Elia Diego-García

Proper diet formulation is crucial for the successful mass‐rearing of tephritid fly larvae to ensure that they receive adequate nutrition. Nutrient acquisition can vary significantly across different developmental stages due to adaptations to specific environments where access to nutrients is limited by diet composition. It is imperative to determine the metabolic relationship between the fat body and the hemolymph in order to understand how insects respond to changes in their food environments. The main objective of this study was to investigate how the food environment affects the metabolism of Mexican fruit fly larvae, focusing on nutrient accumulation, gene expression, and response to oxidative stress in the hemolymph and fat body. The study employed a two‐way experimental design with three environments for larval development: corncob powder and coconut fibre as artificial diets and Mexican apple fruit ( Casimiroa edulis ) (Sapindales: Rutaceae) as a wild host, and two tissues (hemolymph and fat body). The results showed that hemolymph provides valuable information on oxidative stress levels, while the fat body serves as an indicator of protein and glycogen accumulation. Additionally, Lsp‐2 expression was identified as a means to determine the developmental stage of fruit fly larvae. A particularly significant contribution of this study is that dietary factors and the food environment can influence the size and shape of lipid droplets, thereby affecting the structure and functionality of the fat body. This information holds practical importance as these processes can impact the overall quality and sexual competitiveness of mass‐reared insects used for the SIT.

Members of the genus Cupiennius Simon, 1891 are categorized as wandering spiders and are part of the family Trechaleidae. The genomics and proteomics of Cupiennius spiders from North America remain uncharacterized. The present study explores for the first time molecular data from the endemic species Cupiennius chiapanensis Medina, 2006, and also presents new data for Cupiennius salei (Keyserling, 1878), both collected in southern Mexico.

The three major macronutrients – proteins (P), carbohydrates (C), and lipids (L) – constitute the fundamental nutrient niche. In order to meet their nutritional requirements, organisms need to assess their nutritional state, select suitable foods, and regulate the amount of food eaten. The objective of this study was to determine whether larval nutrition could have a differential effect on female and male survival and fecundity by manipulating the P:C:L ratios in diet environments. We manipulated food availability during the larval stages, subjecting the larvae to food regimes with different P:C:L ratios. Upon adult emergence, we examined the fecundity, fertility, survival, and longevity of the various larval nutrition treatments. We then assessed the reproductive performance (fecundity and egg hatching) under an ad libitum food regime. We found that the concentration of macronutrients in the larval hemolymph indicates that the P:C:L ratio in the larval diet affects the assignment of macronutrients, and this effect is carried over to males and females differently. A larval diet with high carbohydrate content affects the carryover of macronutrients and male and female fitness. According to the life‐history traits, an adult that emerged from a larva with high lipid content in the hemolymph could suggest better health status. Insects with high cold tolerance have high body lipids content. Interactions between lipids, carbohydrates, and proteins suggest that their relative ratios must be taken into consideration in the design and improvement of artificial diets.

Phonotimpus pennimani (Araneae, Phrurolithidae) is a small-sized (3-5 mm) spider endemic to the Tacaná volcano in Chiapas, Mexico, where it is found in soil litter of cloud forests and coffee plantations. Its venom composition has so far not been investigated, partly because it is not a species of medical significance. However, it does have an important impact on the arthropod populations of its natural habitat. Specimens were collected in Southeastern Mexico (Chiapas) and identified taxonomically by morphological characteristics. A partial sequence from the mitochondrial gene coxI was amplified. Sequencing on the Illumina platform of a transcriptome library constructed from 12 adult specimens revealed 25 toxin or toxin-like genes. Transcripts were validated (RT-qPCR) by assessing the differential expression of the toxin-like PpenTox1 transcript and normalising with housekeeping genes. Analysis of the coxI-gene revealed a similarity to other species of the family Phrurolithidae. Transcriptome analysis also revealed similarity with venom components of species from the families Ctenidae, Lycosidae, and Sicariidae. Expression of the toxin-like PpenTox1 gene was different for each developmental stage (juvenile or adult) and also for both sexes (female or male). Additionally, a partial sequence was obtained for the toxin-like PpenTox1 from DNA. Data from the amplification of the mitochondrial coxI gene confirmed that P. pennimani belongs to the family Phrurolithidae. New genes and transcripts coding for venom components were identified.

