ABSTRACT The association of adjuvants with phytosanitary products has been tested for several years but is commonly recommended without considering technical and scientific criteria. This study aimed to evaluate the influence of the association of insecticides with different adjuvants on surface tension, contact angle, coverage, hydrogen ionic potential (pH), and the formation of deposits exposed to rain. The insecticides thiamethoxam, imidacloprid, and lambda-cyhalothrin were tested at doses of 75 g ha−1, 150 g ha−1, and 150 g ha−1, respectively, with a spray volume of 200 L ha−1. Break-Thru 240®, Break-Thru 233®, Break-Thru Union®, Oleo FC Agraröl®, and Naturo'il® were added to each of these spray solutions. The results showed that the addition of adjuvants reduced the surface tension and contact angle, and consequently, increased droplet coverage. No deposit pattern was found in the thiamethoxam, imidacloprid, and lambda-cyhalothrin insecticides associated with the adjuvants and a higher amount of residue was observed on wheat leaves than on maize leaves. The use of adjuvants can be an alternative to improve the efficiency of insecticides, allowing the product to achieve its full control potential.

Abstract In this work the bioherbicide production from Phoma sp. by solid-state fermentation was optimized. Agroindustrial residues such as bagasse, soybean bran and corn steep liquor were used as substrate. The bioherbicide was extracted from the fermented solid and the supernatant was applied for the control of the target plant. The evaluated responses in the bioassay were plant height, root length, fresh and dry weight, number of flowers and phytotoxicity. The results in the bioassays demonstrated that the bioherbicide presented activity towards the target plant and the intensity of the effect was influenced by the formulation of the fermentation medium. The optimized condition for bioherbicide production was (wt%): moisture content 70.0, soybean bran content 30.0 and corn steep liquor (CSL) 20.0, it being possible to obtain an injury phytotoxicity level of 40. The bioherbicide showed a mode of action based on the inhibition of carotenoid biosynthesis.

White grubs (Coleoptera, Melolonthidae) in the "Planalto Region", Rio Grande do Sul state, Brazil: Key for identification, species richness and distribution. The objective of this study was to survey the occurrence and geographic distribution of white grub species (Coleoptera, Melolonthidae) in cultivated and non-cultivated fields of the "Planalto Region", Rio Grande do Sul state, Brazil and develop a key at genus-level. Twenty-eight species from 15 genera and three subfamilies were recorded: Dynastinae, Melolonthinae and Rutelinae. The species or genera recorded for the first time in the state are: Cyclocephala metrica, C. tucumana, Isonychus albicinctus, Liogenys bidenticeps, L. fusca, L. obesa and L. sinuaticeps, Paranomala violacea, as well as unidentified species of Amononyx, Dicrania, Leucothyreus, Macrodactylus, Plectris and Rhizogeniates. Among the species recorded, 23 were associated with winter crops. Only Cyclocephala metrica, Dyscinetus rugifrons, two species of Leucothyreus and one species of the tribe Sericini were not present in cultivated crop fields. Cyclocephala flavipennis and Diloboderus abderus occurred in most of the municipalities sampled, often associated with Plectris sp., C. modesta and C. putrida. The highest richness of melolonthids was concentrated in the northeast of the Planalto region.

Normalmente, a aplicação de inseticidas para o controle de Anticarsia gemmatalis na cultura da soja é realizada com bicos hidráulicos. Dentre outras possibilidades se destacam a assistência de ar junto à barra de pulverização e a aplicação de baixo volume oleoso por atomizadores rotativos de discos. Em um experimento realizado na cultura da soja, na safra 2009/10, avaliou-se a eficiência de controle de A. gemmatalis utilizando-se sistemas de aplicação e inseticidas. O delineamento utilizado foi bifatorial com o fator A constituído por sistemas de aplicação, sendo: A1 - pulverização com atomizadores rotativos de discos; A2 - pulverização com bicos hidráulicos; A3 - pulverização com assistência de ar e o fator D, constituído por inseticidas, sendo: D1 - Cipermetrina e D2 - Lufenurom + profenofós. Não houve interação do inseticida com o sistema de aplicação; além disso, a mistura de inseticidas Lufenurom + Profenofós apresentou efeito residual superior a Cipermetrina. O sistema de aplicação baixo volume oleoso com atomizadores rotativos de discos e o sistema de bicos hidráulicos com assistência de ar junto à barra de pulverização são mais eficientes que a pulverização com bicos hidráulicos no controle de Anticarsia gemmatalis na cultura da soja.

The application of insecticides to control Anticarsia gemmatalis in soybean is through hydraulic nozzles. Among the innovations stands out the air-assisted boom sprayer and the application of low oil volume by a rotary discs atomizer. In an experiment conducted with soybean during the 2009/2010 growing season, the control efficiency of A. gemmatalis using application systems and insecticides was assessed. The experimental design was a two-factor, with the factor A being the application systems, as follows: A1 - spraying with rotary discs atomizer; A2 - spraying with hydraulic nozzles and A3 - spraying with air-assistance; and factor D was composed of insecticides, as follows: D1 - Cypermethrin and D2 - Lufenuron + Profenofos. There was no interaction between insecticide and application systems and the insecticide Lufenuron + Profenofos presented a superior residual effect than Cypermethrin. The low oil volume spray system with rotary discs atomizer and system hydraulic nozzles with air-assisted boom sprayer are more efficient than hydraulic nozzles to control Anticarsia gemmatalis in soybean.

Primeiro registro de ocorrência de espécies de Liogenys (Coleoptera, Melolonthidae) associadas a culturas de inverno no Rio Grande do Sul (Brasil). As espécies de Liogenys Guerín-Meneville, 1831 são conhecidas no "Cerrado" brasileiro por causar danos em culturas de verão como soja e milho. O trabalho teve por objetivo identificar as larvas de melolontídeos que ocorrem nas culturas de grãos de inverno no Rio Grande do Sul. Larvas e adultos de Liogenys foram coletados nos municípios de Ijuí, Cruz Alta, Manoel Viana, São Luiz Gonzaga e São Francisco de Assis. As espécies foram identificadas como Liogenys bidenticeps Moser, 1919, L. fusca Blanchard, 1851, L. obesa Burmeister, 1855 and L. sinuaticeps Moser, 1918. Trata-se do primeiro registro de ocorrência destas espécies associadas a culturas de grãos de inverno, no Estado de Rio Grande do Sul. São necessários estudos de biologia e comportamento para confirmar sua associação com plantas hospedeiras.

First record of species of Liogenys (Coleoptera, Melolonthidae) associated with winter crops in Rio Grande do Sul (Brazil). Some species of Liogenys Guerín-Meneville, 1831 are known to cause damage to soybean, corn and other summer crops in the Brazilian "Cerrado" region. This work aimed to identify melolontid larvae associated with winter crops in Rio Grande do Sul state. Larvae and adults of Liogenys species were collected from the municipalities of Ijuí, Cruz Alta, Manoel Viana, São Luiz Gonzaga and São Francisco de Assis. The specimens were identified as L. bidenticeps Moser, 1919; L. fusca Blanchard, 1851, L. obesa Burmeister, 1855, and L. sinuaticeps Moser, 1918. This is the first record of these species associated with winter grain crops, for Rio Grande do Sul State. Biological and behavioral studies are necessary to confirm their association with host plants.