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The objective was to evaluate the effect of inoculation with rhizobia associated with nitrogen fertilization on the growth and productivity of cowpea cultivars. The experiment was carried out using two native isolates and the BR3262 strain (recommended for cowpea) plus nitrogen fertilization (30, 60 and 90 kg N ha-1) and a control without fertilization and inoculation, and two cultivars of cowpea (BRS Guariba and Novaera). The experimental design was in randomized blocks, with four replications, in a triple factorial scheme (4 x 4 x 2). At flowering, the following parameters were evaluated: Plant height, stem diameter, shoot dry weight, SPAD Index, and number of nodules. At harvest, data on yield components were collected: Number of pods per plant, pod length, number of seeds per pod, mass of 100 grains and yield. Inoculation with rhizobia strains favors the reduction of nitrogen fertilization, resulting in increases in plant growth and yield. The native isolate UESB R5 resulted in the highest final profit and reduced costs with nitrogen fertilization for both cultivars. [ABSTRACT FROM AUTHOR]

The plant density is a relevant management practice to obtain high yields in soybean (Glycine max (L) Merrill). The tendency to decrease the plant population is increasing due to the high cost of seeds. Thus, the objective of the present study was to evaluate the agronomic performance of different soybean cultivars to the reduction in plant density in the North Plateau of Santa Catarina. The experimental design was randomized blocks arranged in split plots. In the main plots, five cultivars were evaluated: AS3590 IPRO, BMX Ativa RR, BMX Zeus IPRO, M5838 IPRO, and NS5445 IPRO. The subplots evaluated four population densities: 120,000 plants ha-1, 160,000 plants ha-1, 200,000 plants ha-1 and the control (density indicated by the cultivar holder). Grain yield evaluations and their components were performed and the data was submitted to analysis of variance using the F test. When significant, the means of the main effects were compared by the Tukey test. In case of interaction, the means were then compared by regression analysis. Both comparisons were at the 5% significance level. The reduction in plant population did not affect the number of pods per area, the number of grains per pod, the harvest index, and grain yield. On the other hand, reducing plant density increased the number of pods on the branches and per plant. Therefore, the tested soybean cultivars supported reductions in plant population without affecting grain yield and productivity. In this way, reducing plant density can be recommended for soybean cultivated in the North Plateau of Santa Catarina. [ABSTRACT FROM AUTHOR]

A utilização de fontes nitrogenadas que reduzam perdas de N pode ser uma estratégia de manejo adequada para aumentar a sustentabilidade econômica e ambiental no cultivo do milho. Este trabalho foi conduzido com o objetivo de avaliar os efeitos de fontes e doses de nitrogênio sobre a produtividade de grãos do milho e a lucratividade da lavoura. O experimento foi conduzido a campo, em dois anos agrícolas, num Nitossolo Vermelho de textura argilosa. O delineamento experimental foi de blocos ao acaso, dispostos em parcelas subdivididas. Na parcela principal foram testadas quatro fontes de N: ureia convencional, ureia protegida, ureia com inibidor de nitrificação e ureia com inibidor de urease. Nas subparcelas foram testadas quatro doses de nitrogênio: 0, 140, 280 e 420 kg de N ha-1. As quatro fontes de fertilizantes nitrogenados não apresentaram diferenças no rendimento de grãos. A produtividade de grãos variou de 3,2 a 15,9 Mg ha-1. Ela apresentou uma resposta quadrática ao aumento da dose, independentemente da fonte de N. As doses teóricas que otimizaram a produtividade de grãos foram de 407 e 411 kg N ha-1 em 2016/2017 e 2017/2018, respectivamente. Os maiores índices de lucratividade foram obtidos pela aplicação das doses de 378 kg de N ha-1 com ureia convencional em 2016/2017 e 278 kg de N ha-1 de ureia com inibidor de uréase em 2017/2018.

A densidade de plantas é uma prática de manejo relevante para obtenção de altas produtividades na cultura da soja (Glycine max (L) Merrill). A tendência de diminuir a população de plantas é crescente devido ao alto custo das sementes. Desta forma, o objetivo do presente estudo foi avaliar o desempenho agronômico de diferentes cultivares de soja à redução na densidade de plantas no Planalto Norte Catarinense. O delineamento experimental foi de blocos ao acaso dispostos em parcelas subdivididas. Nas parcelas principais foram avaliadas cinco cultivares: AS3590 IPRO, BMX Ativa RR, BMX Zeus IPRO, M5838 IPRO e NS5445 IPRO. Nas subparcelas foram avaliadas quatro densidades populacionais: 120.000 plantas ha-1, 160.000 plantas ha-1, 200.000 plantas ha-1 e a testemunha (densidade indicada pela detentora da cultivar). Foram realizadas avaliações de rendimento de grãos e seus componentes e os dados submetidos a análise de variância utilizando teste de F. Quando significativas, as médias dos efeitos principais foram comparadas pelo teste de Tukey, e em caso de interação, as médias foram comparadas por análise de regressão. Ambas as comparações foram ao nível de significância de 5%. A redução na população de plantas não afetou o número de vagens por área, o número de grãos por vagem, o índice de colheita e o rendimento de grãos. Por outro lado, a redução na densidade de plantas aumentou o número de vagens nos ramos e por planta. As cultivares de soja testadas suportaram reduções na população de plantas, sem afetar o rendimento de grãos e a produtividade. Desta maneira, a redução na densidade de plantas pode ser recomendada para a soja cultivada no Planalto Norte Catarinense.

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O balanço hídrico do solo tem sido objeto de estudo por vários anos, devido ao detalhamento das informações geradas e que auxiliam no entendimento da disponibilidade de água no solo às plantas, no desenvolvimento das culturas agrícolas e, consequentemente, na produtividade das mesmas. O principal objetivo desse trabalho foi avaliar a dinâmica do balanço hídrico para a cultura da soja [Glycine max (L) Merrill.) submetida a diferentes níveis de déficit hídrico e seu impacto na produtividade da cultura. O experimento foi conduzido no interior de uma cobertura móvel (Rainout shelter), onde foram testados quatro tratamentos com diferentes níveis de déficit hídrico: T1 (Sem déficit hídrico), T2 (Déficit hídrico leve), T3 (Déficit hídrico moderado) e T4 (Déficit hídrico severo). Utilizou-se o delineamento experimental inteiramente casualizado, com três repetições. As variáveis do balanço hídrico como evapotranspiração da cultura (ETc), irrigação, precipitação, escoamento, e variação da água disponível no solo (ΔASW) foram monitoradas diariamente. Os resultados demostram uma influência dos diferentes níveis de irrigação deficitária e as condições meteorológicas sobre os componentes do balanço hídrico, o ciclo da cultura, características morfológicas e componentes de rendimento. Observou-se redução no rendimento de grãos com o aumento do déficit hídrico, do tratamento sem déficit para o déficit severo, de 42 a 11,5%, respectivamente, para o ano 1 e 2.

