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Fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is the main pest of maize in Brazil, attacking plants from emergence to reproductive stages. Here, we conducted studies to evaluate the efficacy of two seed treatments (chlorantraniliprole alone and imidacloprid combined with thiodicarb) on Bt and non-Bt maize in laboratory bioassays with distinct FAW strains that are susceptible, selected for resistance to Bt-maize single (Cry1F) or pyramided (Cry1A.105 + Cry2Ab2) events and F1 hybrids of the selected and susceptible strains (heterozygotes), and in the field against a natural infestation. In the laboratory, leaf-discs from seed treated Bt-maize plants at 7 d after emergence (DAE) increased the mortality of FAW resistant, heterozygote, and susceptible strains up to 24.8%, when compared with the respective maize grown without a seed treatment. In the field against natural infestations of FAW, Bt maize with a seed treatment had ~30% less FAW damage than non-Bt maize with the same seed treatment at 7 and 14 DAE. No differences in FAW damage was observed between Bt and non-Bt maize grown with and without a seed treatment at 21 DAE. Maize seeds treated with chlorantraniliprole alone or imidacloprid and thiodicarb combined presented limited protection against early infestations of FAW strains under laboratory and field studies.

In Brazil, Asian rust is the main disease that affects the soybean crop, which is responsible for the great inventiveness of financial resources with fungicides to control this pathogen. The objective of this work was to evaluate the grain yield and economic viability of the different combinations of fungicides used in the soybean crop. The experiment was conducted in the 2014/2015 agricultural year in the experimental field located in the municipality of Campo Novo-RS, Brazil. The treatments used correspond to 15 combinations of fungicides, and these were applied at different times during the soybean cycle. The characters measured weremass of 1000 seeds, grain yield, gross income, fungicide cost, total cost, net income, income gain and profitability. The grain yield of soybeans was reduced by 35% due to the absence of fungicide applications. Combinations of fungicides that provide the highest yields and profitability for soybean are based on the use of different active principles such asstrobilurins and carboxamides.

Corn kernels or seeds that remain after harvest can germinate and become a troublesome volunteer plant where bean crops are grown. The objective of this study was to evaluate the effect of time of emergence of volunteer corn on growth parameters, photosynthetic pigments and chlorophyll fluorescence in bean plants, competition for soil and light and light resources. The study was conducted in completely randomised experimental design, in 2×2×2+2 factorial scheme with four replications, involving two bean cultivars in competition with volunteer corn, emerging seven days before and simultaneously with beans, besides the partitioning of the competition by soil and light, just light and two controls without competition. We measured the levels of chlorophyll a, b, total and carotenoids, parameters related to chlorophyll fluorescence and bean growth variables. Volunteer corn was more competitive when it emerged seven days before the beans. When competition was established by light resource, there was a reduction in photosynthetic pigments and morphological variables of the bean plants. When competition by soil and light resources occurred, there was a reduction not only in photosynthetic pigments and morphological characteristics, but also in the chlorophyll fluorescence variables. There were significant correlations between the growth variables of the bean plants and chlorophyll fluorescence, which makes it an important analytical tool for quantifying the stress caused by weeds.

Background Field-evolved resistance of fall armyworm (FAW), Spodoptera frugiperda (Smith), has been reported to Bt maize technologies in Brazil. The control failures of FAW by Bt maize increased the use of insecticides for their control. However, no information is available on the interaction between resistant FAW and their response to insecticides. Here, we evaluated the survival of FAW strains on Bt and non-Bt maize in laboratory and field conditions, and their susceptibility to insecticides. Results In the laboratory, resistant FAW larvae reared on Bt and non-Bt maize showed a similar susceptibility to spinetoram (LC50 = 0.16-0.18 µg a.i. cm-2 ) and chlorfenapyr (LC50 = 0.17-0.20 µg a.i. cm-2 ). However, their susceptibility was lower than that of the susceptible strain reared on non-Bt maize: LC50 = 0.05 (spinetoram) and 0.08 (chlorfenapyr) µg a.i. cm-2 . In contrast, heterozygous strains had similar susceptibility to the susceptible strain. In field trials, no differences in FAW survival were detected between strains when the commercial dose of two insecticides was applied in Bt and non-Bt maize. Conclusion FAW strains surviving on Bt and non-Bt maize, at the same development stage, have similar susceptibility to insecticides. The integrated pest management practices and insect resistance management importance of these results are discussed. © 2019 Society of Chemical Industry.

