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- O contributo do GO FruitFlyProtect para melhorar a proteção contra a drosófila-de-asa-manchadaPublication . Figueiredo, Elisabete; Godinho, Maria do Céu; Simões, Miguel; Alexandre, Paulo; Mendonça, Tomás; Oliveira, Mário; Mateus, Célia; Valério, Elsa; Mexia, AntónioApresentam-se os resultados obtidos no GO FruitFlyProtect relativos às capturas de Drosophila suzukii em armadilhas (dispositivo e isco), para estimativa do risco ou para captura em massa. Utilizaram-se os dispositivos das marcas Econex, Koppert, Biobest, com o isco respetivo, e garrafa PET e dispositivo “Lasa”, construídos artesanalmente e iscados com composto de vinagre da empresa Mendes & Gonçalves Lda. Na armadilha “Lasa” usou-se ainda fermento de padeiro como isco adicional. Mais tarde, incluiu-se o dispositivo da Biobest e respectivo isco. A placa vermelha iscada da Econex nunca capturou D. suzukii. A garrafa PET apresentou capturas mais elevadas e a armadilha Koppert a maior especificidade. Expõem-se problemas detetados na identificação de D. suzukii, nomeadamente a possibilidade de confusão entre as formas de inverno desta espécie e as drosófilas do grupo D. obscura. Avaliou-se, também, a eficácia de três espécies de nemátodes entomopatogénicos no combate a D. suzukii: Steinernema carpocapsae, S. feltiae e Heterorhabditis bacteriophora, tendo S. carpocapsae induzido maior mortalidade que S. feltiae em placa de Petri. Não ocorreu mortalidade em pupas.
- Drosophila suzukii: conhecer para melhor combaterPublication . Mateus, Célia; Godinho, Maria do Céu; Figueiredo, ElisabeteDrosophila suzukii (Matsumura) ou “drosófila-da-asa-manchada” é uma espécie que dispensa apresentações, devido aos prejuízos que tem vindo a causar em várias culturas, principalmente nas de pequenos frutos. Tal como aconteceu em 2016, no último Colóquio Nacional de Produção de Pequenos Frutos, faz-se aqui uma atualização do conhecimento sobre esta espécie, através da análise de trabalhos de investigação realizados entre 2016 e 2021. O objetivo é conhecermos melhor a praga e as mais recentes propostas para monitorização e controlo. Pretende-se contribuir para uma produção sustentável de pequenos frutos em quantidade e qualidade e ir ao encontro do interesse dos produtores e consumidores.
- Proteção biológica contra as principais pragas na cultura de tomate protegido no OestePublication . Rodrigues, S.; Godinho, M.C.; Valério, E.; Abraços-Duarte, G.; Figueiredo, E.
- Functional response and predation rate of Dicyphus cerastii Wagner (Hemiptera: Miridae)Publication . Abraços-Duarte, Gonçalo; Ramos, Susana; Valente, Fernanda; Borges da Silva, Elsa; Figueiredo, ElisabeteDicyphine mirids are important biological control agents (BCAs) in horticultural crops. Dicyphus cerastii Wagner can be found in protected tomato crops in Portugal, and has been observed feeding on several tomato pests. However, the predation capacity of this species is poorly studied. In order to investigate the predation capacity of D. cerastii, and how it is affected by prey size and mobility, we evaluated the functional response (FR) and predation rate of female predators on different densities of four prey species: Myzus persicae 1st instar nymphs (large mobile prey), Bemisia tabaci 4th instar nymphs, Ephestia kuehniella eggs (large immobile prey) and Tuta absoluta eggs (small immobile prey). Experiments were performed on tomato leaflets in Petri dish arenas for 24 h. Dicyphus cerastii exhibited type II FR for all prey tested. The predator effectively preyed upon all prey, consuming an average of 88.8 B. tabaci nymphs, 134.4 E. kuehniella eggs, 37.3 M. persicae nymphs and 172.3 T. absoluta eggs. Differences in the FR parameters, attack rate and handling time, suggested that prey size and mobility affected predation capacity. Considering the very high predation rates found for all prey species, D. cerastii proved to be an interesting candidate BCA for tomato crops
- Armadilhas de feromona sexual com luz para captura em massa de Tuta absoluta (Meyrick), sim ou não ?Publication . Matos, Tiago; Figueiredo, Elisabete; Mexia, AntónioIn an assay performed in November 2010, adults captured in sexual pheromone water traps with and without light were counted. In traps with light a part of the insects were sampled for sex identification. Water traps for mass trapping which combined the attractive effect of sexual pheromone and light captured higher levels of Tuta absoluta adults than the traditional ones, with pheromone bait only. However, these traps were unable to capture females of T. absoluta (about 1.1% of the captured adults were females), an expected event due to the light effect. Although capturing higher number of males of T. absoluta, the lack of female captures makes it hard to justify the use of these traps, considering its high cost compared with conventional pheromone water traps.
