Two strains of Spodoptera frugiperda (J.E. Smith) were first described in the United States; in Brazil, in the states of Rio Grande do Sul, Mato Grosso, and western Paraná they have also been reported. This study was aimed at identifying these strains in Norte Pioneiro and Campos Gerais, in the states of Paraná and southwestern São Paulo. Larvae of S. frugiperda were collected in the cities of Ponta Grossa, Tibagi, Arapoti, and Wenceslau Braz in Paraná, and in the city of Itaberá, in São Paulo. PCR-RFLP genotyping of the COI gene was carried out using sixty-six specimens. Based on their electrophoretic pattern, 51 individuals were identified as corn strain, five as rice strain, and 10 as hybrids (Rice in MspI and Maize in SacI). Our findings indicate that both S. frugiperda strains are present the study areas.

Aedes aegypti L. (Diptera: Culicidae) is a vector of arboviruses associated with dengue, chikungunya, zika and yellow fever. Based on empirical knowledge, plants belonging to genus Crotalaria (Fabaceae) attract dragonflies, which are the main natural predator to A. aegypti and help controlling populations of this mosquito. The aim of the present study is to investigate (i) whether Crotalaria is a food source for A. aegypti and (ii) whether Crotalaria attracts predators to this mosquito, mainly dragonflies. The study was carried out from January to March 2018 in two Crotalaria spectabilis Roth (Fabaceae) cultivation fields, which covered 100 m2 (each) in Missal County, Paraná State, Brazil. Samples of all arthropods foraging on C. spectabilis were collected. Observations in situ were carried out to investigate whether A. aegypti individuals visit C. spectabilis flowers. In total, 14,967 arthropods were recorded foraging on C. spectabilis (288 in cultivation field 1 and 14,679 in cultivation field 2). Dragonflies and damselflies were recorded foraging on C. spectabilis crops, but no A. aegypti individual was recorded in active collections and observations in situ. These results indicate that C. spectabilis works as food source and/or place used by several arthropods to find preys. The incidence of dragonflies and damselflies flying in C. spectabilis monocultures indicates that these plants attract dragonflies, as well as that Crotalaria can help indirectly controlling A. aegypti populations.

Elio Corseuil (20/07/1930-26/07/2020)

Bean (Phaseolus vulgaris L.) cultivation has great agricultural and food importance, but this crop production is generally affected by severe infestations of Cerotoma arcuata (Olivier) (Coleoptera: Chrysomelidae) in the northern region of Brazil. An alternative for leaf beetle control is the use of physiological insecticides acting in the initial phase of plant growth, through pre-sowing seed treatment. In this sense, this study aimed to evaluate the effects of systemic insecticides, based on thiamethoxam, imidacloprid and fipronil, on the germination performance of bean seeds, and to verify the efficacy of these insecticides on the control of C. arcuata. The research was carried out in two stages. Initially, under laboratory conditions, the influence of the insecticides on the germinating power of seeds was evaluated through the following parameters: germination, emergence, electrical conductivity and dry mass of the aerial part. In the field, the efficacy of the insecticides on the plant stand, number of insects per plant and level of foliar damage at 21 and 28 days of planting were evaluated. The insecticides investigated did not affect the germinating power of seeds when compared to the control. Regarding field results, there was a lower incidence of C. arcuata and less leaf damage to plants from seeds treated with systemic insecticides, showing greater crop protection in the period studied.

Fire is a frequent agent of disturbance in tropical savannas (e.g., Brazilian Cerrado), but relatively few studies have analyzed how the arthropod community responds to fire disturbance. Following the incursion of an accidental fire into a Cerrado fragment in Central Brazil, we investigated whether the arthropod community is structured by abiotic (climate or fire) or biotic (succession) factors. Our study commenced one week after fire and during the six months afterward. We found 22 arthropod orders, of which Diptera, Hymenoptera, Hemiptera, Blattaria and Coleoptera were the most representative. More than 40% of the arthropod abundance was recorded 40 days after the fire event. The overall arthropod abundance and richness fluctuated in the six months following the fire and does not seem to be related to climatic variables. Temporal beta diversity was explained by a reduction in richness differences along the intervals of time, but the community recovery needs to be treated with caution. The increase in replacement in the last intervals in relation to the fire event indicates that biotic interactions may occur with the arrival of late colonizers and suggest that arthropod communities need a long time to be restructured. These results indicate that the processes of restructuring of the arthropod communities after human-induced fire events are temporally complex, involving loss, gain and taxon replacement, but long-term studies are still needed to understand the dynamics of communities.