Evaluate the ideal doses of nitrogen fertilizer on wheat crops, in addition to avoiding unnecessary costs, assists in sustainability of the production system. The objective was to evaluate the effect of nitrogen (N) doses on the biomass and grain productivity, and the correlation between the normalized difference vegetation index (NDVI), biomass at flowering and grain yield, in wheat crop. The experiment was carried out in the experimental area of UFRGS, in Eldorado do Sul, in 2017 and 2018, under randomized block, with four replications. The treatments consisted of N doses at sowing (0, 15, 30 e 45 kg de N ha-1) and in topdressing (2017 - 0, 20, 40, 60 e 80 kg de N ha-1 and 2018 - 0, 40 e 80 kg de N ha-1). The wheat cultivars BRS Parrudo and TBIO Toruk were used. The treatment with 30 and 45 kg de N ha-1 applied at sowing combined with 80 kg de N ha-1 applied in topdressing, were those that obtained the highest yields of both grain and biomass, for both years and cultivars. The correlation between NDVI and biomass and grain yields were high for both years and cultivars. [ABSTRACT FROM AUTHOR]

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Salicylic acid (SA) is a plant growth regulator and participates in several physiological and biochemical processes. Its use can assist in the growth, development, productivity and quality of several crops. Thus, the objective of this work was to evaluate the effect of salicylic acid in two application stages on wheat crop. The experiment was conducted under field conditions and designed as randomized blocks, with four replications. Treatments 0.5 and 1.0 mM of SA were applied in stages 1 and 10, beginning and end of vegetative growth of wheat plants, besides a control treatment (without SA). Phytointoxication and SPAD index evaluations were performed at 14, 21, 28, and 35 days after application (DAA) of SA and the end of the experiment, 109 DAA the plants were tracked to quantify the mass of a thousand grains, hectoliter weight and grain yield. The application of SA did not cause symptoms of phytointoxication and increased the values of the SPAD index and all components of grain yield compared to the control treatment (without SA). The application of SA promoted a greater increase in the variables analyzed when applied in stage 10 of wheat plants. [ABSTRACT FROM AUTHOR]

In recent years, paddy rice growers from the south of Santa Catarina, Brazil, have anticipated the sowing date to the beginning of September, aiming to harvest the crop ratoon. In addition to that, they have increased the sowing density to mitigate the smaller plant growth. The objective of this work was to analyze the effects of sowing time and density on the agronomic performance of pregerminated rice. The experiment was set in the city of Praia Grande, SC, Brazil, during the 2018/2019 growing season. A randomized block design was used, with treatments arranged in split plots. Three sowing dates were tested in the main plots: September 10 (early sowing), October 15 (preferential sowing), and November 20 (late sowing). Four sowing densities were evaluated in the split plots: 80 kg, 120 kg, 160 kg, and 200 kg of seeds per hectare. Morphological characteristics and the yield and components of grains were assessed. Grain yield ranged from 6,277 kg ha-1 to 9,605 kg ha-1 and was affected by the interaction between sowing date and density. The highest yield was achieved when rice was sowed on October 15 at the density of 120 kg ha-1. On the earliest sowing date, grain yield increased linearly by 12.54 kg ha-1 for each kg of added seed above the lowest density evaluated in the trial. The highest grain productivity achieved on this sowing date was 7,858 kg ha-1. Plant density had a small impact on rice yield at the latest sowing date. The highest yield at this planting time (8,546 kg ha-1) was gathered at the density of 120 kg ha-1. The optimum seed density to maximize pregerminated rice yield in the south of Santa Catarina depends on the sowing date and is higher when the crop is sowed early. [ABSTRACT FROM AUTHOR]

Este trabalho foi conduzido objetvando identfcar as bases morfológicas e fsiológicas para as diferenças de produtvidade registradas em duas regiões produtoras de arroz irrigado do estado de Santa Catarina (SC). Os experimentos foram conduzidos em campo nos municípios de Itajaí e Pouso Redondo, SC, utlizando o sistema de cultvo pré-germinado. Em cada local foram testados cinco genótpos de arroz irrigado. Avaliaram-se os caracteres área foliar do colmo principal, incidência de doenças, teor de clorofla da folha bandeira, rendimento de grãos e seus componentes. A produtividade média dos cinco genótpos foi de 11,4t.ha-1 em Pouso Redondo e de 9,7t.ha-1 em Itajaí. O número de grãos por panícula foi o componente do rendimento que melhor explicou as diferenças de produtvidade registradas entre locais. A maior área foliar do colmo principal, o maior teor de clorofila da folha bandeira e a menor incidência de doenças foram característcas morfofsiológicas que contribuíram para a maior produtvidade. A maior disponibilidade de radiação, os menores valores da temperatura atmosférica máxima e a menor umidade relatva do ar são característcas ambientais que provavelmente contribuem para o maior rendimento de grãos do arroz irrigado em Pouso Redondo.

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O objetivo do trabalho foi estudar a adaptabilidade e a estabilidade fenotípica de dez genótipos de soja em doze ambientes no Paraná com o uso dos modelos AMMI (Additive Main Effects and Multiplicative Interaction Analysis) e Eberhart e Russel. Os ensaios foram conduzidos em blocos completos casualizados com três repetições na safra 2010/2011 em quatro locais no Estado do Paraná (Assaí, São Pedro do Ivaí, Cornélio Procópio e Marilândia do Sul) e em três épocas de semeadura (15/10/10 - 20/10/10; 29/10/10 -03/11/10; 15/11/10 - 20/11/10). As cultivares testadas, todas com a tecnologia RR, foram: SYN 1049; SYN 1152; SYN 1059; SYN 3358; SYN 1163; SYN 1157; V-MAX; FT Campo Mourão; BMX Potência; e, SYN 9070. O caráter analisado foi rendimento de grãos. Os dados foram submetidos à análise de variância. Posteriormente realizou-se a análise de adaptabilidade e estabilidade. Os modelos AMMI e Eberhart e Russel foram parcialmente concordantes apenas para parâmetro de estabilidade. A análise AMMI foi capaz de capturar 66% da variação associada aos resíduos não aditivos, os quais 43,18% estavam retidos no primeiro componente principal de interação e 23,58% no segundo componente os quais são suficientes para explicar a interação G×E. Os genótipos SYN 1059, SYN 1163 e V-MAX destacam-se pela produtividade consideravelmente superior e ampla adaptação produtiva. A cultivar SYN 1163, na análise AMMI, mostra-se promissora entre as demais cultivares lançadas comercialmente pelo alto desempenho de rendimento de grãos, adaptação e previsibilidade de resposta.