Soybean looper (SBL), Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae), is an important pest of soybean and cotton in Brazil. The use of insecticides is one of the main control tactics against this pest. To support Integrated Pest Management (IPM) and Insect Resistance Management (IRM) programs, we characterized the susceptibility of Brazilian populations of SBL to insecticides. Field populations were collected from soybean fields during the 2016-2017 and 2017-2018 crop seasons. In the laboratory, late L2/early L3 larvae were exposed to insecticides in diet-overlay or topical bioassays. Field populations of SBL showed high susceptibility to spinetoram (LC50 = 0.074-0.25 μg a.i. per cm2), indoxacarb (LC50 = 0.46-0.94 μg a.i. per cm2), thiodicarb (LC50 = 9.14-36.61 μg a.i. per cm2), chlorantraniliprole (LC50 = 0.15-0.57 μg a.i. per cm2), flubendiamide (LC50 = 0.45-2.01 μg a.i. per cm2), and chlorfenapyr (LC50 = 0.15-0.25 μg a.i. per cm2); the resistance ratios were less than 16-fold. In contrast, SBL populations have reduced susceptibility to lambda-cyhalothrin (LC50 = 3.71-9.54 μg a.i./cm2), methoxyfenozide (LC50 = 0.67-4.23 μg a.i. per cm2), novaluron (LC50 = 27.52-77.63 μg a.i. per cm2), and teflubenzuron (LC50 = 13.41-73.02 μg a.i. per cm2). The resistance ratios relative to a Lab population (susceptible of reference) was up to 38-, 63-, 1,553-, and 5,215-fold, respectively. These high resistance ratios can be associated with resistance evolution. Implications of these findings to IPM and IRM programs are discussed.

BACKGROUND Fall armyworm, Spodoptera frugiperda (J. E. Smith), is a relevant global pest due to severe damage caused on agricultural crops and its capacity to evolve resistance to insecticides. Here, we selected a strain of S. frugiperda resistant to emamectin benzoate under laboratory conditions to understand the inheritance patterns, cross-resistance and synergism involved in the resistance. RESULTS The emamectin benzoate-resistant (Ben-R) strain was isolated by using F2 screen in a field population collected in Lucas do Rio Verde, Mato Grasso state, Brazil. After ten generations of selection pressure with emamectin benzoate, the estimated LC50 of the Ben-R strain was 678.38 μg a.i. mL-1 whereas that of the susceptible (Sus) strain was 0.29 μg a.i.mL-1 , resulting in a resistance ratio (RR) of ~ 2340-fold. The LC50 values of the offspring from reciprocal crosses of Sus and Ben-R strains were 93.37 and 105.32 μg a.i. mL-1 , suggesting that resistance is an autosomal incompletely dominant trait. The high survival of heterozygous and Ben-R strains (>92%) on non-Bt maize sprayed with the field rate of emamectin benzoate confirmed that resistance is functionally dominant. The minimum number of segregations influencing resistance was 3.55, suggesting a polygenic effect. Low cross-resistance was detected between emamectin benzoate and the insecticides methomyl, chlorpyrifos, lambda-cyhalothrin, spinetoram, indoxacarb and chlorantraniliprole (RR

Soybean looper (SBL), Chrysodeixis includens (Walker), is an economically important soybean and cotton pest in Brazil. Here, we selected an SBL strain resistant to teflubenzuron using F2 screening, estimated the resistance allele frequency, characterized the inheritance of resistance, investigated fitness costs, evaluated patterns of cross-resistance, and determined the magnitude of resistance. The teflubenzuron-resistant strain (Teflu-R) was selected from field-collected populations with an estimated allele frequency of 0.1700. Estimated LC50 values were 0.010 and 363.61 μg a.i. cm−2 for the susceptible (Sus) and Teflu-R strains, respectively, representing a 36,361-fold resistance ratio (RR). The LC50 values of reciprocal crosses were 1.02 and 0.59 μg a.i. cm−2, suggesting that resistance is autosomally inherited. The low survival of reciprocal crosses (16 and 20%) on teflubenzuron-sprayed leaves indicates incomplete recessive resistance. The number of segregations influencing resistance was 2.72, suggesting a polygenic effect. The Teflu-R strain showed longer development periods as well as lower survival and population growth than the Sus strain, revealing fitness costs. The Teflu-R strain also showed high cross-resistancesto other chitin inhibitor insecticides, such as novaluron (RR = 6147-fold) and lufenuron (RR = 953-fold), but low cross-resistance to methoxyfenozide, flubendiamide, and indoxacarb (RR

