The prickly pear cactus, Opuntia ficus-indica (L.) Miller, is the most economically important Cactaceae species worldwide. It thrives in arid and semiarid agricultural lands with minimal inputs, providing benefits such as livestock fodder, fruit, and vegetable production. The South American cactus moth, Cactoblastis cactorum (Berg), represents the most important insect pest of prickly pear crops. This study aimed to evaluate the impact of C. cactorum feeding on O. ficus-indica plants in a plantation in northwestern Argentina. Fruit production, fruit attributes, and plant size were evaluated under increasing C. cactorum pest densities in a manipulative 3-yr-long experiment (2018 to 2020). In the 2019 harvest, the increase in the pest density significantly reduced the number of fruits produced/plant. Plants with the highest pest density produced 60% fewer fruits than pest-free plants. In the 2020 harvest, the reduction was marginal. Fruit and pulp weights significantly declined with increasing C. cactorum densities in both years. No effect occurred on plant size or fruit sweetness. This was the first effort to measure the magnitude of the impact of C. cactorum on a cactus crop species and provides crucial information for prickly pear fruit producers. This information is helpful to implement more effective preventive and control measures to protect producers’ investment and ensure a profitable harvest. Further studies in younger plantations and other areas will help develop an economic damage threshold level to support Integrated Pest Management decisions to limit C. cactorum’s impact.

1. Describing the genetic structure and diversity of invasive insect pest populations is essential to better understand a species' invasion history and success throughout its distribution range. Tuta absoluta (Meyrick) (Lepidoptera, Gelechiidae) is a destructive pest of tomato and many other solanaceous crops, with very high economic impacts. Its invasion threatens food security in a large part of the globe, in areas such as sub-Saharan Africa where the agricultural resilience has already been weakened by rapid human-induced changes due in particular to population growth, increased trade and global change. 2. This work aimed to investigate the diversity and genetic structure of 60 populations of T. absoluta using microsatellite markers, with a particular focus on sub-Saharan Africa. 3. Our results revealed distinct differentiation and diversity patterns between T. absoluta native versus invaded areas, and high genetic homogeneity among the African populations sampled. However, for the first time, two weakly differentiated but distinct genetic clusters in Africa were identified. 4. The results suggest few introduction events of the species in Africa or multiple introductions from genetically close areas, significant gene flow between outbreaks and seem to indicate the existence of two distinct clusters in Africa. This new data enable us to formulate hypotheses on the species' invasion patterns and the dynamics of its invasive populations. 5. These hypotheses must be verified with more extensive sampling over the whole range of T. absoluta, especially in its presumed native area.

The cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae), is a major agricultural pest affecting crops like cotton, maize, tomatoes, and wheat across southern Europe, Africa, the Middle East, and western Asia. Whole genome analyses have revealed adaptive evolution in chemosensation and detoxification genes in S. littoralis. However, the extent of intraspecific diversity influenced by recent adaptive evolutionary forces remains unclear. In this study, we conducted a population genomics analysis using 31 S. littoralis individuals from sub-Saharan Africa, northern Africa, and southern Europe to assess the existence of intraspecific population divergence and identify the underlying evolutionary forces. We show whole genome differentiation between populations based on geographic origin from the analyzed samples. Phylogenetic analyses indicate that sub-Saharan and southern European populations share a common ancestor, distinct from several northern African populations. FST and dXY statistics along the chromosomes reveal loci with restricted gene flow among populations. These loci are associated with population-specific selective sweeps, indicating the role of divergent natural selection in limiting gene flow. Notably, these loci are enriched with detoxification genes, including cytochrome P450, multidrug resistance, and xanthine dehydrogenase genes, all of which are potentially associated with detoxification. These results demonstrate that divergent selection limits gene flow among geographically distinct populations with the possibility of the involvement of detoxification as a key trait. We argue that this genetic heterogeneity can be considered in pest monitoring and management, as strategies tailored to specific populations may not be relevant for others.

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1. This review provides a synthesis of the available knowledge on Carmenta foraseminis, an emerging cocoa pest in northern South America. 2. This moth was first described in 1995 in Panama, and its proliferation across the Amazon basin is currently threatening the production of cocoa in the region and may endanger the sector's sustainability. Hence, it is important to further draw the attention of researchers towards this emerging pest. The larvae of this lepidopteran burrow within the pod and feed on beans and their pulp, causing important losses. 3. We present a critical synthesis of the knowledge on C. foraseminis (biology, geographic distribution, phylogenetic status, ecology), to identify the cause of its emergence and key points for its control. 4. We also describe similarities to another lepidopteran, the Cocoa Pod Borer (CPB) Conopomorpha cramerella, which is the main pest of cocoa in Asia, especially on the way it is controlled and eventual lessons and recommendations that can be drawn from the situation in Asia to better understand and manage cocoa pod infestation in the Amazon basin. 5. Additionally, we propose further research themes to be explored for Carmenta foraseminis that will help in the development of efficient management practices.

