Abstract The present study aimed to investigate the response of soybean cultivars with different susceptibility levels to the root-knot nematode Meloidogyne javanica at varied time intervals by analyzing the initial plant–nematode interaction using antioxidant enzymes as oxidative stress markers. A 4 × 4 × 2 factorial method with 5 repetitions was used to analyze 4 soybean cultivars at 4 different collection times—6, 12, 24, and 48 h—with and without M. javanica inoculation. The parameters evaluated were the activities of antioxidant enzymes phenol peroxidase (POX) and ascorbate peroxidase (APX); the concentrations of hydrogen peroxide (H2O2) and malondialdehyde (MDA); and the number of M. javanica juveniles penetrated into each plant. H2O2 concentration varied among the cultivars with and without inoculation and at different collection times as indicated by MDA concentration and POX and APX activities, demonstrating a rapid response of the host to an infection by M. javanica. Oxidative stress caused by M. javanica did not vary among the soybean cultivars regardless of their susceptibility level; however, the antioxidant enzymes POX and APX responded according to the susceptibility level of the cultivars.

Abstract Weeds can be hosts of root-knot nematodes of the genus Meloidogyne. The importance of the species Meloidogyne morocciensis parasitizing many crops is recognized, but their reproductive capacity in weeds is not known. The present study hypothesizes the ability of M. morocciensis to parasitize and reproduce in different weed species found in Brazil. The objective was to evaluate the reproduction of M. morocciensis in 36 weed species. The plants were individually inoculated with 5,000 eggs and second stage juveniles and kept in greenhouse for 60 days. The experimental design was completely randomized with twelve replications. The root system of each plant was evaluated for gall index (GI), final nematode population (PF), number of nematode/g of root (NNGR) and reproduction factor (RF). It was verified that M. morocciensis has the capacity to parasite 36 weed species belonging to 16 different botanical families, confirming the hypothesis proposed. From the 36 species evaluated, 77.8% (28) were susceptible (FR ≥ 1.0) to M. morocciensis. The present study is the first to identify different weeds as hosts of M. morocciensis, evidencing its polyphagous habit, indicating species of plants with high capacity to multiply this nematode and that need more attention during the integrated management of these pathogen.

Abstract Meloidogyne javanica is among the most important nematodes that damage soybean, and although genetic resistance is the ideal control measure, there are few cultivars described as resistant among those recommended for southern Brazil. The objective of this work was to evaluate the reaction of soybean cultivars to M. javanica. The inoculum of nematodes (Est. J3) was obtained from soybean plants and inoculated into tomato plants cultivar “Santa Cruz”. Thirty-seven soybean cultivars widely used in the South, Southeast and Midwest of Brazil were used in the experiment. For each plant a suspension of 5,000 eggs + juveniles of second stage of M. javanica was inoculated into a sterile soil hole in 2-liter pots with six replications. The evaluation of root weight, number of galls, number of nematodes was 60 days after M. javanica inoculation. The results were subjected to analysis of variance, and the averages of each treatment were compared to each other by the Scott-Knott cluster test at 5% probability. Even though M. javanica presented RF> 1.00 in all soybean genotypes tested, different levels of susceptibility were observed. Thus, the lowest reproduction of the root-knot nematode was observed in M 5947 IPRO, HO AMAMBAY IPRO, BMX GARRA IPRO and FPS ATALANTA.

Abstract The effect of initial population density (Pi) of the peanut root-knot nematode, Melodoigyne arenaria, on curly leaf parsley growth was assessed in this study. The population densities of M. arenaria ranged from 0 to 64 eggs + second-stage juveniles (J2)/cm3 soil in sterile sandbags. The root gall index (RGI), reproduction factor (RF), fresh leaf weight (FLW), dry leaf weight (DLW), root fresh weight (RFW), root length (RL), leaf height (LH), and chlorophyll index (SPAD) were determined at 90 days after inoculation. FLW, DLW, RFW, LH, and SPAD data were fitted to the Seinhorst equation, y = m + (1 - m) zPi-T, to determine the tolerance limit T = 0.25 eggs +J2/cm3 soil for FLW, DLW, RFW, and LH, with relative means (m) of 0.52, 0.24, 0.22, and 0.4 respectively; conversely, the T value for SPAD was 0.125 eggs + J2/cm3 soil and with a m of 0.26. All biometric variables decreased with an increase in the initial population density (Pi). Nevertheless, the highest RF of M. arenaria in parsley was 78.92 for a Pi = 8 eggs + J2/cm3 soil, with an RGI value of 5 from Pi = 1 eggs + J2/cm3. Curly leaf parsley growth decreased with an increase in Pi of M. arenaria.

