Fall armyworm (FAW) (Spodoptera frugiperda) is a polyphagous insect responsible for damage to several crops. Synthetic chemical insecticides and genetically modified plants are the most commonly used methods for FAW control. However, the selection of resistant populations has been reported in several studies, justifying the search for new molecules to be used in the control of S. frugiperda. The aim of the present study was to evaluate the toxicity of lemongrass (Cymbopogon flexuosus) essential oil (LEO) and its major component (citral) in relation to FAW. Additionally, the anticholinesterase activity of LEO and citral was evaluated using acetylcholinesterase (AChE) from Electrophorus electricus. The LEO was toxic to FAW when added to an artificial diet (LC50 = 1.35 mg mL-1) at the highest concentrations tested, and the median lethal time (LT50) was 18.85 h. Major components of LEO were identified by gas chromatography-mass spectrometry, and citral, the most abundant component, was used in FAW bioassays. The insecticidal activity of citral was statistically similar to that of LEO, demonstrating that citral was responsible for the insecticidal activity of LEO. Inhibition of AChE was measured, and the mean inhibitory concentration (IC50) values for LEO and citral were 650- and 405-fold higher, respectively, than that verified for the positive control (methomyl insecticide), suggesting selectivity for non-target organisms. Based on these results, citral and C. flexuosus have the potential to be applied in the development of new products for the control of S. frugiperda.

Atualmente, a diversificação de frutíferas é uma forte tendência para ampliação de oportunidades para o fruticultor. O cultivo da pitaia se tornou importante, tanto para a economia quanto para a saúde, devido ao exotismo de sua aparência, por suas características organolépticas e suas propriedades nutracêuticas. No entanto, informações sobre o cultivo desta frutífera são escassas, necessitando de pesquisas para facilitar seu manejo. Neste sentido, o presente trabalho teve como objetivo avaliar a influência do manejo do desponte nas características vegetativas e reprodutivas em diferentes tamanhos de cladódios de pitaia vermelha de polpa branca. Para execução do experimento foi utilizado o delineamento experimental inteiramente casualizado, em esquema fatorial 5 x 3, correspondente a cinco comprimento de cladódios (menores que20 cm, entre 20-40 cm, 41-60 cm, 61-80 cme maiores que80 cm) e o segundo se refere a três tipos de desponte (sem desponte do cladódio, com desponte em setembro e desponte em outubro). Utilizaram-se 6 repetições e 1 cladódio por parcela. Foram analisadas as seguintes características: comprimento das brotações, números de brotações, número total de flores, quantidade de flores abortadas e frutos, porcentagem de pegamento das flores e massa fresca dos frutos. O desponte de cladódios não influenciou na maioria das características avaliadas. No entanto, para a melhor floração e produção de frutos, recomenda-se priorizar o desponte nos cladódios superiores a60 cmde comprimento.Palavras-chave: Cactácea. Frutificação. Hylocereus undatus. Poda.AbstractCurrently the diversification of fruit is a strong tendency to increase opportunities for the fruit grower. Pitaya cultivation has become important for both economy and health, due to the exotic nature of its appearance, its organoleptic characteristics and its nutraceutical properties. However, information on the cultivation of this fruit is scarce, requiring research to facilitate its management. Therefore, the present work had as objective to evaluate the influence of the topping management in the vegetative and reproductive characteristics in different sizes of cladodes of  white fleshed red pitaya. In order to carry out the experiment, the completely randomized experimental design in factorial scheme 5 x 3 was utilized, corresponding to five cladode lengths (shorter than 20 cm, between 20-40 cm, 41-60 cm, 61-80 cm and longer than 80 cm) and the second is regarding  the three kinds of topping (no topping of the cladode, with topping in September and topping in October). Six replications and one cladode per plot were used . The following characteristics were investigated: length of the shoots, number of shoots, total number of flowers, amount of aborted flowers and fruits, percentage of flower set and fresh mass of fruits. The topping of cladodes did not influence the evaluated characteristics. For the best flowering and fruit production, it is advisable to prioritize  the cladodes over 60 cm long.Keywords: Cactaceae. Fructification. Hylocereus undatus. Pruning.

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The objective of the present study was to verify the technical feasibility of using banana pseudostem fibers in the manufacture of MDP in intermediate panel layers, in different associations with wood from eucalyptus and banana pseudostem. The physical properties of water absorption and thickness swelling for immersion in water for both 2 and 24 hours were evaluated. Three panels were produced according to American Standard ASTM D 1037. 12% urea-formaldehyde adhesive were used for the production of panels. The pressing cycle was 4 MPa, with a temperature of 160°C for a period of 8 minutes. The panels were produced with a density of 0.70g/cm3 and had the following composition: 20/60/20 face/core, in which the face consisted of eucalyptus and varying proportions of pseudostem in the core (10%, 20% and 30%) and in eucalyptus. It is observed that the panels with 20% particles in the core showed the best results, compared to other panels evaluated.

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