The South American palm weevil (SAPW), Rhynchophorus palmarum Linnaeus (Coleoptera: Curculionidae) is the main pest of Elaeis guineensis and damages palm trees with bud rot disease in the Americas. The effects of six neurotoxic insecticides (abamectin, carbaryl, deltamethrin, fipronil, imidacloprid and spinosad) were evaluated against SAPW for toxicity, survival, reproduction, and mortality. Abamectin (LC50 = 0.33 mg mL−1), Carbaryl (LC50 = 0.24 mg mL−1), deltamethrin (LC50 = 0.17 mg mL−1), and fipronil (LC50 = 0.42 mg mL−1) were the most toxic to SAPW. Adult survival was 95% without exposure to insecticides, decreasing to 78–65% in insects treated with the LC25 and 49–35% in insects exposed to LC50. Sublethal doses of carbaryl, fipronil and imidacloprid showed significant effect on the reproduction of this insect. Mortality of SAPW populations caused by insecticides had similar effects in the laboratory and field conditions. The results suggest that carbaryl, deltamethrin, fipronil, and imidacloprid caused significantly higher mortality as compared to the control in SAPW and may be used to control its populations in oil palm trees where bud rot appears as the key disease for SAPW attraction and infestation.

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Introduction: Soybean Looper Crysodeixis includes (Walker) (Lepidoptera: Noctuidae) is a major pest of soybean and cotton in Brazil. Methods: A total of 1,647 caterpillars were collected in soybean fields, in two different locations during a two year period of cropping system. Larvae were reared individually on artificial diet and observed daily. Each larva with baculovirus symptom was macerated with sterilized water, filtered and provided to healthy larvae from the artificial rearing. Those larvae that died with symptoms were collected together, for each isolate. After purification baculovirus isolate 15 was used in the 10 e 10 concentrations with 15,16,17 and 18 days old larvae, room temperatures of 25°C and 28°C. 16 larvae per treatment were fed for 24h in soy leaves infected with purified baculovirus.

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A 6-year field monitoring study was designed to compare the presence of fall armyworm Spodoptera frugiperda (J. E. Smith), leaf injury, its parasitoids, 100 seed weight, and seed yield of Bt maize hybrids approved for commercialization in the Brazilian market. Field trials were planted in two municipalities, divided into two periods, from 2011 to 2014 (period I), and due to the approval of different Bt hybrids, from 2015 to 2016 (period II). Treatments were Bt, non-Bt maize and all non-Bt maize sprayed with insecticide methomyl. Six Bt-maize hybrids were planted, expressing the following proteins: Cry1Ab, Cry1F, Cry1A.105 (Cry1Ab +Cry1Ac +Cry1F), Cry2Ab2a and Vip3. In 2015 and 2016 Bt Powercore was planted due to its commercial approval. The number of S. frugiperda larvae for most Bt hybrids was lower than on non-Bt hybrids, except for Fórmula TL and Herculex in period II, in both municipalities. In period I, Bt hybrids VT, VT 2 and Viptera showed almost no injury on their leaves, despite the high number of fall armyworm larvae found in plants. Different parasitoids emerged from larvae from Bt and non Bt hybrids: Archytas sp., Campoletis sp., Chelonus sp., Eiphosoma sp. and Ophion luteus. The average 100 seed weight was higher in municipality from Sete Lagoas for all Bt hybrids, non-Bt hybrids and non-Bt hybrids sprayed with methomyl, when compared to Nova Porteirinha during period I. Fórmula TL, non-Bt Fórmula TL sprayed with methomyl, and non-Bt Fórmula TL showed the lowest seed yield in both municipalities and periods.