Resumen Se realizó él estudió del efecto de poblaciones crecientes (Pi) del nematodo de la agalla Melodoigyne arenaria en el cultivo de perejil crespo, que oscilaron entre 0 y 64 huevos + juveniles del segundo estadio (J2) /cm3 de suelo en bolsas com suelo estéril. A los 90 días después de la inoculación, se determinó, índice de agallamiento (IA), factor de reproducción (FR), peso fresco follaje (PFF), peso seco follaje (PSF), peso fresco raíz (PFR), longitud de raíz (LR) altura foliar (AF) e índice de clorofila (SPAD). Los datos de PFF, PSF, PFR, AF y SPAD se sometieron a la ecuación de Seinhorst, y = m+(1-m) zPi-T, que permitió determinar el límite de tolerancia T = 0.25 huevos +J2/cm3 de suelo para PFF, PSF, PFR y AF, con promedios relativos (m) de 0.52; 0.24; 0.22 y 0.4 respectivamente; por otro lado, el valor de T para SPAD fue de 0.125 huevos+J2/cm3 de suelo y con un m de 0.26. Todas las variables biométricas decrecen al incremento de las poblaciones iniciales (Pi). Asimismo, el mayor FR de M. arenaria en perejil es 78.92 para la Pi = 8 huevos +J2/cm3 de suelo, con un valor de IA de 5 a partir de Pi = 1 huevos+J2/cm3. Conforme se incrementa las Pi de M. arenaria el cultivo de perejil crespo reduce su crecimiento.

RESUMO A buva (Conyza bonariensis L.) é umas das principais plantas daninhas dos sistemas de cultivos conservacionistas, especialmente por sua evolução à resistência ao herbicida glyphosate. Os objetivos deste trabalho foram verificar a resposta de Conyza bonariensis suscetível (S) e resistente (R) ao glyphosate em diferentes estádios a herbicidas alternativos e avaliar o potencial fisiológico de sementes destes biótipos. Dois estudos foram realizados e repetidos, sendo o primeiro em casa de vegetação em esquema fatorial 2x3x10, sendo A: biótipos de buva (S e R); B: estádios de desenvolvimento (I (1-2 folhas), II (5-6 folhas) e III (30-35 folhas)) e C: herbicidas (glyphosate, chlorimuron-etílico, metsulfuron-methyl, diclosulam, amônio-glufosinato, paraquat, paraquat+diuron, diquat, 2,4-D além de testemunha não aplicada).O segundo estudo foi desenvolvido em laboratório, realizando-se avaliações do potencial fisiológico das sementes, a partir do por peso de mil sementes (PMS), germinação (G), primeira contagem da germinação (PG), índice de velocidade de germinação (IVG) e emergência (IVE), comprimento da parte aérea (CPA), raiz (CR) e total (CT), matéria seca da parte aérea (MSPA), raízes (MSR) e total (MST), testes de frio e envelhecimento acelerado. O biótipo CR foi eficientemente controlado pelos herbicidas alternativos ao glyphosate, utilizados até o estádio de 6 folhas. As sementes do biótipo CR apresentaram desempenho fisiológico superior em todas as variáveis analisadas, com maior tolerância a condições adversas em seu estabelecimento. O manejo de buva resistente a glyphosate demanda a utilização de estratégias que visem evitar a produção de novas sementes.