Cereais de inverno com duplo-propósito demonstram ser uma excelente alternativa para a sustentabilidade do sistema de integração lavoura-pecuária no Sul do Brasil. O presente trabalho teve por objetivo avaliar a produtividade do trigo de duplo propósito BRS Tarumã, submetido a diferentes números de cortes. As variáveis avaliadas foram: matéria seca da forragem, teor proteico da forragem, rendimento de grãos, peso hectolitro e massa de mil grãos. Observou-se correlação positiva entre o número de corte com o rendimento e o peso hectolitro e correlação negativa para massa de mil sementes. A variável massa seca mostrou-se mais produtiva com a utilização de dois cortes. O teor proteico não foi influenciado pelos cortes. Conclui-se que o trigo cv. Tarumã é uma opção para produção de forragens e de grãos para o Oeste de Santa Catarina.

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Copyright of Revista Agrotecnologia is the property of Universidade Estadual de Goias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Agrotecnologia is the property of Universidade Estadual de Goias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to evaluate the physiological quality and the crop performance of soybean seeds submitted to the industrial and the conventional seed treatment process. Soybeans seeds of the cultivars FPS Urano RR, Syn 1059 RR and Syn 1163 RR were treated with Standak Top® (Pyraclostrobin + Thiophanate-methyl + Fipronil) at the dose of 200 mL 100kg-1 of commercial product + 100 mL 100kg-1 of the polymer. The treatments consisted of control, conventional and industrial treatment. In the field, we evaluated the emergence, the dry mass and the grain yield in two times of sowing. Seed coverage and physiological quality of seeds (germination tests, first count of germination and seedling emergence) were evaluated at the laboratory after treatment and at 30, 90 and 150 days of storage. Conventional and industrial seed treatment does not affect the germination of high vigor seeds (Cultivars Syn 1059 and Syn 1163) and increases the percentage of normal seedlings in low vigor seeds (Cultivar FPS Urano). The industrial and conventional seed treatment improve the emergence of the soybean crop and potentiates grain yield in soybean cultivars of high physiological quality. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the productive performance of soybean crops, in response to the use of seeds from lots with increasing vigor levels. The study was developed during the 2014/2015 and 2015/2016crops. In the first period, 14 treatments were evaluated, consisting of two factors, two genotypes (Syn 1059RR and NK7059RR), and seven seed lots. In the second seven treatments were considered, involving one genotype (Syn 1158RR) and seven seed lots. In both crop years, seed lots had vigor levels of 65, 70, 75, 80, 85, 90 and 95%, as determined by the accelerated aging test. The experiment was performed in a randomized block design, with a factorial scheme and five replications. Plant height, yield components, and grain yield were assessed throughout the culture cycle. The reflex of seed vigor in crop performance depended on the genotype employed. Also, there was an increase in both vegetative and reproductive performances of the crop as a function of seed vigor level. In this sense, every percentage point augmented in the vigor level of the lots resulted in a grain yield expansion of up to 28 kg.ha-1. [ABSTRACT FROM AUTHOR]

The increase in the concentration of atmospheric CO2 is one of the main environmental variables that can affect the production of cultivated plants. The objective of this study was to evaluate the effects of increase the atmospheric CO2 concentration on morphological and grain yield characteristics of wheat. For this, wheat plants of cultivar Marfim were cultivated under two CO2 concentrations (400 or 700 μmol mol-1). The variables evaluated were: gas exchange, morphological alteration and grain yield components. The increases in the CO2 concentration significantly altered the gas exchange parameters, increased anthocyanin index, plant height, leaf area, dry mass of leaves and roots. In regarding to yield, plants at 700 μmol mol-1 produced high number of grains per ear, high weight of thousand grains, high hectoliter weight (PH) and total production. Thus, the increase in atmospheric CO2 concentration influenced the agronomic performance of wheat through physiological alteration, biomass gain and increase in the grains yield. [ABSTRACT FROM AUTHOR]

O deficit hídrico e a deficiência nutricional são os principais fatores limitantes da produtividade da cultura do milho. Nesse sentido, objetivou-se com este estudo, avaliar os componentes de rendimento e a produtividade de grãos de híbridos de milho em função de níveis de adubação e de deficit hídrico em dois estádios fenológicos. O estudo foi realizado em casa de vegetação com a utilização de vasos com capacidade de 15 L. Utilizou-se delineamento de blocos casualizados em esquema fatorial (3 x 4 x 3) com três repetições. Os fatores foram constituídos por híbridos de milho (P30F53, AS1551 e AG5011), níveis de adubação (0; 0,5; 1 e 1,5 vezes a dose recomendada) e deficits hídrico (sem deficit, deficit no pendoamento (VT) e no enchimento de grãos (R2). Foi avaliado a altura de plantas, diâmetro de colmo, número de espigas, comprimento de espigas, massa seca e produtividade de grãos. Independente do híbrido e para todas as variáveis avaliadas a cultura do milho é mais sensível ao deficit hídrico no pendoamento do que no período de enchimento de grãos. O híbrido AS1551 foi o que apresentou maior produtividade de grãos, assim como, se destacou como o mais tolerante ao deficit hídrico e nutricional. A ausência de aplicação de NPK restringiu severamente a produtividade de grãos da cultura do milho, sendo que com o incremento dos níveis de adubação houveram significativos aumentos de produtividade. A correta fertilização do solo nos híbridos AS1551 e AG5011 mitigou os efeitos do deficit hídrico quando aplicado no estádio de enchimento de grãos.