The Chrysodeixis includens nucleopolyhedrovirus (ChinNPV: Baculoviridae: Alphabaculovirus) is a registered insecticide for the management of soybean looper, Chrysodeixis includens (Walker, [1858]) in Brazil. We conducted studies of baseline susceptibility of Brazilian populations of C. includens to the ChinNPV (Chrysogen, AgBiTech, Fort Worth, TX) as valuable knowledge in support of Integrated Pest Management and Insect Resistance Management programs. In bioassays, neonates were infected with different concentrations of ChinNPV using the droplet feeding bioassay method. Larvae were then transferred to artificial diet and mortality was assessed at 7 d. Results confirm that neonates from Brazilian populations of C. includens are susceptible to ChinNPV. Concentrations from 1.0 × 103 to 1.0 × 108 occlusion bodies (OBs) per ml caused mortality from 1.5 to 99%, respectively. The LC50 ranged from 1.4 × 105 to 7.7 × 105 OBs per ml for populations of C. includens (5.5-fold variation). Similar variation was detected for the LC90 which ranged from 1.6 × 107 to 7.7 × 107 OBs per ml (4.8-fold variation). Importantly, the field-collected populations showed equivalent susceptibility to the reference susceptible population. This indicates a low interpopulation variation in susceptibility of Brazilian populations of C. includens to ChinNPV, representing natural geographic variation and not variation caused by previous selection pressure. The candidate diagnostic concentration of 2.9 × 108 OBs per ml was estimated based on the pooled data and caused mortality ranging from 98.6 to 100%. This concentration will be used in proactive resistance monitoring programs. The Chrysogen will be a valuable tool as a new mode of action in C. includens resistance management in Brazil.

The occurrence, distribution, and intensity of damages caused by 'Melanagromyza sojae' on soybean fields in Brazil and Paraguay indicate the need of information regarding the effect of insecticides and mode of applications to its control. The aim of this study was to evaluate insecticide applications at soybean sowing and during the early soybean stages to control 'M. sojae'. Two experiments were carried. In the 1st experiment, 12 insecticides were applied at sowing as a seed treatment (ST) or in the sowing furrow (SF) and combined with presence or absence of foliar spray (FS) of insecticides at 18 and 28 days after soybean emergence (DAE) in a factorial scheme. In the 2nd experiment, 17 insecticides were sprayed foliar at 10 and 22 DAE. Control efficiency of M. sojae was assessed on experiment 1 at 22, 28 and 38 DAE and on experiment 2 at 22 and 38 DAE, by counting the number of larvae, pupae, and damaged plants and length of galleries. The results evidenced the need of a specific management for this pest and recommended application of insecticides such as: Chlorantraniliprole (ST), Imidacloprid + Bifenthrin (ST), Fipronil (ST), Imidacloprid (ST) and Thiamethoxam (SF) at sowing, combined with the foliar spray until 10 DAE of Chlorpyrifos, Thiametoxam + Lambda-Cyhalothrin, Thiodicarb, Bifenthrin and Imidacloprid + Beta-cyfluthrin. The foliar spray should be repeated at least once in an interval shorter than 10 days, to protect soybean plants during the most vulnerable development stages to the attack of 'M. sojae'.

Euschistus heros (Hemiptera: Pentatomidae) is considered a major insect pest in soybean production in Brazil. The indiscriminate application of pesticides to fields leads to reduction in biodiversity, selection of resistant populations, emergence of new pest outbreaks, and damage to non&#...

Rice (Oryza sativa L.) presents a strategic role in social and economic levels. The aim of this study was to elucidate the presence of genetic variability for the genus Oryza, and the possibility of using genotypes with wild characteristics in rice breeding programs. The Oryza genus shows great genetic variability through wild genotypes available in the most varied environments around the world. The negative effects imposed by abiotic stresses such as flood, salinity, low temperatures, water deficiency and high temperatures may be minimized by the efficient identification of a genetic variability source from the Oryza genus. Among the main wild species presented by the Oryza genus, Oryza glumaepatula stands out being an active source of germplasm. The occurrence and preservation of genetic variability of Oryza genus is indispensable to obtain new rice genotypes, to guarantee food security for the human population, as well as to develop genotypes that adapt to climatic changes and natural adversities.