ABSTRACT Hairy fleabane (Conyza bonariensis L.) is a major weed of the conventional crop systems. Therefore, the objectives of the present study were to assess the responses of glyphosate-susceptible (S) and -resistant (R) C. bonariensis at various developmental stages and evaluate the physiological potential of seeds to propose alternative herbicides for the control of this weed. Two experiments were performed in replicates. The first experiment was performed in a greenhouse, arranged in a 2 x 3 x 10 factorial design. Specifically, two hairy fleabane biotypes (S and R) at different developmental stages (I, II, and III) were subjected to various treatments (glyphosate, chlorimuron-ethyl, metsulfuron-methyl, diclosulam, ammonium glufosinate, paraquat, paraquat+diuron, diquat, 2,4-D, and control). Percentage control was evaluated at 7, 14, 21, and 28 days after the application of the treatments (DAT), and shoot dry mass (SDM) was measured at 28 DAT. The second experiment was performed in a laboratory to evaluate the physiological potential of seeds based on the weight of 1000 seeds (TSW); shoot length (SL), radicle length (RL), total length (TL), fresh seedling mass (FSM), dry seedling mass (DSM), accelerated aging (AA) and cold test (CT), and germination (G) in response to cold and accelerated aging. The alternative herbicides tested effectively controlled biotype R up to the stage -I. Seeds of biotype R showed higher physiological potential in terms of all analyzed variables and exhibited greater tolerance to adverse conditions during seedling establishment. Therefore, strategies for the management of glyphosate-resistant hairy fleabane should aim at preventing new seed production.

ABSTRACT Pepper (Capsicum annuum) is an important crop in Peru and is negatively affected by the knot nematode. This studio's objective is to evaluate the reaction of three pepper varieties (Papri King, Papri Queen, and Bell pepper cv. 'Yolo Wonder') to Meloidogyne arenaria, M. incognita, and M. hapla. The experimental design was completely randomized into three pepper varieties and three Meloidogyne spp. with six replicates. The peppers were maintained in a plastic shade house, cultivated in polyethylene bags with 4 kg of sterilized sand, which were inoculated with 5000 eggs and juveniles (J2). At 90 days after inoculation, leaf height (LH), root length (RL), dry leaf weight (DLW), fresh root weight (FRW), chlorophyll index (SPAD), root gall index (RGI), and reproduction factor (RF) were evaluated. The results showed that all pepper varieties were susceptible to M. incognita, M. arenaria, and M. hapla. LH, RL, DLW, FRW, and SPAD all indicated a decrease in pepper growth and development, with the highest reduction, observed in the presence of M. incognita, followed by M. arenaria and M. hapla.

RESUMEN El pimiento (Capsicum annuum) es un cultivo importante en Perú y se ve afectado por el nematodo agallador. El objetivo de este estudio es evaluar la reacción de tres variedades de pimiento (Papri King, Papri Queen y Bell pepper cv. "Yolo Wonder") a Meloidogyne arenaria, M. incognita y M. hapla. El diseño experimental fue completamente al azar en tres variedades de pi miento y tres especies Meloidogyne spp. con seis réplicas. Los pimientos se mantuvieron en un espacio con sombra de plástico, cultivados en bolsas de polietileno con 4 kg de arena esterilizada, que se inocularon con 5000 huevos y juveniles (J2). 90 días después de la inoculación se evaluó la altura de hoja (AH), longitud de raíz (LR), peso de hoja seca (PHS), peso de raíz fresca (PRF), índice de clorofila (SPAD), índice de agallas de raíz (IG) y factor de reproducción (FR). Los resultados mostraron que todas las variedades de pimiento eran susceptibles a M. incognita, M. arenaria y M. hapla. AH, LR, PHS, PRF y SPAD indicaron una disminución en el crecimiento y desarrollo del pimiento, con la mayor reducción observada en presencia de M. incognita, seguido de M. arenaria y M. hapla.

ABSTRACT Chlorophylls and carotenoids are the main photosynthetic pigments in plants, and photosynthetic potential can be used to determine the nitrogen fixation or cycling capacity of cover crops. Therefore, this study quantified and compared the content of photosynthetic pigments in Raphanus sativus and Vicia sativa by using two different methods, namely the extraction method and measurements with a portable chlorophyll meter, and determined whether the results of these two methods showed a significant correlation. Photosynthetic pigments were measured, using both methods, in a greenhouse and laboratory, at four developmental stages: the vegetative stages I (30 days after sowing [DAS]), II (60DAS), and III (90DAS), and the reproductive stage (150DAS). The determination of the photosynthetic pigment content in R. sativus and V. sativa, obtained from the extraction method and chlorophyll index, revealed significant differences depending on the developmental stage in both species. Furthermore, the contents of chlorophyll a, chlorophyll b, and carotenoids determined using the extraction method showed high coefficients of correlation with the total chlorophyll index determined using the portable chlorophyll meter. Therefore, the portable chlorophyll meter can be used for the accurate evaluation of the photosynthetic potential of Raphanus sativus and Vicia sativa, which also saves time and reagents.