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The objective was to evaluate the efficiency of inoculation based on the bacteria Azospirillum brasilense, in wheat crop performance with increasing nitrogen rates, in temperate conditions. The experiment was conducted on the wheat crop in a no-tillage system at the Federal University of Santa Catarina - Brazil, over two years (2013 and 2014). The experimental design was randomized blocks, in a 3x4 factorial model, with four replicates, combining three forms of wheat inoculation (seed inoculation, no inoculation, and leaf inoculation) with four N rates (0, 75, 150 and 225 kg ha-1 of N). A joint analysis of experiments (two assessment years) was used. Biometric parameters and yield components were evaluated. There was no three-way relationship among the factors. Inoculation effect was only significant for ear length and plant height, with different response accordingly to assessment year. The effect of N rate was a quadratic response for all variables. Inoculation showed inconsistent results, with an increase in plant height. The best results for the variables were with the application of 150 to 225 kg N ha-1. The application of 215 kg N ha-1 with no inoculation resulted in the best management for wheat cultivation. [ABSTRACT FROM AUTHOR]

This study sought to evaluate the effects of sources and splitting of nitrogen on the morphological parameters and yield of genetically modified maize hybrids. This study was conducted during 2012/2013 and 2013/2014 growing seasons in Tenente Portela, Rio Grande do Sul, Brazil. Randomized blocks design in factorial arrangement (2 x 2 x 11 x 3) were used for the growing seasons; seasons x maize hybrids x nitrogen management x nitrogen sources, with three replicates. Analysis of variance pointed to interaction between all factors through plant height and number of kernels per row. Significant interaction through season x maize hybrids x nitrogen management for ear insertion height and grain yield. The interaction seasons x nitrogen management x nitrogen sources, and maize hybrids x nitrogen management can be highlighted for the variable ear insertion height. The characteristic thousand grain weight showed interaction through seasons x maize hybrids. Maize hybrids respond similarly to nitrogen management, where different nitrogen sources show similar behavior for the studied variables, without response to grain yield. The different nitrogen management forms caused positive effects on the evaluated variables, especially when performed in the early stages of culture. The current recommendation of nitrogen splitting in maize is adequate, but for the hybrid DKB 250 VT PRO2 ® in water deficit, nitrogen can be applied until the V8 growth stage. [ABSTRACT FROM AUTHOR]

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The Bean is one of the basic foods of the Alagoas region, for presenting a high energy potential and rich source of protein. In Brazil, this source of food has significantly increased the exploitation of this culture of great agricultural importance. In this way, the aim of this work was to evaluate the performance of Phaseolus bean cultivars to the climate and soil conditions of the municipality of Arapiraca-AL. The experiment was realidado during the period from June to October 2014 (1st cycle) and June to October 2015 (2 ° cycle), consisting of 33 treatments in three repetitions, being evaluated the length, weight and number of grains of five pods. When analyzing the sample data it can be found that the genotypes showed significant differences for all the variables analyzed. In the first cycle, the cultivation of pearl presented superiority among the other varieties in qualitative terms, and could be indicated for the region of the wild Alagoano. The cultivar CNFC 10408 was considered the least suitable for the rugged region of Alagoas. The other genotypes showed no difference to the weight of pods and the number of grains of the pods. In the second cycle, the cultivars CNFC 11953, CNFC 11951, Pearl and CNFC 11952, were shown for the rugged region of Alagoas. [ABSTRACT FROM AUTHOR]

Nitrogen fertilization strategies using increasing dosages demonstrate favorable effects on grain yield and quality; however, differences in results have been reported in relation to the effect of dosages, times and application schedules throughout the development cycle of the crop. The objective of this study was to evaluate the productivity and protein quality characteristics in response to nitrogen fertilization management applied to the cultivars TBIO Itaipu, TBIO Pioneiro, TBIO Quartzo and TBIO Seleto. The experimental design in randomized blocks with three replications, in a factorial scheme (4 cultivars x 7) handlings was used. The experiment was conducted in Coxilha, RS, during the agricultural years of 2012 and 2013. The total dose of N used in the present work was 140 kg ha-1, with 30 kg ha-1 of N being applied at sowing and remainder in coverage, for the time defined in each treatment. The grain yield of the studied cultivars was increased with the nitrogen fertilization applied in a concentrated way in the treatment T2 and showed a negative correlation with the protein content, showing that the genotypic superiority to the yield of grains can negatively affect the protein ratio. Of the cultivars studied TBIO Pioneiro stood out from the others regarding the general gluten strength in the 2012 crop and the TBIO Seleto was superior in the 2013 crop, however, the protein content did not show a significant association with the gluten strength, revealing that the concentration was not efficient to predict industrial quality. [ABSTRACT FROM AUTHOR]

Canola stands out as an important economic alternative as it is a source for the production of oil for human consumption, and in its use for the production of biodiesel. However mechanized harvesting is an obstacle to the expansion of the cultivation of this brassicaceae that need to be solved. The objective of this work was to evaluate five canola mechanized harvesting management systems, with or without the application of a sealant, compared to losses of preharvest and harvest, grain yield and water content in the grains. The canola hybrid Hyola 61 was used, being seeded with row spacing of 0.45 meters, and density of 40 viable seeds m-2. The treatments resulted from the combination of different management processes combined with a sealant. The adopted managements were: M1- harvesting with cut straight to the natural maturation point (untreated); M2 - previous chemical desiccation with diquat; M3 - previous chemical desiccation with ammonium glufosinate; M4 - cut-windrowing, and M5 - ethefom application. The harvest managements with cut-windrowing, previous chemical desiccation, and applying etefom, singly or in combination to sealant, reduced the grain losses in the harvest allowing higher yields to be obtained, and also reducing the water content in the grains, under conditions of excessive rainfall. [ABSTRACT FROM AUTHOR]

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O uso de inoculantes na cultura do milho tem sido cada vez mais valorizado, em vista dos benefícios que pode trazer à cultura, como a fixação biológica do nitrogênio e o aumento da quantidade de raízes. Isto pode melhorar a absorção de água e nutrientes pela planta, contribuindo para o desenvolvimento do milho, principalmente em períodos de seca. Este estudo foi desenvolvido com o objetivo de avaliar, em condições de campo, as características agronômicas e o rendimento de grãos de híbridos de milho, inoculados, ou não, com uma mistura de três espécies de Azospirillum (A. brasilense, A. lipoferum, A. oryzae). Foram avaliados o teor relativo de clorofila nas folhas, a altura de planta, a senescência foliar, os componentes de rendimento de grãos, o teor de N, a matéria seca da parte aérea das plantas e o número mais provável de bactérias diazotróficas na rizosfera das plantas. A inoculação manteve o teor de clorofila significativamente maior até o estádio R3 das plantas, para os três híbridos testados, aumentou o rendimento da matéria seca da parte aérea, dos híbridos AS 1575 e SHS 5050, o peso de 1000 grãos, para o híbrido P32R48 e altura, para o AS 1575. Houve interação entre os genótipos de milho e as bactérias inoculadas, visto que, cada híbrido testado respondeu de forma diferente à inoculação. A inoculação de Azospirillum em milho demonstrou estimular o desenvolvimento das plantas no período vegetativo, aumentando a probabilidade de obter-se um estande de plantas uniforme, maior resistência ao estresse e maior concentração de clorofila nas folhas.