Among the various quality control tests of seeds, the electrical conductivity test has great potential to determine seed quality quickly and reliably. Because of paucity of information in the literature regarding the methodology of the electrical conductivity test for proso millet seeds, this study aimed to evaluate the electrical conductivity test, with periods of imbibition, water volumes and number of seeds, seeking to establish the methodology more suitable for stratification of the lots. The work involves three experiments: characterization of the lots; determining the number of seeds x volumes of water to be used (25, 50, 75 and 100 seeds and 25, 50, 75, and 100 mL of water); and conditioning period (2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 hours). The characterization of lots defined the Lot 1 and Lot 4 as the strongest among the lots evaluated. The electrical conductivity test was efficient to evaluate the physiological potential of lots of proso millet seeds. The stratification of the seed lots was possible using 25 seeds, imbibed in 50 mL of deionized water for a period of 14 hours.

Poultry and pork farming are typical activities of small farms in southern Brazil. This production plays an important social and economic role in many of these areas as it is often the main income source. The swine compost has emerged as an alternative to reduce the volume of swine wastewater, which is transformed into a residue that can be easily transported and applied with less environment prejudice. However, there is no information in literature regarding the use of this compound as a source of nitrogen in grain crops. Therefore, the aim of this study was to evaluate poultry litter and swine compost as organic sources of nitrogen for the millet crop. The experiment was conducted in the years of 2013 and 2014 in southern Brazil, in no-tillage systems in a Hapludox soil. The treatments were: control (without nitrogen); poultry litter (PL), swine compost (SC) and mineral fertilization (NPK). The use of poultry litter resulted in better averages for almost all evaluated variables. Although the swine compost did not express results as good as the crop treated with poultry litter, the crop in which the swine compound was applied presented better results for some plant parameters than the chemical fertilizer treatment, which shows that these two residues can be viable alternatives for nitrogen fertilization in millet cultivations. A criação de aves e suínos são atividades típicas de pequenas propriedades na região sul do Brasil erepresentam um papel importante sob o ponto de vista social e econômico, pois em muitas dessas unidades são as principais geradoras de receita. O composto de suínos tem surgido como alternativa que reduz o volume de dejeto liquido de suínos, e o transforma em um resíduo de fácil transporte e aplicação e menor impactante ao meio ambiente. Porém, não existe na literatura informações quanto a utilização desse composto de suínos como fonte de nitrogênio em culturas produtores de grãos. Por isso, o objetivo deste trabalho foi avaliar a cama de frango e o composto de suínos como fontes orgânicas de nitrogênio na cultura do painço. O trabalho foi conduzido nos anos de 2013 e 2014 na região Sul do Brasil, em sistema plantio direto em um Hapludox soil. Os tratamentos foram os seguintes: Testemunha (sem nitrogênio); Cama de aves (CA), Composto de suínos (CS) e Adubação mineral (NPK). A cama de aves foi a que mais impactou positivamente para quase todas as variáveis analisadas. Já o composto de suínos foi inferior a cama de aves, porém para alguns parâmetros de planta igual ou superior a própria adubação química mostrando que esse dois resíduos podem substituir totalmente a adubação mineral nitrogenada na cultua do painço.

Background Soybean aphid, Aphis glycines, is an invasive insect in North America, considered one of the most important pests of soybean. Their management relies heavily on foliar insecticides, but there is growing effort to expand these tools to include aphid-resistant varieties. We explored if the LC50 and LC25 of lambda-cyhalothrin varied between virulent (resistant to Aphis glycines (Rag) soybeans) and avirulent (susceptible to Rag-genes soybeans) populations of soybean aphid with a leaf-dip bioassay. We also investigated the response to the LC25 of lambda-cyhalothrin on adults (F0) and their progeny (F1) for both avirulent and virulent soybean aphid. Results The LC50 of the virulent aphid population was significantly higher compared with the LC50 of the avirulent population. The LC25 significantly reduced fecundity of the F0 generation of avirulent soybean aphid, but no significant effect was observed for virulent aphids. In addition, the LC25 significantly shortened the adult pre-oviposition period (APOP) and lengthened the total pre-oviposition period (TPOP) of avirulent aphids, while the mean generation time (T) was significantly increased. For the virulent aphid, sublethal exposure significantly lengthened development time of first and third instars, TPOP, and adult longevity. In addition, all demographic parameters of virulent soybean aphid were significantly affected when they were exposed to the LC25 of lambda-cyhalothrin. Conclusion Our results demonstrate lambda-cyhalothrin is less toxic to virulent aphids and exposure to the LC25 can trigger hormesis, which may have implications for the long-term management of this pest with this insecticide as well as with aphid-resistant varieties of soybean. © 2019 Society of Chemical Industry.