Abstract Currently, the cultivation of quinoa (Chenopodium quinoa) at Peru does not have studies related to the reaction of Meloidogyne spp. This study aimed to evaluate the reaction of five quinoa cultivars (‘Salcedo INIA’, ‘Choclito’, ‘Huariponcho’, ‘Negra Collana’, and ‘Kcancolla’) to Meloidogyne arenaria, Meloidogyne incognita, and Meloidogyne hapla. The experiment was carried out using a completely randomized design, with five quinoa cultivars and three species of Meloidogyne spp. with six repetitions. Quinoa plants were kept in a mesh house and placed in polyethylene bags with 3,000 dm³of sterile soil inoculated with 5,000 eggs + juveniles (J2). After 90 days of inoculation, the number of nematodes per gram of root, number of galls, and the reproduction factor (final population/initial population) were determined. All quinoa cultivars were susceptible to M. incognita and resistant to M. arenaria and M. hapla, except for ‘Negra Collana’, which was susceptible to M. arenaria, and ‘Salcedo INIA’’ and ‘Huariponcho’, susceptible to M. hapla.

Resumen Actualmente el cultivo de quinua (Chenopodium quinoa) en el Perú, no cuenta con estudios relacionados a la reacción de Meloidogyne spp. La investigación tuvo como objetivo evaluar la reacción de cultivares de quinua (‘Salcedo INIA’, ‘Choclito’, ‘Huariponcho’, ‘Negra Collana’ y ‘Kcancolla’) a Meloidogyne incognita, Meloidogyne arenaria y Meloidogyne hapla. Las plantas de quinua se manejaron en casa malla y fueron colocadas en bolsas de polietileno con 3.000 dm³ de suelo estéril, los cuales fueron inoculados con 5.000 huevos + juveniles (J2). Después de los 90 días de la inoculación, se determinó el número de nematodos por gramo de raíz, número de agallas y factor de reproducción (población final / población inicial). Todos los cultivares de quinua son clasificados como susceptibles a M. incognita, resistentes a M. arenaria y M. hapla a excepción de Negra Collana siendo considerado susceptible a M. arenaria, asimismo, ‘Salcedo INIA’ y ‘Huariponcho’ son considerados susceptibles a M. hapla.

Resumo O feijoeiro (Phaseolus vulgaris) é uma das principais culturas produzidas no Brasil. Sua produtividade é comprometida por diversas enfermidades, incluindo as causadas pelos nemátodes-das-galhas (NGR, Meloidogyne spp.). Três ensaios foram conduzidos em estufa com o objetivo de avaliar o comportamento de sete genótipos (C2-1-6-1-1, C4-8-1-1, PR11-6-4-1-2 Pr11-6-4-1-2, IAC-Alvorada, IAC-Diplomata e IAC-Una) de feijão a Meloidogyne incognita, M. javanica e M. enterolobii. O tomateiro (Solanum lycopersicum) cv. Rutgers foi utilizado como controlo para comprovar a viabilidade do inóculo. O delineamento experimental foi inteiramente casualizado, com oito tratamentos e cinco repetições por tratamento. Para a comprovação dos resultados, os três ensaios foram repetidos no tempo, seguindo a mesma metodologia. O solo foi inoculado com 5.000 ovos + juvenis de segundo estádio (J2) de cada espécie de nemátode por vaso. As variáveis, índice de galhas (IG) e de massas de ovos (IMO) e o fator de reprodução (FR) foram determinados 60 dias após a inoculação. Os genótipos de feijão C4-8-1-1 e C2-1-6-1-1 foram resistentes a M. incognita e a M. javanica, respectivamente. Nenhum genótipo foi resistente a M. enterolobii nos dois ensaios. Os restantes genótipos de feijão foram suscetíveis às espécies de nemátodes estudadas. Os genótipos resistentes (C4-8-1-1 e C2-1-6-1-1) poderão ser utilizados em áreas de cultivo infestadas com M. incognita e M. javanica, respectivamente, ou usados como fontes de resistência em programas de melhoramento genético.

