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The objective of this work was to evaluate the agronomic performance and water use efficiency of crop rotations under conventional system (CTS) and no-tillage system (NTS) through two experiments conducted in the Semiarid region of the northern state of Minas Gerais, Brazil. Experiment 1 consisted of a grain corn-common bean rotation, and experiment 2 consisted of a sorghum-sweet corn rotation. The treatments, in both experiments, consisted of two tillage systems (CTS and NTS) arranged in strip-plots, in two crop years, with ten replications. Yield and production components of all crops and water use efficiency (WUE) of crops grown in the autumn-winter seasons were evaluated within each crop rotation. The data obtained were subjected to analysis of variance and, when significant, the means were subjected to the F test at 5% significance level. The results obtained showed that the NTS increases corn yield in 21.45% in the grain corn-common bean rotation; however, the common bean yield present no difference between tillage systems. NTS increases the sorghum fresh and dry matter yields in 39.65% and 84.26%, respectively, in the sorghum- sweet corn rotation, and the sweet corn total and commercial ear yield in 11.99% and 21.80%, respectively. The NTS increases the WUE of crops grown in the autumn-winter season, in both crop rotations. RESUMO Objetivou-se com esse trabalho avaliar o desempenho agronômico e a eficiência do uso da água de sistemas de sucessão de culturas em preparo convencional (PC) e plantio direto (PD), em dois experimentos instalados na região norte de Minas Gerais. O experimento 1 foi constituído pelo plantio em sucessão de milho- grão / feijão-comum, e o experimento 2 constituído pelo plantio em sucessão de sorgo / milho-verde. Em ambos os experimentos, os tratamentos foram constituídos por dois sistemas de manejo (PC e PD), dispostos no esquema de faixas, em dois anos de cultivo, com dez repetições. Foram avaliadas a produtividade e os componentes de produção de cada cultura, além da eficiência no uso de água (EUA) pelas culturas instaladas nas safras de outono-inverno, dentro de cada sistema de sucessão. Os dados obtidos foram submetidos à análise de variância, e, no caso de significância, as médias foram estudadas pelo próprio teste F a 5% de significância. Os resultados obtidos permitiram concluir que na sucessão milho-grão / feijão-comum, o PD aumenta a produtividade do milho em 21.45%, contudo, não há diferença entre os manejos para a produtividade feijão- comum. Na sucessão sorgo / milho-verde, o PD proporciona aumento da produtividade da matéria verde e matéria seca de sorgo em 39.65 e 84.26%, respectivamente, enquanto que no cultivo do milho-verde, o PD aumenta em 11.99 e 21.80%, respectivamente, a produtividade de espigas totais e comerciais. Nos dois sistemas de sucessão, o PD proporciona aumento na EUA pelas culturas, nas safras de outono-inverno.

Sorghum is one of the most drought-tolerant cereals. However, strong water stress, especially during the reproductive phase, causes significant grain yield reduction. Drought events are common in second crops planted after soybean harvest in Brazil. The objective of the present study was to assess grain sorghum hybrids grown under pre- and post-flowering drought stress. Twenty-five hybrids were subjected to two water stress environments (pre- and post-flowering) and one environment with non-water stress. The experimental design was a split plot based on a randomized complete block with three replicates. Water stress pre-flowering reduced plant height, accelerated flowering, and increased panicle index compared with water stress post-flowering. Both pre- and post-flowering stress reduced yield, by 45% and 48%, respectively. Grain mass was greatly affected by stress occurring post-flowering but not by that occurring pre-flowering. Therefore, the reduction in yield caused by pre-flowering stress is due more to the reduction of grain number in the panicle, whereas the reduction when stress occurs post-flowering is due more to reduction in grain size. The plant chlorophyll index decreased when stress occurred pre-flowering and reverted after irrigation had resumed, demonstrating recovery in the photosynthetic capacity of the sorghum plant. With post-flowering stress, the chlorophyll index decreased significantly 30 days after the stress, affecting grain filling, with consequent yield loss