Chrysodeixis includens nucleopolyhedrovirus (ChinNPV: Baculoviridae: Alphabaculovirus) is an active ingredient of a biological-based insecticide (Chrysogen®) recommended against soybean looper (SBL), Chrysodeixis includens (Walker, [1858]), in soybean in Brazil. We investigated if SBL strains resistant to chemical insecticides are cross-resistant to the baculovirus ChinNPV. In droplet feeding bioassays, SBL strains resistant to lambda-cyhalothrin and teflubenzuron showed equivalent susceptibility to ChinNPV as heterozygous and susceptible strains, indicating no cross-resistance between ChinNPV and chemical insecticides in SBL. Therefore, the ChinNPV is a valuable new “mode-of-action” tool for SBL resistance management in Brazil.

During the application of pesticides on soybean fields, a vertical deposition gradient of the product can occur throughout the canopy, resulting in difficulties for controlling stink bugs that are in the middle and lower thirds of plants. This study aimed at evaluating the systemicity of thiamethoxam insecticide in different soybean phenological stages, using brown stink bugs as bioindicators of the pesticide efficacy. The study combined product application sites (lower, middle and upper third) and stink bugs infestation areas at five soybean phenological stages (R2, R3, R4, R5.2 and R6). For the R2 and R5.2 stages, plants presented acropetal translocation of the product, being the effect more evident in the R2 stage. For the R3, R4 and R6 stages, the product translocation was not sufficient for controlling the stink bugs. In all stages, for treatments with direct exposure (same infestation and spraying place), stink bugs were satisfactorily controlled.

The objective of this study was to evaluate the influence of adjuvants associated with the spray mixture of insecticides aimed at the control of Euschistus heros in the soybean crop. First the treatments were applied and later the cages were assembled, being artificially infested 10 insects per cage. The treatments were composed of the insecticide Engeo Pleno® in combination with different adjuvants. The surface tension was reduced in all the treatments that contained the addition of adjuvants, and the treatments with organosilicone were the ones that resulted in the lower levels. The treatments did not present a significant difference, however, a superior efficiency of the insecticide was observed in association with adjuvants. The addition of Assist®, Break Thru® S240 and TA35® adjuvants to the thiamethoxam + lambda-cyhalothrin insecticide improves the control of Euschistus heros, showing an agronomic efficiency superior to the insecticide applied alone. El objetivo de este estudio fue evaluar la influencia de los adyuvantes asociados a la mezcla de insecticidas en spray destinados al control de Euschistus heros en el cultivo de soja. Primero se aplicaron los tratamientos y posteriormente se ensamblaron las jaulas, siendo infestados artificialmente 10 insectos por jaula. Los tratamientos estuvieron compuestos por el insecticida Engeo Pleno® en combinación con diferentes adyuvantes. La tensión superficial se redujo en todos los tratamientos que contenían la adición de adyuvantes, y los tratamientos con organosilicona fueron los que resultaron en los niveles más bajos, los tratamientos no presentaron diferencia significativa, sin embargo se observó una eficiencia superior del insecticida en asociación con adyuvantes. La adición de adyuvantes Assist®, Break Thru® S240 y TA35® al insecticida tiametoxam + lambda-cihalotrina mejora el control de Euschistus heros, mostrando una eficiencia agronómica superior al insecticida aplicado solo. O objetivo deste trabalho foi avaliar a influência de adjuvantes associados à calda de inseticidas visando o controle de Euschistus heros na cultura da soja. Primeiramente os tratamentos foram aplicados e posteriormente as gaiolas foram montadas, sendo infestados artificialmente 10 insetos por gaiola. Os tratamentos foram compostos pelo inseticida Engeo Pleno® em combinação com diferentes adjuvantes. A tensão superficial foi reduzida em todos os tratamentos que continham a adição de adjuvantes, sendo que os tratamentos com organosiliconados foram os que resultaram nos níveis mais baixos. Os tratamentos não apresentaram diferença significativa, porém, foi observada uma eficiência superior do inseticida em associação com adjuvantes. A adição dos adjuvantes Assist®, Break Thru® S240 e TA35® ao inseticida tiametoxam + lambda-cialotrina melhora o controle de Euschistus heros, apresentando eficiência agronômica superior ao inseticida aplicado isoladamente.