Abstract Bean (Phaseolus vulgaris) is one of the main crops produced in Brazil. In growing areas, productivity has been committed by various diseases, including those caused by root-knot nematodes (Meloidogyne spp.). Three independent experiments were conducted in greenhouse to evaluate the behavior of seven genotypes (PR11-6-4-1-2, Pr11-6-4-1-2 , C4-8-1-1 C2-1-6-1-1, IAC-Diplomata, IAC-Alvorada and IAC-Una) and three bean cultivars (IAC-Diplomata, IAC-Alvorada and IAC-Una) to Meloidogyne incognita, M. javanica and M. enterolobii. The tomato Rutgers was used as control to confirm the inoculum viability. The experimental design was completely randomized with eight treatments and five replicates. To confirm the results, three experiments were repeated using the same methodology. The soil was inoculated with 5,000 eggs from each species of nematode per pot. As variables, gall (GI) and egg mass (EM) indexes and the reproduction factor (RF) were determined 60 days after inoculation. The genotypes C4-8-1-1 and C2-1-6-1-1 were resistant to M. incognita and M. javanica, respectively. No genotype were resistant to M. enterolobii in both assays. The other genotypes were susceptible to the nematode species studied. The resistant genotypes (C4-8-1-1 and C2-1-6-1-1) can be used in infested areas with M. incognita and M. javanica, respectively, or used as sources of resistance in breeding programs.

A cultura do feijão (Phaseolus vulgaris) tem a sua produtividade limitada por diversos fatores bióticos, sendo frequentemente afetada por nemátodes fitoparasitas. Várias espécies de nemátodes das galhas radiculares (NGR), Meloidogyne spp., têm sido encontradas e identificadas como sendo prejudiciais a esta cultura. Recentemente, Meloidogyne luci e Meloidogyne ethiopica foram reportadas como parasitas de feijoeiro no Brasil. O objetivo do trabalho foi avaliar, através da realização de ensaios de vaso, a reprodução de M. ethiopicae M. luci em vinte cultivares de feijoeiro. As plantas foram individualmente inoculadas com 5000 ovos + juvenis do segundo estádio (J2) de NGR e foram mantidas em estufa. Decorridos 60 dias da inoculação, as raízes de cada planta foram avaliadas quanto ao número de galhas, população final e fator de reprodução (FR=população final/população inicial). As médias das diferentes variáveis foram comparadas entre si pelo teste de agrupamento de Scott e Knott a 5%. Todas as cultivares de feijoeiro avaliadas comportaram-se como suscetíveis a ambos as espécies de NGR, com FR variando de 9,8 a 55,9 para M. ethiopica, e de 6,0 a 20,0 para M. luci.

The productivity of common bean crop is limited by several biotic factors, being often affected by plant-parasitic nematodes. Several species of root-knot nematodes (RKN), Meloidogyne spp. have been reported as damaging to the crop. Recently, Meloidogyne luci and Meloidogyne ethiopica were recorded parasitizing roots of common bean plants in Brazil. Therefore, the objective of this work was to evaluate the reproduction of M. ethiopica and M. luci on twenty bean cultivars. Plants were inoculated with 5,000 eggs plus second stage juveniles (J2) of RKN and pots were maintained in a greenhouse. Sixty days after inoculation, the roots of each plant were evaluated for number of galls, final population and reproduction factor (RF = final population / initial population) and the means of the different variables were compared by the Scott and Knott grouping test at 5%. Results showed that all tested cultivars were susceptible to both RKN, with RF ranging from 9.8 to 55.9 for M. ethiopica and from 6.0 to 20.0 for M. luci.