- Intraguild predation and cannibalism among Dicyphini: Dicyphus cerastii vs. two commercialized speciesPublication . Abraços Duarte, Gonçalo; Caldas, Filipa; Pechirra, Ariadna; Borges da Silva, Elsa; Figueiredo, ElisabeteDicyphine mirids are one of themost important groups of predators on tomato. In theMediterranean region, several species in the genera Dicyphus, Macrolophus, and Nesidiocoris (Hemiptera: Miridae, Bryocorinae, Dicyphini) colonize protected horticultural crops. In Portugal, Nesidiocoris tenuis (Reuter) is increasingly abundant in the mirid species complex of tomato crops and appears to be displacing the native Dicyphus cerastii Wagner. In order to know whether intraguild predation (IGP) can explain the decreasing abundance of D. cerastii, we evaluated predatory interactions between adult females and first instars of D. cerastii vs. N. tenuis but also D. cerastii vs. Macrolophus pygmaeus (Rambur), as this species is also naturally present in horticultural crops in Portugal. Cannibalistic interactions were also tested for the same three species. All experiments were performed under laboratory conditions, in Petri dish arenas, in the presence or absence of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as alternative prey. Predation on both heterospecific and conspecific nymphs occurred only in the absence of alternative food. Intraguild predation was mutual and symmetrical between D. cerastii andM. pygmaeus. However, IGP was asymmetrical between D. cerastii and N. tenuis, favouring the first. Cannibalism was not significantly different among these mirid species. Our results show that D. cerastii has a greater capacity to feed on intraguild prey than N. tenuis. Therefore, IGP on small nymphs does not explain the abundance shift between D. cerastii and N. tenuis
- Genomic signatures of introgression between commercial and native bumblebees, Bombus terrestris, in Western Iberian Peninsula - implications for conservation and trade regulationPublication . Seabra, Sofia G.; Silva, Sara E.; Nunes, Vera L.; Sousa, Vitor C.; Martins, Joana; Marabuto, Eduardo; Rodrigues, Ana S.B.; Pina-Martins, Francisco; Laurentino, Telma G.; Rebelo, Maria Teresa; Figueiredo, Elisabete; Paulo, Octávio S.Human‐mediated introductions of species may have profound impacts on native ecosystems. One potential impact with largely unforeseen consequences is the potential admixture of introduced with autochthonous species through hybridization. Throughout the world, bumblebees have been deliberately introduced for crop pollination with known negative impacts on native pollinators. Given the likely allochthonous origin of commercial bumblebees used in Portugal (subspecies Bombus terrestris terrestris and B. t. dalmatinus), our aim was to assess their putative introgression with the native Iberian subspecies B. terrestris lusitanicus. We analysed one mitochondrial gene, cytochrome c oxidase subunit I (COX1) and genomic data involving thousands of genome‐wide restriction‐site‐associated DNA markers (RAD‐seq). In the mitochondrial COX1 analyses, we detected one relatively common haplotype in commercial bumblebees, also present in wild samples collected nearby the greenhouses where the commercial hives are used. In the RAD‐seq analysis, we found a clear genetic differentiation between native and commercial lineages. Furthermore, we detected candidate hybrids in the wild, as well as putatively escaped commercial bumblebees, some of which being potentially fertile males. Although we cannot assess directly the fitness effects of introgressed alleles, there is a risk of maladaptive allele introgression to the local bumblebee subspecies, which can negatively impact autochthon populations. One immediate recommendation to farmers is for the proper disposal of hive boxes, after their use in greenhouses, so as to minimize the risk of escapees contaminating native populations. On the other hand, the feasibility of using local subspecies B. t. lusitanicus, preferably with local production, should be evaluated