Soybean looper (SBL), Chrysodeixis includens (Lepidoptera: Noctuidae), is one of the main lepidopteran pests of soybean and cotton crops. In this study, we selected a strain of SBL with resistance to lambda-cyhalothrin and evaluated the inheritance, fitness costs and cross-resistance to deltamethrin and cypermethrin. In inheritance pattern studies, SBL larvae were exposed to technical grade insecticides in topical bioassays. To investigate fitness costs, SBL strains were reared on artificial diet without insecticide and the survival, development and reproductive rates were evaluated. Estimated LD50 values of lambda-cyhalothrin for the susceptible and resistant strains were 0.0015 and 0.11 μg a.i./larva, respectively, indicating a resistance ratio (RR) of 73.3-fold. The LD50 values of heterozygous were 0.016 and 0.017 μg a.i./larva, suggesting an autosomal inheritance of resistance. On lambda-cyhalothrin sprayed-leaves, the resistant strain showed >85% survival. By contrast, heterozygous and susceptible strains had

O milho voluntário é considerado uma planta daninha quando sua emergência ocorrer durante o ciclo da cultura em sucessão, como é o caso de plantas de milho voluntário de híbridos Roundup Ready (RR) em lavouras implantadas com cultivares de soja RR. O objetivo deste estudo foi verificar o efeito da interferência de diferentes densidades de plantas de milho voluntário RR sobre a cultura da soja RR, bem como estimar o nível de dano econômico (NDE). Para isso, foi conduzido um experimento em campo em dois locais em esquema fatorial com quatro repetições; os tratamentos constaram de densidades de milho voluntário RR (0, 1, 2, 3, 4, 5, 6, 7 e 8 plantas por m-2) competindo em todo o ciclo da soja. As alterações na morfologia e nos componentes de rendimento se comportaram de forma diretamente proporcional ao incremento das densidades de milho voluntário, sendo a variável legumes por planta a mais intensamente afetada. A perda de rendimento da soja na maior densidade de competidor chegou a 58%. O NDE foi estreitamente dependente do custo de controle das plantas de milho voluntário, da expectativa de rendimento da cultura, da eficiência do herbicida e do preço recebido pelo produto colhido, sendo a expectativa de rendimento o fator mais impactante. Em todas as simulações, o NDE encontrado foi muito baixo, menor que 0,48 planta m-2, evidenciando a necessidade do uso de herbicidas no controle do milho voluntário RR mesmo em baixas densidades. Volunteer corn is considered a weed when its emergence occurs during the crop cycle in succession, as is the case of volunteer corn plants of hybrids of Roundup Ready (RR) in crops implanted with RR soybean cultivars. The objective of this study was to verify the effect of the interference of different RR plant densities on the RR soybean crop, as well as to estimate the level of economic damage (NDE). For this, a field experiment was carried out at two sites in a factorial scheme with four replications, the treatments consisted of densities of volunteer corn RR (0; 1; 2; 3; 4; 5; 6; 7 and 8 plants m-2) competing in the entire soybean cycle. The changes in morphology and yield components behaved directly proportional to the increment of volunteer corn densities, with the variable vegetables per plant being the most strongly affected. The loss of soybean yield at the highest competitor density reached 58%. NDE was closely dependent on the cost of control of volunteer corn plants, crop yield expectancy, herbicide efficiency, and the price received for the harvested product, with yield expectancy the most impacting factor. In all simulations, NDE was found to be very low, less than 0.48 plants m-2 evidencing the need of herbicides in the control of RR volunteer corn even at low densities.