This study aimed to determine the size and shape of experimental plots that provide maximum precision using relative information method. This trial was conducted at the Federal Institute of Bahia. Plant height, cladode length, cladode width, cladode thickness, cladode area, cladode area index, number of cladodes, cladode total area and yield were measured in the third production cycle, 930 days after planting. The plants, defined as basic units, were arranged in 39 plot sizes so that the crop would fill the whole experimental area. Then, plot shapes with higher relative information and equal plot size in basic units were selected. The experimental plot with eight basic units in size ensures higher efficiency in the experimental evaluation. This combination between size and shape, besides meeting all evaluation requirements of the characteristics normally assessed in studies with forage cactus pear, has the maximum control of soil heterogeneity, thereby decreasing experimental error and significantly increasing precision.

In the current scenario of climate change, sorghum crop has high growth potential, requiring adaptation and selection studies for the various Brazilian production environments. Sorghum is among the most drought-tolerant cereals; however, extended summer can reduce the size and number of grains in the plant, reflecting into poorer yields. Sorghum breeding programs aim to develop hybrids more tolerant to water deficit, to ensure profitable yield even in the face of drought stress. The objective of the present study was to evaluate the effects of water restriction on grain sorghum hybrids in the pre- and post-flowering phases in the Brazilian semiarid. Twenty-five hybrids were evaluated under controlled irrigation conditions in Nova Porteirinha-MG and Teresina-PI. In the Nova Porteirinha, the hybrids were cultivated under conditions of non-drought stress and with drought stress in pre- and post-flowering stage. On the other hand, in Teresina, the experiment took place with non-drought stress and drought stress at post-flowering stage. The experimental design was in randomized complete blocks, in factorial scheme, with three replications. Drought stress reduced grain yield by more than 40%, showing that even being resistant, sorghum is affected by drought. Hybrids 1168093, 1167092, 1236020 and 1423007 showed high yields in the various environments, outyielding the commercial controls, what allows the recommendation of these cultivars for the semiarid areas or late off-season in the Cerrado region. Made available in DSpace on 2020-07-02T11:11:36Z (GMT). No. of bitstreams: 1 GrainSorghumGrownJAS2020.12.4.pdf: 690667 bytes, checksum: 2d7693f45b05bd7cdbc3614dbcda345f (MD5) Previous issue date: 2020

