Corn (Zea mays) is one of the world's main agricultural crops, and Spodoptera frugiperda (J. E. Smith) is its most important pest. In order to find natural controlling alternatives, this study aimed to determine the effect of plant oils on the feeding preference of first-and second-instar caterpillars. The experimental design was completely randomized in a 6 x 5 factorial combination (turmeric, clove, palmarosa, tea tree, common juniper, and neem oils) at five concentrations (0, 25, 50, 100, and 200 µL mL-1), plus a control consisting of acetone 100.0%, with five replicates per treatment. Twenty-five-day-old corn leaf sections received the corresponding treatments in addition to the control and were deposited along orthogonal axes in an arena arranged in Petri dishes. Ten 1 st instar caterpillars were released at the center of the plates, and results were obtained after 8h and 24h from the release, based on the number of caterpillars found on each treatment. For 1 st instar caterpillars, the best results were observed for clove and palmarosa, which negatively influenced caterpillar feeding activity in both evaluation periods, followed by turmeric oil, which showed the same effectiveness in the last period only. For second-instar caterpillars, the best effects were observed for neem, turmeric, palmarosa, and clove oil in the first evaluation period. Furthermore, the effectiveness of the first three oils was maintained in the second evaluation period. These results emphasize the potential capability of plant oils when used in management programs against this pest, in which the oils of turmeric, clove and palmarosa showing the best controlling potential of this pest from the lowest concentration corresponding to 25 µL mL-1 .

O descarte incorreto dos recipientes plásticos usados na produção de mudas causa impactos ao ambiente. O maracujazeiro amarelo é produzido em grande escala, tendo importância fármaco-terapêutico, além de ser uma frutífera de produção rápida, sendo para isso imprescindível a obtenção de mudas de qualidade. O objetivo deste trabalho foi avaliar recipientes e substratos na formação de mudas de maracujazeiro. O experimento foi conduzido num delineamento inteiramente casualizado, em esquema fatorial 2 x 4, sendo 2 recipientes e 4 substratos. Como recipientes foram utilizados bucha vegetal e sacos plásticos. Em cada recipiente foram testados os seguintes substratos: 30% de esterco bovino + 70% de vermiculita; 30% de Bioplant + 70% vermiculita; 30% de esterco bovino + 70% de areia; 30% de Bioplant + 70% areia. Foram avaliadas variáveis referentes a altura, diâmetro do colo, fitomassas e relações biométricas. As mudas mais vigorosas de maracujazeiro foram obtidas com o recipiente de polietileno. Para os substratos, o melhor resultado foi observado utilizando-se a mistura de esterco e vermiculita.

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Tetrastichus howardi (Olliff, 1893) (Hymenoptera: Eulophidae) is an adult parasitoid of lepidopteran pests, and the age of the host has a strong influence on its reproduction. This study aimed to evaluate the biological characteristics of T. howardi reared on different aged pupae of Chrysodeixis includens (Walker, [1858]) (Lepidoptera: Noctuidae). For that, pupae with 24, 48, 72, 96, 120, 144 or 168 h of age were exposed to parasitism. The experimental design was completely randomized, with seven treatments (pupal age) and ten replications, with each replication consisting of five pupae individualized with one female parasitoid at the respective ages. Tetrastichus howardi parasitized and emerged in pupae of all the evaluated ages. The duration of the cycle (egg-adult) in days, number of parasitoids that emerged per pupa (progeny), progeny per female, sex ratio of the parasitoid and longevity of adults were similar. This is the first record of T. howardi reproducing in C. includens pupae under laboratory conditions. The highest parasitism and development of T. howardi was obtained in 24-to 96-hour-old pupae of C. includens, indicating that this age range is more favorable to rear this parasitoid under laboratory conditions.