This study investigated the effects of soil management systems, tillage, and application of gypsum agricultural to soil, on soybean development in lowland areas. The experiment was carried out on an Alfisol in a randomized complete block design in a factorial arrangement. The two soil tillage practices were without deep tillage and with deep tillage. Gypsum treatments were no gypsum application, 500kg of gypsum ha-1, 1000kg of gypsum ha-1, and 1500kg of gypsum ha-1. Deep tillage resulted in less soil resistance to root penetration during ryegrass cultivation during the soybean offseason, 11 months after applying the management treatments, resulting in higher dry mass of ryegrass in the offseason and higher soybean yield in the following year. [ABSTRACT FROM AUTHOR]

The objective of this research was to evaluate how the management of nitrogen fertilization in corn and irrigation rates affects the nitrogen dynamics in the soil profile and corn grain yield. For this, was evaluated an experimental area which has been cultivated in no-tillage system since 22 years ago, in Eldorado do Sul/RS. Treatments consisted of the combination of nitrogen management in coverage (control without nitrogen topdressed, single application of 300 kg ha-1 and this dose splitted in two times) and irrigation rates (20 and 100 mm). Soil samples were taken ten days after the first fertilizer nitrogen in coverage and ten days after the second fertilizer N in coverage. Regardless of the rate, irrigation promoted the increase in nitrate content in subsurface layer (20-30 and 30-40 cm) after the application of nitrogen cover doses. The nitrogen splitted fertilization is an effective alternative to reduce the nitrate content in subsurface soil layers, for both irrigation rates. However, this is not reflected in higher yields and economic returns when compared to single application of nitrogen, regardless of the irrigation rate. [ABSTRACT FROM AUTHOR]

The cowpea crop is one of the greatest social, economic and nutritional importance of the Colombian Caribbean. The aim of the study was to select cowpea genotypes on base adaptability and stability parameters. Nine genotypes were evaluated in six representative environments of the Colombian humid Caribbean, during the years 2013 and 2014. Agronomic evaluation of genotypes was made under a randomized complete block design with nine treatments and four replications in all environments. For this study, the variables grain yield, number of grains per pod and weight of 100 seeds were evaluated. The adaptability and stability of the genotypes were evaluated by means of Wricke, Eberhart and Russel, Lin and Binns, and Carneiro methods. The combined analysis of variance detected highly significant differences (p<0,001) between environments, genotypes and genotype x environment interaction for the three variables studied. Three of the four methods applied identified the genotype L-042 as the best stability and adaptability to environmental conditions evaluated. The L-042 and L-019 lines showed yields higher than 1000 kg.ha-1, which makes them very promising for the Colombian humid Caribbean. The L-042 line was released as a new cultivar, with the name of CAUPICOR 50. [ABSTRACT FROM AUTHOR]

O objetivo deste trabalho foi avaliar o efeito de doses do regulador de crescimento trinexapac-ethyl e níveis de adubação nitrogenada sobre o desempenho agronômico e rendimento de grãos de três cultivares de trigo. O delineamento experimental foi de blocos ao acaso, em esquema fatorial, com três repetições, sendo: duas doses de adubação nitrogenada (60 e 120 kg ha-1), três cultivares de trigo (BRS 208, BRS 220 e BRS Guamirim), quatro doses de trinexapac-ethyl (0, 70, 140 e 210 g i.a. ha-1) e duas safras agrícolas (2008 e 2009). Na microrregião de Pato Branco, a dose de 60 kg ha-1 é suficiente para maximizar o potencial de rendimento de grãos dos cultivares avaliados. Independentemente da estatura dos cultivares, o regulador de crescimento não apresentou efeito positivo sobre o rendimento de grãos, com efeito negativo na presença de menor disponibilidade hídrica.

Considerando-se a importância da produção do arroz irrigado no Estado do Rio Grande do Sul e que o seu desempenho é influenciado pelas condições meteorológicas, o objetivo deste trabalho foi estimar a produtividade de grãos dessa cultura em função da radiação solar global e da temperatura mínima do ar, usando procedimentos de análise de regressão linear simples e múltipla. Realizou-se um experimento de campo, em Capão do Leão, RS, durante três anos agrícolas. Empregaram-se, em cada ano agrícola, seis datas de semeadura e oito cultivares de diferentes grupos de comprimento de ciclo. Dez colmos principais de cada cultivar foram marcados, para determinarem-se os principais estádios de desenvolvimento. A variável dependente (Y) foi a média da produtividade de quatro repetições, de cada época de semeadura, e as variáveis independentes foram: a média da radiação solar global (X¹), a média da temperatura mínima do ar (X²) e a média da temperatura mínima do ar elevada ao quadrado (X³), computadas em quatro períodos de desenvolvimento da planta para a radiação solar global e em três períodos para a temperatura mínima do ar. A maioria das variáveis, quando testadas isoladamente, apresentou uma relação linear significativa com a produtividade, mas os coeficientes de determinação (r²) foram mais elevados nas regressões lineares múltiplas envolvendo as principais variáveis. Modelos de regressão que utilizam como variáveis preditoras a radiação solar global e a temperatura mínima do ar, em diferentes períodos de desenvolvimento da planta, mostram-se adequados para a estimativa da produtividade de grãos de arroz irrigado.Considering the importance of irrigated rice production in the State of Rio Grande do Sul and that its performance is influenced by the weather conditions, the objective of this study was to estimate the grain yield of this crop as a function of global solar radiation and minimum air temperature using procedures of linear simple and multiple regression. A field experiment was conducted at the district of Capão do Leão, State of Rio Grande do Sul, Brazil, during three growing seasons. Six sowing dates and eight cultivars of distinct groups of cycle lengths were used in each crop season. Ten main culms of each cultivar were marked to determine the main stages of development. The dependent variable (Y) was the average grain yield of four repetitions of each sowing date and the independent variables were: the average of global solar radiation (X¹), the average minimum air temperature (X²) and the average of squared minimum air temperature (X³), computed for four periods of plant development for global solar radiation and for three periods for minimum air temperature. Most of the variables, when tested isolately, presented a significant linear relationship with grain yield, but the coefficients of determination (r²) were higher in multiple linear regressions involving the main variables. Regression models that use global solar radiation and minimum air temperature in distinct physiological periods of plant development as predicting variables, are suitable for estimating grain yields of irrigated rice.