Swollen Shoot is a viral disease affecting cocoa trees, transmitted by several species of mealybugs (Insecta, Hemiptera, Sternorrhyncha, Pseudococcidae). These insects maintain trophobiotic relationships with a complex and species-rich assemblage of ants protecting them and natural enemies controlling their populations. Here, we provide a curated DNA barcode database to characterise this insect community. Systematic observation of 7,500 cocoa trees was conducted, coupled with the collection of mealybug colonies and associated insect communities (parasitoids, predators and ants). Natural enemies were reared from mealybug colonies collected from 1,430 cocoa trees. Specimens were identified morphologically and sequenced for fragments of the standard DNA barcode region of the COI. We recovered 17 species of mealybugs from the family Pseudococcidae. Amongst these species, eight are new to the Ivorian cocoa orchard: Dysmicoccus neobrevipes Beardsley, Ferrisia dasylirii (Cockerell), Maconellicoccus ugandae (Laing), Paracoccus marginatus Williams & Granara de Willink, Phenacoccus solenopsis Tinsley, Planococcus minor (Maskell), Pseudococcus concavocerarii James and Pseudococcus occiduus De Lotto. Three of these species were identified for the first time in cocoa orchards in Africa: D. neobrevipes, Fe. dasylirii and Ph. solenopsis. A total of 54 ant species were identified and represented the first record of these species associated with mealybug colonies in cocoa in Côte d’Ivoire. Amongst the species associated with the mealybugs, 22 primary parasitoids, eight hyperparasitoids, 11 ladybirds beetles (Coccinellidae), seven gall midges (Cecidomyidae), one predatory lepidopteran species and four spider species were identified. Nine species of mealybugs parasitoids are newly recorded in the African cocoa orchards: Acerophagus aff. dysmicocci, Aloencyrtus sp., Anagyrus kamali, Anagyrus aff. pseudococci, Aenasius advena, Clausenia aff. corrugata, Gyranusoidea aff. tebygi, Zaplatycerus aff. natalensis (Encyrtidae) and Coccophagus pulvinariae (Aphelinidae) and one hyperparasitoid, Pachyneuron muscarum (Pteromalidae). For Côte d’Ivoire in particular, besides the previously mentioned nine parasitoids and one hyperparasitoid, five additional species are recorded for the first time, including four primary parasitoids, Blepyrus insularis (Encyrtidae), Clausenia corrugata (Encyrtidae), Clausenia sp. (Encyrtidae), and Coccidoctonus pseudococci (Encyrtidae) and one hyperparasitoid, Cheiloneurus cyanonotus (Encyrtidae). These results significantly enhance the knowledge of the diversity of the entomofauna associated with Swollen Shoot disease and pave the way for developing control methods based on the natural regulation of its mealybug (Pseudococcidae) vectors.

La dénomination de "veau rosé" est diversement définie et peu étudiée en France. Cette production est bien adaptée aux races locales, comme dans le cas de la Maraîchine. Les performances d’abattage des veaux rosés extraites d’une base de données de 119 veaux obtenue entre 2009 à 2023 sur l’unité expérimentale INRAE de Saint-Laurent-de-la-Prée sont décrites. Les caractéristiques biochimiques et métaboliques ainsi que les qualités sensorielles et nutritionnelles des viandes ont été analysées sur échantillon de 30 veaux rosés (15 élevés au pis et à l’herbe (pâture et/ou foin) (régime H) et 15 veaux élevés au pis et complémentés aux concentrés (régime C)) issus de 8 élevages différents. Les veaux ont un poids vif moyen de 219 kg, un poids carcasse de 128 kg et un poids de viande de 90 kg. Les rendements carcasse sont en moyenne de 59 % et les rendements viande de 70 %. La viande de veau rosée est pauvre en lipides (1,3g/100g de tissu). Elle présente une proportion d’AGPI élevée proche de 20% et un rapport AGPI n-6/n-3 proche de 2. Le régime alimentaire des veaux a des impacts significatifs sur la qualité de la viande. Le régime H impacte la conformation des carcasses, la couleur de la viande, la teneur en fer (+ 24%) et la tendreté. Il augmente de 53% la proportion de fibres lentes et oxydo-glycolytiques. Certaines teneurs en acides gras d’intérêt, en vitamine B2 et des indicateurs santé sont également augmentées. Enfin le régime H entraine également un double enrichissement en antioxydants endogènes ou exogènes et une diminution des teneurs en vitamines B3 et B6.