A cultura do painço pelo seu rápido crescimento, tolerância a seca e ciclo curto, tem despertado atenção de produtores e técnicos como alternativa de rotação de cultura e formação de palhada para posterior semeadura da soja no sistema plantio direta em algumas regiões do Rio Grande do Sul. No entanto, são escassas as informações sobre a época de aplicação e doses de nitrogênio (N). Por isso, o objetivo desse trabalho, foi avaliar épocas de aplicação e doses de N na cultura do painço, sobre alguns parâmetros de planta e na produtividade final de grãos. O experimento foi desenvolvido na Universidade Federal de Santa Maria, Campus de Frederico Westphalen, no período de setembro a novembro de 2012. O delineamento experimental foi de blocos ao acaso, num esquema fatorial 4 x 4, com quatro repetições, sendo os tratamentos constituídos da combinação de quatro doses de N (0, 30, 60 e 90 kg ha-1) e quatro diferentes épocas de aplicação do N: todo na semeadura, 30% na semeadura e o restante 15 dias após a emergência (DAE),30% na semeadura e o restante 30 dias DAE, 30% na semeadura e o restante 45 dias DAE. Não houve resposta significativa quanto à época de aplicação de N na cultura do painço. Houve uma resposta significativa e linear na altura de planta, produção de matéria seca, diâmetro do colmo, comprimento da panícula e no rendimento final de grãos com o aumento nas doses de N. : Due to its rapid growth, drought tolerance and short cycle, the proso millet crop has attracted the attention of producers and technicians as an alternative to crop rotation and formation of straw for subsequent planting of soybean in no-tillage system in some regions of the state of Rio Grande do Sul (RS), Brazil. However, there is limited information on application times and rates of nitrogen (N). Therefore, the objective of this study was to evaluate application times and rates of N in proso millet crop, under some plant parameters and in the final grain yield. The experiment was conducted in the Universidade Federal de Santa Maria, campus of Frederico Westphalen, in the period of September to November2012. The experiment design was that of randomized blocks, in a4 x 4factorial design, with four replications. The treatments consisted of the combination of four rates of N (zero, 30, 60 and 90 kg ha-1) and four different application times of N: all at sowing, 30 % at sowing and the remaining15 days after emergence (DAE), 30 % at sowing and the remaining 30 days DAE, 30 % at sowing and the remaining45 days DAE. There was no significant response as regards the application times of Nin the proso millet crop. On the other hand, there was a significant and linear response in plant height, dry matter production, stem diameter, panicle length and in the final grain yield within crease in rates of N.

With the intensification of pig farming systems, in Brazil, the production of swine waste has increased considerably, leading to water and soil contamination, due to its improper release. Pig slurry composting is an alternative that can be used in order to avoid or reduce negative impacts, especially for producers with physically limited farm areas, or those who intend to increase the number of animals in their production units. This study aimed at evaluating the influence of pig slurry compost doses on the agronomic characteristics and grain yield of proso millet. A randomized blocks design experiment was installed with four replications and five treatments: control without fertilization, control with mineral fertilizer (NPK) and pig slurry compost doses (4.0 Mg ha-1, 8.0 Mg ha-1; 12.0 Mg ha-1). The pig slurry composting increased the dry matter yield, number of grains per plant and grain yield of proso millet, when compared to the control with or without mineral fertilizer. The proso millet yield, at the doses of 8.0 Mg ha-1 and 12.0 Mg ha-1 of pig slurry, was superior than for both the control without fertilization and the control with the recommended mineral fertilizer, with the latter reaching a maximum agronomic efficiency at the dose of 8.0 Mg ha-1. RESUMO Com a intensificação dos sistemas de criação de suínos, no Brasil, a produção de dejetos cresceu consideravelmente, provocando problemas de contaminação da água e solo, devido à sua aplicação inadequada. A compostagem de dejetos líquidos de suínos surge como alternativa para evitar ou reduzir impactos negativos, principalmente para produtores com limitação de áreas físicas, ou que visem ao aumento do número de animais na unidade de produção. Objetivou-se avaliar o efeito de doses de compostagem de dejetos líquidos de suínos nas características agronômicas e produtividade de grãos de painço. O delineamento experimental foi em blocos ao acaso, com quatro repetições e cinco tratamentos, os quais consistiram em testemunha sem adubação, testemunha com adubação mineral (NPK) e doses de compostagem de dejetos líquidos de suínos (4,0 Mg ha-1; 8,0 Mg ha-1; 12,0 Mg ha-1). A compostagem de dejetos líquidos de suínos promoveu incremento na produção de massa seca, número de grãos por planta e produtividade de grãos de painço, em relação às testemunhas sem adubação e com aubação mineral. A resposta do painço para produtividade, nas doses de 8,0 Mg ha-1 e 12,0 Mg ha-1, mostrou-se superior à das testemunhas sem adubação e com adubação mineral recomendada para a cultura, sendo que esta apresenta máxima eficiência agronômica para a dose de 8,0 Mg ha-1.