RESUMO Considerando-se que os nematoides são bastante sensíveis às intervenções antrópicas, estes organismos podem ser utilizados como indicadores de qualidade do solo (QS). Neste trabalho objetivou-se estudar atributos químicos, físicos e a nematofauna edáfica como indicadora de qualidade do solo em áreas de pastagem com aplicação sucessiva de dejetos líquidos de suínos (DLS) no Noroeste do estado do Rio Grande do Sul. Para tal, foram consideradas as diferentes áreas: pastagem de Azevém + Tifton com uso de DLS há 14 anos (A14), pastagem de Azevém + Tifton com uso de DLS há dois anos (A2) e mata nativa (MN), sendo analisados atributos químicos, físicos e a nematofauna do solo, com três repetições por tratamento, em delineamento blocos casualizados. Os atributos químicos do solo foram sensíveis às mudanças em áreas de pastagem com aplicação sucessiva de DLS, com aumento no teor de P, em comparação com a área MN e teor de MO do solo na área A14 semelhante ao encontrado na área MN. Em relação aos atributos físicos do solo, densidade e microporosidade aumentam com a aplicação sucessiva de DLS em áreas de pastagem de azevém+tifton, enquanto que a macroporosidade diminuiu, em comparação com as áreas MN. Os nematoides dos grupos Discocriconemella, Paratylenchus, Pratylenchus, Trichodorus, Tylenchus e de vida livre são eficientes como indicadores da qualidade do solo, uma vez que evidenciam alterações nos atributos químicos e físicos do solo entre as áreas de pastagem de azevém+tifton com uso sucessivo de DLS e em relação à mata nativa.

ABSTRACT Considering that nematodes are quite sensitive to anthropic interventions, these organisms can be used as indicators of soil quality (SQ). The objective of this work was to study chemical and physical attributes and soil nematode as an indicator of soil quality in pasture areas with successive application of pig slurry (PS) in the Northwest of the state of Rio Grande do Sul. For this, the different areas were considered: Azevém + Tifton pasture with PS use for 14 years (A14), Azevém + Tifton pasture with use of PS for two years (A2) and native forest (NF), with a chemical and physical attributes nematofauna of the soil, with three replicates per treatment, in a randomized complete block design. The soil chemical attributes were sensitive to changes in pasture areas with successive application of PS, with increase in P content, compared to the NF area and soil OM content in the A14 area similar to that found in the NF area. In relation to the soil physical attributes, density and microporosity increased with the successive application of PS in ryegrass + tifton pasture areas, while macroporosity decreased, compared to NF areas. The nematodes of the Discocriconemella, Paratylenchus, Pratylenchus, Trichodorus, Tylenchus and free-living groups were efficient as indicators of soil quality, since they were able to evidence alterations in soil chemical and physical attributes between the ryegrass + tifton use of PS and in relation to the native forest.

RESUMO Teve-se por objetivo neste trabalho avaliar a reação de genótipos de cana-de-açúcar a Meloidogyne javanica e Pratylenchus zeae. Mudas de cada material genético (‘RB008347’, ‘RB975944’, ‘RB987932’, ‘RB877935’, ‘RB855156’, ‘RB935744’, ‘RB996961’, ‘RB925345’, ‘RB935581’ e ‘RB966928’), obtidas da cultura de tecidos e mantidas em vasos com solo esterilizado, em casa de vegetação, foram inoculados com 5.000 ovos + juvenis de segundo estádio de M. javanica ou 1.600 P. zeae/planta, utilizando-se seis repetições por tratamento. Para controle e a comprovação da viabilidade do inoculo, utilizaram -se plantas de tomate 'Rutgers' e sorgo ‘BRS 506’ para M. javanica ou P. zeae, respectivamente. Decorridos 120 dias avaliou-se o número de galhas nas plantas inoculadas com M. javanica; a população final de nematoide e o fator de reprodução (FR) de ambos nematoides. A seguir, as médias das diferentes variáveis foram comparadas entre si pelo teste de agrupamento de Scott-Knott a 5%. Verificou-se que embora M. javanica e P. zeae tenham apresentado FR>1,00 em todos os genótipos de cana-de-açúcar testados, forma observados diferentes níveis de suscetibilidade. Desse modo, a menor reprodução do nematoide das galhas foi observada em ‘RB008347’, ‘RB877935’, ‘RB975944’ e ‘RB987932’; e de P. zeae em ‘RB987932’ e ‘RB966928’.

