The Tibraca limbativentris is a pest that causes rice crop damage and may lead to grain yield reductions of up to 90%. The most commonly used tactic for T. limbativentris control is chemical, which causes adverse effects on the environment. This study was conducted to identify sources of antixenosis and antibiosis resistance to T. limbativentris mediated by the hardness and diameter of the stem of the rice plant. Antibiosis and antixenosis tests were carried out with 22 rice genotypes of Brazilian and Asian origin. The Canela de Ferro, BRS Esmeralda, and Desconhecido Branco genotypes had the lowest proportions of stems showing symptoms of the damage caused by T. limbativentris. Canela de Ferro, Primavera, and IR 22 genotypes had the lowest nymphs survivorship and the genotypes Marabá Branco, Marabá, Skirivimankoti, Pepita, BR IRGA 409, Curinga, IR 40, Bonança, Desconhecido Branco, Bico Ganga, Primavera, and BRS Esmeralda were the least attractive to the insects. The genotypes BRS Esmeralda, Primavera, Desconhecido Branco, and Canela de Ferro were resistant to the rice stalk stink bug by antibiosis and/or antixenosis. These genotypes can be used directly by rice farmers for T. limbativentris management. Molecular biology studies should be conducted to identify and characterize resistance genes in these genotypes so that they can be used in breeding programs.

Chickpea is a legume with nutrient-rich grains important for human feeding. Tobacco budworm, Chloridea virescens (Lepidoptera: Noctuidae), is one of the most major pests of chickpea (Cicer arietinum) in Brazil. This pest damages leaves, flowers, pods, and grains. Plant resistance to insects is an important tactic of pest management, which usually facilitates and reduce costs of implementing an Integrated Pest Management for farmers. Thus, this study aimed to evaluate the resistance in chickpea cultivars to C. virescens. Six chickpea cultivars were evaluated for antixenosis, initial antibiotic parameters, and behavior under field conditions. The cultivars BRS Kalifa and BRS Cícero were less attractive in a free-choice test, while Jamu 96 and BRS Kalifa were less attractive in a no-choice test. BRS Kalifa and BRS Toro leaves had a higher trichome density. Jamu 96 and BRS Toro had higher contents of oxalic and malic acids. C. virescens larvae in BRS Cícero, BRS Toro, and BRS Kalifa showed the lowest weights. Jamu 96 pods were the least damaged, and BRS Aleppo and Jamu 96 had the highest yields. The chickpea cultivars Jamu 96 and BRS Aleppo, which had resistance levels and mechanisms, can be used in integrated pest management programs to control C. virescens.

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This study evaluates the effects of combinations of pyrethroids and neonicotinoids on the control of stink bugs at different stages of soybean crop development. The experiment was set up in a factorial randomized block design (4×6: 4 treatments and 6 stages) with 4 repetitions. The following treatments were tested during the V6/V7, R2, R4, R5.1, R5.5 and R 6 phenological stages: 1 – control (no application), 2 – thiamethoxam + λ-cyhalothrin, 3 – acetamiprid + α-cypermethrin, and 4 – dinotefuran + α-cypermethrin. Infestation, number of damaged seeds, number of pods, number of pods per plant, and yield (kg/ha) were evaluated. Stink bug infestations were smaller when applications commenced during the vegetative stages (V6-V8). Pod numbers and yields were highest in the dinotefuran + α-cypermethrin treatment with applications from V6/V8 to R4. The active ingredients dinotefuran + α-cypermethrin reduced stink bug populations and increased yields and could therefore be considered in integrated pest management (IPM) programs for soybean crops.