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The Arecaceae family has a worldwide distribution, especially in tropical and subtropical regions. We sequenced the chloroplast genomes of Acrocomia intumescens and A. totai, widely used in the food and energy industries; Bactris gasipaes, important for palm heart; Copernicia alba and C. prunifera, worldwide known for wax utilization; and Syagrus romanzoffiana, of great ornamental potential. Copernicia spp. showed the largest chloroplast genomes (C. prunifera: 157,323 bp and C. alba: 157,192 bp), while S. romanzoffiana and B. gasipaes var. gasipaes presented the smallest (155,078 bp and 155,604 bp). Structurally, great synteny was detected among palms. Conservation was also observed in the distribution of single sequence repeats (SSR). Copernicia spp. presented less dispersed repeats, without occurrence in the small single copy (SSC). All RNA editing sites were C (cytidine) to U (uridine) conversions. Overall, closely phylogenetically related species shared more sites. Almost all nodes of the phylogenetic analysis showed a posterior probability (PP) of 1.0, reaffirming the close relationship between Acrocomia species. These results elucidate the conservation among palm chloroplast genomes, but point to subtle structural changes, providing support for the evolutionary dynamics of the Arecaceae family., (© 2023. The Author(s).)

The most used pesticides have neurotoxic action on the neurotransmitter system of target and non-targeted insects, such as honeybees. However, honeybees have foremost importance worldwide, which has encouraged the development of tools to evaluate the action of specific pesticide molecules on their nervous system, providing accurate data on damage to their brain. In this sense, our study aimed to optimize in vitro honeybee nervous tissue culture to assess pesticide risks. To this end, six forager honeybee brains were dissected and transferred to different combinations of Leibovitz-15 (L-15) culture medium supplemented with Fetal Bovine Serum (FBS), Hank's Balanced Salt Solution (HBSS), and Insect Medium Supplement (IMS). Nervous tissues were collected after different incubation times (1, 6, 12, and 24 h) for morphology and Kenyon cell analyses. Our results showed that L-15 medium supplemented with HBSS and with HBSS plus FBS were the best media for culturing honey nervous tissue for 24 h, as they resulted in less tissue spacing and cell disarrangement. Therefore, they may be assessed in future ecotoxicological tests., Competing Interests: Declaration of Competing Interest, (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Bees are important pollinators that help to maintain the biodiversity of wild and cultivated plants. However, the increased and inappropriate use of agrochemicals has caused an imbalance in the populations of these insects visiting flowers for pollen and nectar collection. Therefore, new research methods for understanding the mechanisms of action of pesticides and their impacts on the brains of bees, such as neurotoxicity and cellular changes, in response to different active characteristics and dosages of insecticides are necessary. Thus, with the aim of developing tests with greater specificity at the level of cells or tissues, this study sought to standardize a method for the in vitro culture of the nervous tissue of Apis mellifera. For this purpose, the brains of six foragers bees were transferred to three different insect cell culture media and it supplementation with 10% foetal bovine serum (FBS): Grace, Schneider, Leibovitz, Grace + FBS, Schneider + FBS and Leibovitz + FBS media for each collection time. Nervous tissue was collected after 1, 6, 12 and 24 h of incubation in a humidified CO 2 incubator at 32 °C, and histological sections of the organs were analysed. The results showed that Leibovitz medium and Leibovitz medium + serum are potential culture media for the cultivation of nervous tissue, since they resulted in less tissue spacing and tissue disarrangement. Therefore, additional supplements are necessary to obtain an ideal medium for the cultivation of A.mellifera nervous tissue., (Copyright © 2019 Elsevier Inc. All rights reserved.)