A consorciação com a gliricídia controla as plantas daninhas do milho. Com o objetivo de entender melhor esse controle, realizou-se uma análise do crescimento do milho em consorciação com a gliricídia. O híbrido duplo AG 1051 foi cultivado com capinas (duas capinas, aos 20 e 40 dias após a semeadura), sem capinas e em consorciação com a gliricídia. Na consorciação, a gliricídia foi semeada a lanço, com 25 sementes viáveis m-2, por ocasião da semeadura do milho, entre as fileiras desta cultura. Utilizou-se o delineamento de blocos completos casualizados com parcelas subdivididas e oito repetições. O controle de plantas daninhas foi aplicado às parcelas, e as 13 coletas da parte aérea das plantas, para avaliação da área foliar e da matéria seca, às subparcelas. As coletas foram feitas de sete em sete dias, a partir dos 14 dias após a semeadura. Pode ser concluído que o controle das plantas daninhas com duas capinas determinou maiores valores na área e matéria seca foliares, bem como na matéria seca total da planta. Nessas características, as plantas das parcelas consorciadas apresentaram comportamento intermediário entre plantas das parcelas capinadas e das não capinadas. Portanto, as plantas daninhas reduzem o crescimento do milho, e a gliricídia provavelmente controla parcialmente o mato, beneficiando o milho. Não houve diferenças entre tratamentos de controle de plantas daninhas nas taxas de crescimento absolutas e relativas, área foliar específica e taxa assimilatória líquida. A maior razão de área foliar foi observada com a consorciação com gliricídia.The maize/gliricidia intercropping is known to control weeds. The aim of this work was to carry out a growth analysis of maize intercropped with gliricidia, to better evaluate the weed control. The double-hybrid AG 1051 was used and the crop was managed with three weed control procedures: (a) no-weeding; (b) two manual-weedings (at 20 and 40 days after seeding); and (c) maize intercropped with gliricidia, whose seeds were evenly spread by hand between maize rows just after maize sowing, using 25 seeds m-2. The experiment was a randomized complete block design, arranged in split-plots with eight replications. Weed control was applied to the plots, with the subplots consisting of ten plant samplings to evaluate leaf area and shoot dry matter yield. Maize shoot samplings were collected every seven days, 14 days after sowing. The control of weeds with two weedings resulted in higher values in area and leaf dry matter, as well as in total plant dry matter. Regarding these traits, the plants of the intercropped plots showed intermediate behavior between plants of weeded plots and plants of non-weeded plots. Therefore, weeds reduce the growth of maize while gliricidia probably partially controls the weeds, benefiting maize. There were no differences between treatments for weed control regarding absolute growth rates and relative growth rates, specific leaf area, and net assimilation rate. The highest leaf area ratio of maize was observed with gliricidia intercropping.

A gliricídia (Gliricidia sepium) é leguminosa perene, cultivada para propósitos múltiplos, que apresenta crescimento rápido e várias substâncias com propriedades alelopáticas. Existem indicações de que a consorciação com gliricídia também pode trazer benefícios no controle das plantas daninhas do milho. O objetivo deste trabalho foi avaliar o controle das plantas daninhas no milho (híbrido duplo AG 1051) com gliricídia em consorciação. Utilizou-se o delineamento em blocos completos casualizados, com oito repetições. Os tratamentos consistiram em: cultivo do milho com capinas (duas, aos 20 e 40 dias após a semeadura), sem capinas e em consorciação com a gliricídia. A gliricídia foi semeada a lanço, com 25 sementes m-2, por ocasião da semeadura do milho, entre as fileiras deste. Quinze espécies de plantas daninhas foram catalogadas na área experimental, sendo Commelina benghalensis a mais frequente. Os rendimentos de espigas verdes (empalhadas e despalhadas) obtidos com a consorciação foram iguais ou superiores a 85% dos rendimentos obtidos com capinas. Além disso, o rendimento de grãos no consórcio chegou a 80% do rendimento de grãos do milho capinado. Portanto, a consorciação com a gliricídia pode ser uma alternativa viável para as produções de milho verde e de grãos, embora essa consorciação não tenha influenciado a densidade e a biomassa seca das plantas daninhas.Gliricidia (Gliricidia sepium), a perennial leguminous species presenting fast growth and several allelopathic substances, is cultivated for multiple purposes. There are good evidences that gliricidia intercropped with maize efficiently controls weeds. This work aimed to evaluate the use of gliricidia intercropped with maize as a method of weed control in maize (hybrid AG 1051). The experiment was carried out in a randomized complete block design with eight replications. The treatments consisted of: maize cropping with hand-hoeing weed control (at 20 and 40 days after sowing); no weed control; and intercropping with gliricidia. Gliricidia was sown in-rows using 25seedsm-2 after maize sowing. Fifteen weed species were found and classified in the experimental area, with the most frequent one being Commelina benghalensis. Green ear yield (with husk and without husk) obtained with intercropping was equal to, or greater than 85% of the yields obtained with weeding. In addition, the grain yield from intercropping reached 80% of grain yield of the corn weeded. Therefore, intercropping maize-gliricidia may be a viable alternative for the production of green corn and grain, although it did not influence the density and dry biomass of the weeds.

The release of wheat cultivars with different nutritional demands and yield potential hinders generalized recommendations for nitrogen fertilization. This study was designed to evaluate the effects of different nitrogen fertilization levels (0, 60, 120 and 180 kg ha-1 of N) on the agronomic performance of six wheat cultivars (Triticum aestivum L.) in two harvests. A randomized block factorial design with three replications was used. The response to fertilization levels was evaluated through AMMI (Additive Main effects and Multiplicative Interaction) and GGE (Genotype main effects and Genotype x Environment interaction) biplot graphic methodologies and polynomial regression. There was genetic variability in response to nitrogen fertilization in the cultivars studied. The biggest increases in yield were observed under a more suitable water regime. The higher performance of yield components was associated with higher nitrogen fertilization levels.O lançamento de cultivares, com diferentes exigências nutricionais e potencial produtivo inviabilizam recomendações generalizadas de adubação nitrogenada para a cultura do trigo. O objetivo do presente trabalho foi de avaliar os efeitos de doses de adubação nitrogenada (ausência de fertilização, 60, 120 e 180 kg ha-1 de N) sobre o desempenho agronômico de seis cultivares de trigo (Triticum aestivum L.), em duas safras agrícolas. O delineamento experimental foi em blocos ao acaso em esquema fatorial, com três repetições. A resposta às doses empregadas foi avaliada através das metodologias em gráfico biplot AMMI (Additive Main effects and Multiplicative Interaction) e GGE (Genotype main effects and Genotype x Environment interaction) e regressão polinomial. Há variabilidade genética quanto à resposta a adubação nitrogenada, no conjunto de cultivares avaliados. Os maiores incrementos em produtividade ocorreram em condições mais adequadas de precipitação pluvial. O maior desempenho dos componentes do rendimento foram associados às maiores doses de adubação nitrogenada.

