraterculus cryptic species complex and a related species, Anastrepha schultzi Blanchard. The ITS2 sequence successfully discriminated between different morphotypes and provides a basis for the development of keys for discrimination of the species within the complex. ITS2 also represents an important marker for the poorly studied species A. schultzi. The South American fruit fly Anastrepha fraterculus (Wiedmann) has a vast range extending from northern Mexico, through Central America, to South America where it is an extremely polyphagous pest of wild and cultivated fruits. It is a complex of cryptic species currently composed of eight recognised morphotypes: "Mexican", "Venezuelan", "Andean", "Peruvian", "Ecuadorian", and the three Brazilian morphotypes "Brazilian-1", "Brazilian-2", and "Brazilian-3". Molecular markers that can identify the member species of the complex are crucial for the implementation of effective pest control measures, such as the sterile insect technique. The object of this study was to evaluate the use of the internal transcribed spacer 2 (ITS2) sequence for discriminating several members of the A. fraterculus cryptic species complex (Mexican, Peruvian, and Brazilian-1) and a related species, Anastrepha schultzi Blanchard. The analysis highlighted significant genetic differentiation between the evaluated morphotypes, allowed their discrimination within the A. fraterculus cryptic species complex, and provided new insights into their genetic relationships. The ITS2 marker provides a basis for the development of taxonomic keys for the discrimination of the cryptic taxa within the A. fraterculus cryptic species complex. ITS2 also represents an important marker for the poorly studied species A. schultzi. [ABSTRACT FROM AUTHOR]

Simple Summary: The Mediterranean fly (Medfly), Ceratitis capitata, is considered one of the world's most destructive fruit pests, as it can attack commercially important fruit, thus causing considerable economic damages, estimated to be more than 2 billion dollars annually. The yield reductions are mainly due to the damage incurred when larvae feed directly on the pulp, inducing the premature fruit drop. Additionally, oviposition holes facilitate secondary fungal and bacterial infections, further reducing the yields. Integrated pest management (IPM) strategies for medfly control are highly dependent on the use of insecticides, which, however, pose environmental concerns. Alternative strategies include the Sterile Insect Technique (SIT), which aims to eliminate or suppress pest insects without using pesticides. Lately, the medfly microbiota has been explored to develop new control strategies for insect pests and insect vectors. Here, we report the characterization of the microbial communities associated with selected organs of three different populations of C. capitata to identify possible candidates for a Symbiotic Control approach. Our findings provide new knowledge about the microbiota associated with C. capitata and stress the characterization of microbial symbionts as possible tools for a Symbiotic Control approach to implementing the pest management programs. Ceratitis capitata (Diptera: Tephritidae) is responsible for extensive damage in agriculture with important economic losses. Several strategies have been proposed to control this insect pest including insecticides and the Sterile Insect Technique. Traditional control methods should be implemented by innovative tools, among which those based on insect symbionts seem very promising. Our study aimed to investigate, through the 16S Miseq analysis, the microbial communities associated with selected organs in three different medfly populations to identify possible candidates to develop symbiont-based control approaches. Our results confirm that Klebsiella and Providencia are the dominant bacteria in guts, while a more diversified microbial community has been detected in reproductive organs. Concertedly, we revealed for the first time the presence of Chroococcidiopsis and Propionibacterium as stable components of the medfly's microbiota. Additionally, in the reproductive organs, we detected Asaia, a bacterium already proposed as a tool in the Symbiotic Control of Vector-Borne Diseases. A strain of Asaia, genetically modified to produce a green fluorescent protein, was used to ascertain the ability of Asaia to colonize specific organs of C. capitata. Our study lays the foundation for the development of control methods for C. capitata based on the use of symbiont bacteria. [ABSTRACT FROM AUTHOR]

Simple Summary: Many studies have been performed to assess the effects of chemical compounds on mosquito behaviour. These studies almost exclusively involve only female mosquitoes as they can transmit disease pathogens, or at least, cause biting nuisance. Few studies have considered male mosquitoes. The identification of chemical substances that attract males can be very useful for trapping purposes, especially for monitoring the makeup of the male population during control programmes, such as those involving the release of sterile male mosquitoes. Twenty-eight chemical compounds from different chemical classes were evaluated using a dual-port olfactometer assay with at least three serial hexane dilutions against a hexane control. The compounds included known animal, plant and fungal volatiles, and the components of a putative Aedes aegypti pheromone. Many of the compounds were repellent for male mosquitoes, especially at the highest concentration. One compound, decanoic acid, acted as an attractant for males at an intermediate concentration. Decanoic acid did not elicit a significant response from female mosquitoes. The Asian tiger mosquito, Aedes albopictus, has become one of the most important invasive vectors for disease pathogens such as the viruses that cause chikungunya and dengue. Given the medical importance of this disease vector, a number of control programmes involving the use of the sterile insect technique (SIT) have been proposed. The identification of chemical compounds that attract males can be very useful for trapping purposes, especially for monitoring the makeup of the male population during control programmes, such as those involving the use of the SIT. Twenty-eight chemical compounds from different chemical classes were evaluated using a dual-port olfactometer assay. The compounds included known animal, fungal and plant host volatiles, and components of a putative Aedes aegypti pheromone. Many of the compounds were repellent for male mosquitoes, especially at the highest concentration. One compound, decanoic acid, acted as an attractant for males at an intermediate concentration. Decanoic acid did not elicit a significant response from female mosquitoes. [ABSTRACT FROM AUTHOR]