ABSTRACT The objective of this work was to evaluate the response of sugarcane genotypes to Meloidogyne javanica and Pratylenchus zeae. Sugarcane seedlings of the genotypes RB985944, RB987932, RB877935, RB855156, RB935744, RB996961, RB925345, RB935581 and RB966928 obtained from tissue cultures and maintained in pots with sterilized soil in a greenhouse were inoculated with 5,000 eggs + second- stage juveniles of M. javanica or 1,600 of P. zeae per plant, using six replicates per treatment. Tomato (Rutgers) and sorghum (BRS506) plants were used as control and proof of viability of the inoculum for the M. javanica and P. zeae, respectively. The number of root-knot in the plants inoculated with M. javanica, final nematode population and reproduction factor (RF) of both nematodes were evaluated at 120 days after inoculation. The averages of the different variables were compared by the Scott-Knott's clustering test at 5%. The nematodes M. javanica and P. zeae showed RF>1.00 in all sugarcane genotypes assessed, however, different levels of susceptibility were found. The lowest reproduction of the nematodes was found in the genotypes RB008347, RB877935, RB975944 and RB987932 (M. javanica) and RB987932 and RB966928 (P. zeae).

Este estudio tuvo como objetivo evaluar la proporción de biodiesel obtenido a partir de aceites de soja y girasol in natura y otros ya utilizados en procesos de fritura, así como verificar la viabilidad de su utilización a través del análisis horas máquina. El aceite de fritura fue colectado en restaurantes. Se realizaron diez repeticiones para cada origen (diez para aceite de soja in natura, diez para girasol in natura, diez para aceite de soja reutilizado y diez para aceite de girasol reutilizado). El biodiesel proveniente de cada tipo de aceite reutilizado (soja y girasol) fue testado en maquinaria agrícola (tractor New Holland - TL 65) para evaluación de horas máquina, utilizando 4 L de biodiesel cada 80 L de diesel, con tres repeticiones y testigo (diesel). A partir de los aceites in natura de soja y girasol se obtuvo una cantidad de 100 % de biodiesel. Con los aceites reutilizados en proceso de fritura, se logró una cantidad de biodiesel de 88,15 % para girasol y 88,00 % para soja. En los ensayos horas máquina, para el biodiesel proveniente de girasol reutilizado se alcanzó un promedio de consumo de 5,75 L/hora máquina, para el biodiesel de soja de 6,20 L/hora máquina y para diesel de 6,00 L/hora. A partir de los resultados obtenidos se comprobó que el biodiesel proveniente de aceite de fritura presenta viabilidad de producción y demuestra potencial para utilización en maquinaria agrícola, presentado óptimo desempeño.

This study aimed to assess the proportion of biodiesel derived from soybean oil and sunflower oil in nature and other already used in frying, and to verify the feasibility of using these oils by testing machine hours. The frying oil was collected in restaurants. Ten repetitions were performed for each oil origin (ten for in natura soybean oil, ten for in natura sunflower oil, ten for reused of soybean oil, and ten for reused sunflower oil). Biodiesels originated from each reused oil (soybean and sunflower) were tested in agricultural machinery (tractors New Holland TL-65) to evaluate hours machine, using 4 L of biodiesel each per 80 L diesel with three replications and a control (diesel). A hundred percent biodiesel was obtained from in natura soybean and sunflower oils. From the oils reused from frying processes, 88 % was obtained for soy, and 88.15 % for sunflower. In testing machine hours, for biodiesel derived from sunflower reused oil, the average was 5.75 L h-1 machine, for soybean biodiesel (6.20 L h-1), and for diesel (6.00 L h-1). These results show that biodiesel derived from cooking oil presents production feasibility, and has potential for use in agricultural machinery with optimal performance.