The objective of this study was to evaluate the effect of a foliar fungicide commonly used to control Asian soybean rust (Phakopsora pachyrhizi) in the physiological and sanitary quality of soybean seeds. The experiment was carried out during the 2012/13 field season, with six treatments and four replications arranged in a randomized complete block design. The following treatments were evaluated: T1 (no fungicide application); one application at R1 stage; two applications at R1 and R3 stages; three applications at R1, R3, and R5 stages; four applications at R1, R3, R5, and R6 stages and five applications at R1, R3, R5, R6 and R7 stages. Seeds yield, seed weight, viability and vigor assessments were used to measure the impact of foliar fungicide applications on soybean yield and seed quality. The results indicated that four fungicide applications provide higher grain yield, increased seed weight, and germination percentages within commercial standards. In contrast, the number of fungicide applications did not correlate with the sanitary quality of the seeds.

The objective of this study was to evaluate the behavior of brown linseed, submitted to different spacing between lines. The experiment was carried out at the Federal University of Santa Maria, Frederico Westphalen Campus, under a typical eutrophic Red Latosol, from September to December 2013. The experimental design was a randomized complete block design with four replications and four treatments, with experimental plots of 4.0 × 3.0 meters, totaling 12.0 m². The treatments consisted of four line spaces, 17, 34, 51 and 68 cm. The following parameters were evaluated: dry matter, plant height, stem diameter, weight of one thousand seeds and grain yield. The spacing of 0.17 m was the one that stood out showing higher yield and agronomic characteristics favorable to the crop, such as a smaller stature of important plant from the point of view of a lower lodging and a greater production of dry matter, and consequently residual straw for cultivation in succession, this being a basic premise in areas under no-tillage system.

This study aimed to evaluate the effect of different managements with pig slurry (PS) and cattle slurry (CS) on wheat dry matter and grain yields, and the potential to estimate this variation with the NDVI (normalized difference vegetation index) and NDRE (normalized difference red edge index) vegetation indices. The experiment was conducted in Frederico Westphalen-RS, Brazil, in a randomized block experimental design, in a 2 x 7 factorial scheme with four replicates and seven forms of surface and subsurface application, with and without the use of the dicyandiamide (DCD) nitrification inhibitor, distributed as follows: control without application of slurry and DCD; control without application of slurry and DCD, but scarified only with the injection machine; surface application; surface application with DCD; subsurface injection; subsurface injection with DCD; and application of NPK in mineral form. At flowering of the wheat crop, dry matter was collected and readings of NDVI and NDRE were taken, and finally grain yield was quantified. For PS and CS, best results of dry matter and grain yields were found in managements with subsurface injection and subsurface injection with DCD, respectively. Among the vegetation indices, only NDVI was efficient to estimate variations in the management using CS for wheat dry matter and grain yields. RESUMO Este estudo teve como objetivo avaliar o efeito de diferentes manejos com dejeto líquido de suíno (DLS) e bovino (DLB) na produtividade de matéria seca e de grãos da cultura do trigo e o potencial de estimativa dessa variação com os índices de vegetação NDVI (índice de vegetação da diferença normalizada) e NDRE (índice de vegetação da diferença normalizada pelo red-edge). O experimento foi conduzido em Frederico Westphalen, RS, no delineamento experimental blocos ao acaso, em esquema fatorial 2 x 7, com quatro repetições, sendo duas fontes (DLS e DLB) e sete formas de aplicação superficial e subsuperficial, com e sem o uso de dicianodiamida (DCD), ficando assim distribuídos: testemunha sem aplicação de dejetos e DCD; testemunha sem aplicação de dejetos e DCD, porém apenas escarificada com a máquina de injeção; aplicação dos dejetos em superfície; aplicação dos dejetos em superfície com DCD; injeção dos dejetos em subsuperfície; injeção dos dejetos em subsuperfície com DCD; e aplicação de NPK na forma mineral. No florescimento da cultura do trigo, realizou-se a coleta de matéria seca e as leituras de NDVI e NDRE, e por fim, quantificou-se a produtividade de grãos. Constatou-se que, para DLS e DLB, os melhores resultados em produtividade de matéria seca e de grãos foram para os manejos com injeção em subsuperfície e com injeção em subsuperfície com DCD respectivamente. Dos índices de vegetação, apenas o NDVI foi eficiente em estimar as variações no manejo para a fonte DLB para a produtividade de matéria seca e de grãos do trigo.