Popcorn is widely consumed in the south of Minas Gerais; however, up to now no specific breeding program for the region has been carried out. Recurrent selection (RS) is a viable alternative for breeding of this crop; nevertheless, it is necessary to frequently evaluate the progress achieved. Consequently, the purpose of this work was to assess the genetic progress obtained after two cycles of RS for the traits of popping expansion (PE) and grain yield (GY). Cycles one and two of the UFLA - E and UFLA - R populations, the original population (UFLA) and two controls were assessed. The experiment was conducted at the UFLA experimental farm in a randomized block design with eleven replications; ten agronomic traits, including PE and GY, were assessed. Gains from selection for the traits studied were observed, as well as that the type of kernel had an influence on the response for genetic progress for the PE trait and that the populations assessed exhibited potential for future selection cycles.O milho-pipoca é amplamente consumido no Sul de Minas Gerais, entretanto, até o momento, nenhum programa de melhoramento especifico para a região foi conduzido. A seleção recorrente (RS) é uma alternativa viável para o melhoramento da cultura, todavia faz-se necessário verificar frequentemente o progresso obtido. Por conseguinte, objetivou-se avaliar o progresso genético obtido após dois ciclos de RS para os caracteres capacidade de expansão (PE) e rendimento de grãos (GY). Foram avaliados os ciclos um e dois das populações UFLA - E e UFLA - R, a população original (UFLA) e duas testemunhas. O experimento foi conduzido na fazenda experimental da UFLA, no delineamento em blocos ao acaso com onze repetições, dez características agronômicas incluindo PE e GY foram avaliadas. Constataram-se ganhos com a seleção para os caracteres estudados, que o tipo de grão (pérola e espinho) influenciou na resposta do progresso genético para o caráter PE e que as populações avaliadas apresentam potencial para futuros ciclos seletivo.

O trabalho foi conduzido na Área Experimental do Setor de Melhoramento Genético de Plantas do Centro de Ciências Agrárias da Universidade Federal de Alagoas (SMGP-CECA-UFAL), objetivando-se avaliar o desempenho de genótipos de milho em diferentes densidades de semeadura. Foram avaliados quatro genótipos de milho, sendo três desenvolvidos pelo SMGP-CECA-UFAL e um desenvolvido pela EMBRAPA, em três densidades de semeadura: 50.000, 62.500 e 83.333 plantas.ha-1 . Foi usado o delineamento em blocos casualizados com três repetições. As variáveis avaliadas foram: Diâmetro do Colmo (DC), Altura de Inserção de Primeira Espiga (AIPE), Altura de Planta (AP), Porcentagem de Prolificidade (PROL), Porcentagem de Plantas Acamadas (PPA), Comprimento de Espiga (CE), Diâmetro de Espiga (DE), Número de Fileiras de Grãos (NFG), Peso de Cem Grãos (PCG), Rendimento de Espigas com Palha (REP) e Rendimento de Grãos (RG). Não houve diferença significativa entre os genótipos avaliados para as seguintes variáveis: DC, PPA, CE, DE, PCG, REP e RG. Os genótipos desenvolvidos pelo SMGP-CECA-UFAL apresentaram um excelente desempenho para todas as variáveis estudadas, especialmente no rendimento de grãos, com uma produtividade média de 6.379,00 kg.ha-1. A densidade de semeadura de 83.333 plantas por hectare promoveu um maior rendimento de grãos com 7.888,96 kg.ha-1. Performance of alagoanos genotypes of maize in different planting densities Abstract: The work was conducted in the Experimental area of the Setor de Melhoramento Genético de Plantas do Centro de Ciências Agrárias da Universidade Federal de Alagoas (SMGP-CECA-UFAL), aiming to evaluate the performance of genotypes of maize in different planting densities. Four corn genotypes were evaluated, being three developed by SMGP-CECA-UFAL and one developed by EMBRAPA, in three seeding densities: 50,000, 62,500 and 83,333. plants ha-1. Experimental design was used in randomized blocks with three replications. The variables evaluated were: Culm Diameter (DC), Time of First insertion Cob (AIPE), plant height (AP), percentage of Prolificacy (FAVOUR), percentage of Plants Jumble (PPA), Tang (EC) Length, diameter of the cob (DE), number of grain Rows (NFG), weight of 100 grains (PCG), yield of Spikes with straw (REP) and grain Yield (RG). There was no significant difference between the genotypes evaluated for the following variables: DC, PPA, CE, DE, PCG, REP and RG. The genotypes developed by SMGP-CECA-UFAL presented an outstanding performance for all variables studied, especially in grain yield, with an average productivity of 6,379 .00 kg.ha-1. The sowing density of plants per hectare 83,333 promoted a greater yield of grain with 7,888.96 kg ha-1.

The objective in this study was to evaluate the effects of nitrogen rates in association with rates of the growth retardant trinexapac-ethyl on wheat. The experiment was conducted in Viçosa, MG and arranged in a 5×4 factorial, randomized block design, with four repetitions. A combination of five nitrogen rates (30, 60, 90, 120 and 150kg ha-1) with four rates of trinexapac-ethyl (0, 62.5, 125 and 187.5g ha-1) were tested. Trinexapac-ethyl promotes reduction of soot dry mass and grain yield at the lowest N rates, but at the highest N rates there is increase in these characteristics. The combination between N and trinexapac-ethyl rates that promotes higher shoot dry mass is 150kg ha-1 and 187g ha-1 but that promotes higher grain yield is 100kg ha-1 and 120g ha-1, respectively.O objetivo neste estudo foi avaliar os efeitos de doses de nitrogênio associadas às doses do redutor de crescimento trinexapac-etil na cultura do trigo. O experimento, conduzido em Viçosa-MG, seguiu um esquema fatorial 5×4, no delineamento experimental de blocos casualizados, com quatro repetições. Os tratamentos foram 30, 60, 90, 120 e 150kg ha-1 de N, combinados com 0, 62,5, 125 e 187,5g ha-1 de trinexapac-etil. Trinexapac-etil promove redução da massa seca da parte aérea e do rendimento de grãos nas menores doses de N, mas sob doses elevadas de N o trinexapac-etil promove aumento dessas características. A combinação entre doses de N e trinexapac-etil que promove maior massa seca da parte aérea é de 150kg ha-1 e 187g ha-1, mas a que promove maior produção de grãos é de 100kg ha-1 e 120g ha-1, respectivamente.