Abstract. The genus Salvinia is composed of fast-growing floating ferns, capable of surviving in different environmental conditions. Some authors suggest that the relationships between this genus and macroinvertebrates may serve as water quality indicators. The present study aimed to determine the influence of seasonality and water quality on macroinvertebrate diversity associated with the Salvinia biloba Raddi. Water and fern were collected in rainy and dry seasons and was conducted a microbiological analysis of the water, as well as, the area of fern cover on the water, richness, and density of macroinvertebrates. Microbiological analysis of the water detected > 5,700 CFU/mL (rainy season) and 175 CFU/mL (dry season) of heterotrophic bacteria and was positive for total thermotolerant coliforms. The S. biloba cover on the water surface was 100% in the rainy and 30% in the dry season. In the rainy season, 142 macroinvertebrates were identified, divided into 12 morphospecies, with a density of 434 individuals/m3. In the dry season, there were 419 individuals in 14 morphospecies, with a density of 2,076 individuals/m3 exhibited. The highest species density recorded in the rainy season was for Chironomidae sp.1 (Diptera) (57.71%) and Odonata Zygoptera sp.1 (17.44%), and in the dry season, Chironomidae sp.2 (73.98%) followed by Gerromorpha sp.1 (Hemiptera), with 9.54%. The Sørensen similarity index between the two seasons was 53.84%. The higher density of Gerromorpha sp.1 in the dry season may indicate an increase in environmental integrity.

The present study aimed to evaluate the insecticidal activity of hydroalcoholic plant extracts on Aphis craccivora Koch nymphs in cowpea. The experiments were carried out under greenhouse conditions in a randomized block design with five repetitions. Hydrated ethanol was used as a solvent in the botanical extract preparation. Cowpea plants were infested with five female adult aphids, eleven days after planting. After 48 hours, the adults were removed from the plants, leaving the recently bred nymphs. The evaluation of the nymphs’ survival was carried out forty-eight 48 hours after the application of the plant extracts. The botanical extracts with more than 50% efficiency were: Allium tuberosum leaf, Caesalpinia ferrea leaf, Piper aduncum leaf, Carica papaya seed, Dieffenbachia picta leaf, Cucurbita moschata seed and the control treatment, Annona squamosa seed. The botanical extracts with less than 50% efficiency were: Allium sativum bulb, Anacardium occidentale leaf, Borreria verticillata leaf plus flower, Coffea arabica leaf and seed, Delonix regia leaf and flower, Euphorbia tirucalli leaf, Leucaena leucocephala leaf, Mimosa caesalpiniaefolia leaf, Nerium oleander leaf, Syzygium cumini leaf, endocarp and pericarp, Syzygium malaccense leaf, Zingiber officinale rizome and Ziziphus joazeiro leaf. The highest efficiency levels were obtained by D. picta and C. moschata, rendering these extracts suitable for field trials to further evaluate their efficieny against the cowpea black aphid.

Pinnaspis strachani (Cooley) (Hemiptera: Diaspididae), a highly polyphagous scale insect and a known pest of various crops, is reported for the first time infesting neem (Azadirachta indica A. Juss., Meliaceae) in Brazil. Infestations of this diaspidid were observed on the trunks, branches, and leaves of neem trees in Barreiras, Bahia, Brazil.

In the state of Acre, Brazil, family-based agriculture is predominant and although it has less economic impact in relation to large-scale plantations, it is also subject to biological imbalances, such as the attack of pests, generating economic losses for producers. Phytosanitary knowledge in the state is still incipient and becomes an obstacle to production, often resulting in mistaken management decisions. In this context, this work aimed to present a history of research carried out in the field of Agricultural Entomology, especially in the areas of integrated management and biological control of pests of the most relevant crops grown in the Acre state. In this review, 55 scientific papers related to Agricultural Entomology were presented, 23 on new insect records and/or new insect associations with host plants, 16 on insect control using plant extracts from the Amazon region, 13 on integrated pest management and three on bioecology and population dynamics of pests in the state of Acre. Through this review, it is observed that research in the area  of Agricultural Entomology in the state of Acre is characterized by basic research (surveys, registration of new species, bioecological and dynamic population studies). However, there has been a notable advance in scientific studies aimed at integrated pest management in the state in the past ten years. Still, there is a need to concentrate efforts on research aimed at prospecting and using Amazonian biodiversity (fauna and flora), which subsidize applied programs for integrated pest management of the main crops grown in the Acre state.