The advent of omics has expanded our knowledge of microbial ecology behind Mezcal, a fermented spirit made from the juices of cooked Agave plants (Agave spp., Asparagaceae). Mezcal has been produced in Mexico for over 200 years, however, has been in high demand since its discovery by international markets in the last decade. Mezcal is appreciated for its diverse and complex sensory profile, which is tied to the geographic and environmental diversity of the different Mezcal-producing regions. This regional typicity is brought about by spontaneous fermentation consortia that act in loosely controlled artisanal fermentation processes. Previous works have mainly concentrated on microorganisms involved in the biosynthesis of alcohol and other volatile compounds, or from a different perspective, on culturable microorganisms (mainly yeasts) influencing the taste profile. Attention has been aimed at the richness of microbial populations in point events or under laboratory conditions, which leaves much of the biological richness out of account. Omics techniques have become powerful tools for characterizing the composition of autochthonous fermentation microbiota, regional or endemic features, and ecological processes that determine the dynamics of Mezcal fermentation. The analyses of genetic material, proteins, and metabolites allow disentangling the biological complexity of Mezcal production. This review presents the reader with an up-to-date overview of publications that discuss microbial communities in Mezcal fermentation, metabolic pathways regulated by microbial interactions, and the application of omics to characterize the spontaneous fermenting microbiota conformation and dynamics considering the subjacent ecological processes.

La supresión de moléculas de ácido ribonucleico mensajero (ARNm) mediante ARN interferente (ARNi) se ha propuesto como método de control de insectos plagas. El ARNi impide el desarrollo morfológico y funcional de los insectos y se considera altamente específico. En este estudio se buscaron receptores de insulina (InR) en Brevicoryne brassicae L. (Hemiptera: Aphididae) a partir del ARNm de pulgones, como primer paso para el diseño posterior de ARNi dirigido a la supresión de InR. A partir del ácido desoxirribonucleico complementario (ADNc) y mediante PCR anidada, se amplificó la región correspondiente a InR con dos pares de cebadores diseñados para Nilaparvata lugens (Homoptera: Delphacidae). No se logró identificar InR, en su lugar se predice la presencia de la proteína receptora Dip2A de unión a folistatina (FS) debido a que comparten regiones proteicas similares con los InR, involucradas en la traducción de señales en los insectos. Se sugiere continuar con la búsqueda de InR específicos para el pulgón, así como posibles cebadores para regiones de Dip2A, para lograr un ARNi altamente específico. Suppression of messenger ribonucleic acid (mRNA) molecules by RNA interference (RNAi) has been proposed as a method for controlling insect pests. RNAi impedes the morphological and functional development of insects and is considered highly specific. In this study, insulin receptors (InR) were searched for in Brevicoryne brassicae L. (Hemiptera: Aphididae) from aphid mRNA, as a first step for further design of RNAi targeting InR suppression. From complementary deoxyribonucleic acid (cDNA) and by means of nested PCR, the region corresponding to InR was amplified with two pairs of primers designed for Nilapavata lugens (Homoptera: Delphacidae). InRs could not be identified. However, the presence of the follistatin-binding receptor protein Dip2A (FS) was predicted from the regions of similarity with the InRs that are involved in signal translation in insects. We recommend continuing the search for aphid specific InRs, as well as possible primers for Dip2A regions, to identify a highly specific RNAi.

Although the bulking agent is categorized as ‘inert’, it could modify protein bioavailability and nutritional quality. In this study, the main goal was to determine if the bulking agent modified the protein:carbohydrate (P:C) ratio and bioconversion from diet biomass to larval biomass of Anastrepha ludens. The diet was altered only by modifying the type of bulking agent (corncob powder, coconut fiber, carrot fiber, oatmeal) added without changing the composition and concentration of the other components in the formulation. This allowed reclassification of the food matrices according to P:C ratios of 1:30, 1:35, 1:64, and 1:93. A food matrix with a high P:C ratio promoted a high protein and carbohydrate content in the larval hemolymph and immediately influenced the life-history traits of the larva or delayed them in the adult. The present study indicated a positive relationship between the P:G+T (glucose+trehalose) ratio in the larval hemolymph and the P:C ratio in the larval diet. Our results highlight the importance of including the optimum and real P:C ratio in whole fresh larval diets, since considering only the theoretical concentration of the formulation is not enough to understand the variation in key life-history traits. In addition, the bioconversion index should be included as an indicator of the efficacy of larval diets for mass rearing insects. A diet with high cost-effectiveness should be evaluated by taking into account flying flies as the end product of the mass rearing process to enhance operational SIT programs.