A qualidade fisiológica de sementes de feijão é influenciada pelo ambiente de produção e por práticas de manejo empregadas durante o cultivo. O objetivo do trabalho foi avaliar a produtividade e qualidade fisiológica de sementes de feijão, após aplicações de herbicidas dessecantes em diferentes épocas na pré-colheita. Utilizou-se o delineamento de blocos ao acaso, em esquema fatorial (3x3) + 1, onde se testou a aplicação de três herbicidas dessecantes: glyphosate (960 g de ia.ha-1), dicloreto de paraquat (240 g de ia.ha-1) e glufosinato de amônio (400 g de ia.ha-1) + óleo mineral, aplicados em três épocas (dias após o florescimento - DAF), mais uma testemunha sem aplicação de herbicida, em quatro repetições. A qualidade fisiológica das sementes foi determinada por meio dos testes de germinação, primeira contagem, índice de velocidade de emergência de plântulas, envelhecimento acelerado, condutividade elétrica e biomassa seca de plântulas. A produtividade de sementes não é influenciada pelos herbicidas e épocas de aplicação. Independente da época de aplicação, a menor percentagem de plântulas normais no teste de germinação, envelhecimento acelerado e primeira contagem, é de sementes dessecadas com o herbicida glufosinato de amônio. O herbicida glyphosate reduz o vigor de plântulas. As épocas de aplicação para o produto dicloreto de paraquat não afetam a germinação e o vigor das sementes de feijão.

The physiological quality of bean seeds is influenced by the production environment and management practices employed during cultivation. The objective of this study was to evaluate the productivity and physiological quality of bean seeds after desiccant applications at different times at pre-harvest. A randomized block design was used, with a factorial (3x3) + 1 arrangement, where the application of three desiccants was tested: glyphosate (960 g a.i. ha-1), paraquat dichloride (240 g a.i. ha-1) and glufosinate ammonium (400 g a.i. ha-1) + mineral oil, applied three times (days after flowering - DAF), and a control without herbicide in four replications. Seed quality was determined by the following tests: germination, first count, seedling emergence speed rate, accelerated aging, electrical conductivity and seedling dry biomass. Seed yield was not influenced by either herbicides or time of application. Regardless of time of application, the lowest percentage of normal seedlings after the germination, first count and accelerated aging tests was observed in seeds desiccated with the herbicide glufosinate ammonium. The herbicide glyphosate reduces seedling vigor. The times of application of the product paraquat dichloride did not affect the germination and vigor of bean seeds.

Objetivou-se nesse trabalho avaliar a produtividade e qualidade fisiológica de sementes de trigo, cultivar ‘Quartzo’, colhidas após a dessecação com dois dessecantes (glyphosate e paraquat) em dois estádios reprodutivos (11.2 e 11.3). O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial 3 x 2 (dois dessecantes e uma testemunha) e dois estádios fenológicos do trigo, com quatro repetições. Foram avaliados a produtividade de sementes, a massa de mil sementes e a qualidade das sementes (germinação, primeira contagem de germinação, comprimento de parte aérea e radicular, massa fresca e seca de plântulas, envelhecimento acelerado, condutividade elétrica, frio sem solo e lixiviação de potássio). Diante dos resultados obtidos, pode-se concluir que o uso de dessecantes na cultura do trigo nos dois estádios de desenvolvimento não interferiu na produtividade, mas influenciou negativamente na qualidade fisiológica de sementes. De forma geral, o glyphosate foi o que proporcionou menor efeito fitotóxico sobre as sementes, e as sementes obtidas com aplicação de dessecantes no estádio 11.2 foram de qualidade fisiológica superior às obtidas com aplicação no estádio 11.3.

This study aimed to evaluate the yield and seed quality of wheat, cultivar ‘Quartzo’, harvested after desiccation with two desiccants (glyphosate and paraquat) at two reproductive stages (11.2 and 11.3). The study used a randomized block experimental design in a 3 x 2 factorial arrangement (two desiccants and a control) and two growth stages of wheat, with four replications. The following were assessed: seed yield, thousand seed weight and seed quality (germination, first germination count, root and shoot weight, seedling dry and fresh weight, accelerated aging, electrical conductivity, cold germination, potassium leaching). Based on the results, it can be concluded that the use of desiccants on wheat at the two stages of development have not affected yield, but they have negatively influenced physiological seed quality. Generally, the herbicide glyphosate showed the lowest phytotoxic effect on seeds, and desiccant application at stage 11.2 resulted in higher physiological seed quality compared with application at stage 11.3.