- Population genomics of Bombus terrestris reveals high but unstructured genetic diversity in a potential glacial refugiumPublication . Silva, Sara E.; Seabra, Sofia G.; Carvalheiro, Luísa G.; Nunes, Vera L.; Marabuto, Eduardo; Mendes, Raquel; Rodrigues, Ana S.B.; Pina-Martins, Francisco; Yurtsever, Selçuc; Laurentino, Telma G.; Figueiredo, Elisabete; Rebelo, Maria T.; Paulo, Octávio S.Ongoing climate change is expected to cause temperature rise and reduction of precipitation levels in the Mediterranean region, which might cause changes in many species’ distribution. These effects negatively impact species’ gene pools, decreasing genetic variability and adaptive potential. Here we use mitochondrial DNA and RADseq to analyse population genetic structure and genetic diversity of the bumblebee species Bombus terrestris (subspecies B. terrestris lusitanicus), in the Iberian Peninsula. While this subspecies shows a panmictic pattern of population structure across Iberia and beyond, we found differentiation between subspecies lusitanicus and subspecies africanus, likely caused by the existence of barriers to gene flow between Iberia and North Africa. Furthermore, results revealed that the Iberian Peninsula harbours a large fraction of B. terrestris intraspecific genetic variation, with the highest number of mitochondrial haplotypes found when compared to any other region in Europe studied so far, suggesting a potential glacial refugium role for the Iberian Peninsula. Our findings strengthen the idea that Iberia is a very important source of diversity for the global genetic pool of this species, as rare alleles may play a role in population resilience against human or climate-mediated changes
- Diversity of Iberian nucleopolyhedrovirus wild-type isolates infecting Helicoverpa armigera (Lepidoptera: Noctuidae)Publication . Figueiredo, Elisabete; Muñoz, Delia; Murillo, Rosa; Mexia, António; Caballero, PrimitivoLarvae of the tomato fruitworm, Helicoverpa armigera, were surveyed for nucleopolyhedrovirus (NPV) infection (referred to as HearNPV) in three different locations from the Iberian Peninsula: Olivenza and Toledo in Spain and the Oeste region in Portugal. Twenty HearNPV isolates were obtained from single field-collected larval cadavers. Restriction endonuclease (REN) profiles of the collected isolates with BglII and PstI allowed identification of six different H. armigera single-embedded NPV strains in Spain (referred to as HearSP3, HearSP4, HearSP5, HearSP6, HearSP7, and HearSP8) and two in Portugal (referred to as HearPT1 and HearPT2). No strains were shared by isolates from different geographical regions except HearSP5, which was found in isolates from Olivenza and Toledo. Cluster analysis based on the restriction fragment length polymorphisms of these strains in relation to two previously identified strains from Badajoz (HearSP1) and Cordoba (HearSP2) in Spain, showed no correlation among the strains and their geographical origin. The biological activity of HearSP2, HearSP4, HearSP7, HearSP8, HearPT1, and HearPT2 was compared in terms of pathogenicity (50% lethal concentration, LC50) and virulence (mean time to death). HearPT2 and HearSP7 were significantly more pathogenic than HearSP2, with LC50 values 2.8 and 2.6-fold higher than the latter, respectively, on H. armigera second instars. HearSP4 and HearPT2 killed larvae significantly faster than HearSP8, whereas HearSP2, HearSP7, and HearPT1 showed intermediate mean time to death values
- Transition toward Agroecology among Family Farmers: Crop Protection PracticesPublication . Costa, C.A.; Aguiar, C.; Parente, C.; Neto, J.; Valério, E.; Godinho, M.C.; Figueiredo, E.