Although labor is intensive, evaluating the growth of crops may allow a better understanding of crop performance, including the reasons why certain cultivars can compete better with weeds. This study aims at evaluating growth, green ear yield, and grain yield in corn when in competition with weeds. Cultivars AG 1051 and BRS 106 were grown with (two hoeings, at 20 and 40 days after sowing) or without weed control. In order to evaluate crop growth, six collections of the above-ground part and the root system of corn were performed, every 15 days, with the first collection made 30 days after sowing. A randomized complete block design was adopted, with split-split plots (weed control in plots, cultivars in subplots, and collections in sub-subplots) and ten replicates. Eighteen weed species were found in the experiment area. Increased values of corn leaf area, above-ground part and root system, due to plant age function, were smaller in non-hoed plots than in hoed plots and were dependent upon cultivar. The lack of weed control increased dry matter of weeds aboveground part and decreased green ear yield and grain yield. Cultivar AG 1051 had higher increases in leaf area, above-ground part of the plant and root system, due to plant age function, and controlled weeds better than cultivar BRS 106. In addition, cultivar AG 1051 was superior to other cultivars with respect to most traits used for green corn yield and grain yield assessment.A avaliação do crescimento das culturas, embora trabalhosa, pode possibilitar o melhor entendimento do desempenho das culturas, inclusive das razões pelas quais determinadas cultivares são capazes de competir melhor com as plantas daninhas. O trabalho teve como objetivo avaliar o crescimento e os rendimentos de espigas verdes e de grãos do milho, em competição com plantas daninhas. As cultivares AG 1051 e BRS 106 foram cultivadas com duas capinas (aos 20 e 40 dias após a semeadura) e sem controle de plantas daninhas. Para avaliação do crescimento da cultura, foram realizadas seis coletas da parte aérea e do sistema radicular do milho, de 15 em 15 dias, a primeira sendo efetuada 30 dias após a semeadura. Utilizou-se o delineamento de blocos completos casualizados, com parcelas sub-subdivididas (controle de plantas daninhas nas parcelas, cultivares nas subparcelas e coletas nas sub-subparcelas) e dez repetições. Dezoito espécies de plantas daninhas ocorreram na área experimental. Os aumentos da área foliar, da parte aérea e do sistema radicular do milho, em função da idade, foram menores em parcelas não capinadas do que nas parcelas capinadas e dependeram das cultivares. A falta de controle das plantas daninhas aumentou a matéria seca da parte aérea das plantas daninhas e reduziu os rendimentos de espigas verdes e de grãos. A cultivar AG 1051 apresentou maiores aumentos da área foliar, da parte aérea da planta e do sistema radicular, em função da idade da planta, e controlou melhor as plantas daninhas, que a cultivar BRS 106. Além disso, a cultivar AG 1051 foi superior à outra cultivar, quanto à maioria das características utilizadas na avaliação do rendimento de milho verde e quanto ao rendimento de grãos.

There has been interest in reducing the use of herbicides for weed control in order to decrease environmental degradation problems. The objective of this study was to evaluate the effects of gliricidia planting density sown by broadcasting and intercopping on green ear and corn grain yield as well as on weed control. A randomized block design with split-plots and five replicates were adopted. Cultivars AG 1051, BM 2022, and BM 3061, assigned to plots, were submitted to the following treatments: no hoeing, two hoeings (at 20 and 40 days after sowing), and intercropped with gliricidia sown at densities of 10 and 20 seeds m-2. Thirty weed species occurred in the experiment area, with Cucumis anguria as the most frequent ones. Cultivar BM 2022 was the best for the total number of ears (TNE) and number (NMHE) and weight of marketable husked ears. Together with cultivar AG 1051, this cultivar had the highest total weight and marketable unhusked ear weight (MUEW). However, the cultivars did not differ with respect to grain yield (GY). The highest green ear and corn grain yield and weed control percentages were obtained with two hoeings; in MUEW, NMHE and GY, intercropping provided intermediate means in comparison with those obtained in hoed and non-hoed plots, indicating that gliricidia was partially beneficial to corn. Increased gliricidia seeding density heightened the benefits to corn (TNE and MUEW). The lack of hoeing produced the poorest green ear and grain yields.Existe interesse na redução do uso de herbicidas, visando-se a diminuição de problemas de degradação ambiental. O objetivo do trabalho foi avaliar os efeitos da densidade da gliricídia, semeada a lanço e em consorciação, sobre os rendimentos de espigas verdes e de grãos do milho e sobre o controle de plantas daninhas. Utilizou-se o delineamento de blocos ao acaso com parcelas subdivididas e cinco repetições. As cultivares AG 1051, BM 2022 e BM 3061, plantadas nas parcelas, foram submetidas aos seguintes tratamentos: sem capinas, duas capinas (aos 20 e 40 dias após a semeadura) e consorciação com a gliricídia, semeada nas densidades de 10 e 20 sementes m² . Trinta espécies de plantas daninhas ocorreram na área experimental, sendo Cucumis anguria a mais frequente. A cultivar BM 2022 foi a melhor quanto ao número total de espigas (NTE) e número (NEDC) e peso de espigas despalhadas comercializáveis. Essa cultivar apresentou, juntamente com a cultivar AG 1051, os maiores pesos total e de espigas empalhadas comercializáveis (PEEC). Todavia, as cultivares não diferiram quanto ao rendimento de grãos (RG). Os maiores rendimentos de milho verde e de grãos e de controle das plantas daninhas foram obtidos com duas capinas; a consorciação propiciou em PEEC, NEDC e RG médias intermediárias às obtidas nas parcelas capinadas e nãocapinadas, indicando que a gliricídia foi parcialmente benéfica ao milho. O aumento da densidade de semeadura da gliricidia aumentou os benefícios para o milho (NTE e PEEC). A ausência de capinas propiciou os piores rendimentos de espigas verdes e de grãos.