DETERMINAÇÃO DO COEFICIENTE DE CULTURA DO CAPIM-MOMBAÇA MANEJADO EM DIFERENTES ESTAÇÕES DO ANO NO SEMIÁRIDO MINEIRO VIRGÍLIO JAMIR GONÇALVES MOTA¹; ABNER JOSÉ DE CARVALHO2; FLÁVIO GONÇALVES OLIVEIRA3; VIRGÍLIO MESQUITA GOMES4; FLÁVIO PINTO MONÇÃO5 E VIRGÍLIO JAMIR GONÇALVES MOTA FILHO6 1 Eng. Agrônomo, Doutor, Prof. DCA/UNIMONTES, Campus Janaúba – MG. Av. Reinaldo Viana, 2630, Janaúba - MG, 39440-000, Brasil. e-mail: virgilio.mota@unimontes.br 2 Eng. Agrônomo, Doutor, Prof. DCA/UNIMONTES, Campus Janaúba – MG. Av. Reinaldo Viana, 2630, Janaúba - MG, 39440-000, Brasil. e-mail: abner.carvalho@unimontes.br 3 Eng. Agrícola, Doutor, Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais. ICA/UFMG, campus Montes Claros-MG, Brasil. flagiogoliveira@ibest.com.br 4 Eng. Agrônomo, Doutor, Prof. DCA/UNIMONTES, Campus Janaúba – MG. Av. Reinaldo Viana, 2630, Janaúba - MG, 39440-000, Brasil. e-mail: virgilio.gomes@unimontes.br 5 Zootecnista, Pós-Doutor, Prof. colaborador do PGZ/DCA/UNIMONTES, Campus Janaúba – MG. Av. Reinaldo Viana, 2630, Janaúba - MG, 39440-000, Brasil. e-mail: moncaomoncao@yahoo.com.br 6 Eng. Agrônomo, Mestre, Prof. DCA/UNIMONTES Campus Janaúba – MG. Av. Reinaldo Viana, 2630, Janaúba - MG, 39440-000, Brasil. e-mail: virgiliojamir@gmail.com 1 RESUMO Objetivou-se avaliar o coeficiente de cultura (kc), a produção de matéria seca (PMS) e a eficiência do uso da água do capim-mombaça (Panicum maximum Jacq. cv Mombaça) manejado em diferentes estações do ano. Foram avaliadas quatro fases de manejo (I, II, III e IV) caracterizadas por alturas para cortes das plantas baseadas na fenologia do capim-mombaça, correspondendo à primeira fase (45 a 56 cm – início da rebrotação) com base na interceptação luminosa de 95%, seguindo delineamento inteiramente casualizado, com cinco repetições. O capim foi manejado sob cortes em lisímetros de drenagem. Os cortes foram efetuados quando o capim atingia 90 cm de altura deixando resíduo de 45 cm. A PMS no verão, outono e inverno/primavera foi de 9.994, 8.261 e 10.705 kg.ha-1, respectivamente. O consumo de água no verão, outono e inverno/primavera foi de 697, 396 e 1711 mm, respectivamente, acarretando eficiência de seu uso de 14,28, 20,88 e 6,26 kg.ha-1.mm-1, respectivamente. O coeficiente de cultura do capim-mombaça variou de 0,79 a 1,25, nos períodos de verão e outono e de 0,62 a 1,06 no inverno/primavera. Palavras-chave: manejo da irrigação, evapotranspiração da cultura, pasto, estágios de desenvolvimento. MOTA, V. J. G.; CARVALHO, A. J.; OLIVEIRA, F. G.; GOMES, V. M.; MONÇÃO, F. P.; MOTA FILHO, V. J. G. DETERMINATION OF CULTURE COEFFICIENT OF MOMBASA GRASS MANAGED IN DIFFERENT SEASONS OF THE YEAR IN MINEIRO SEMIARID 2 ABSTRACT The objective of this study was to evaluate crop coefficient (kc), dry matter yield (PMS) and water use efficiency of mombaça grass (Panicum maximum Jacq. cv Mombasa) managed at different seasons of the year. Four management phases (I, II, III and IV) characterized by plant heights based on mombaça grass phenology corresponding to the first phase (45 to 56 cm - start of regrowth) based on light interception of 95% were evaluated, following a completely randomized design with five repetitions. The grass was managed under cuts in drainage lysimeters. The cuts were made when the grass reached 90 cm height leaving a residue of 45 cm. The PMS in summer, autumn and winter / spring was 9,994, 8,261 and 10,705 kg.ha-1, respectively. Water consumption in summer, autumn and winter / spring was 697, 396 and 1,711 mm, respectively, resulting in an efficiency of 14.28, 20.88 and 6.26 kg.ha-1.mm-1, respectively. The crop coefficient of mombaça grass ranged from 0.79 to 1.25 in summer and autumn and from 0.62 to 1.06 in winter/spring. Keywords: irrigation management, crop evapotranspiration, pasture, stages of development.

The objective of this study was to evaluate nutrient concentration and nutritional efficiency in ‘Gigante’ cactus pear under different chemical, organic and organomineral fertilizations, planting configurations and spacings, during three production cycles. Seventy two treatments, involving two types of configuration in the plots, three spacings in the subplots and 12 types of fertilization in the sub-subplots were arranged in a split-split-plot scheme, in a randomized block design, with three repetitions. At the time of harvest of each production cycle, 40 cladode tissue samples were collected per treatment to determine dry matter mass and nutrient concentration, which were used to calculate the coefficients of biological utilization of nutrients. Organic fertilization reduces Mn concentrations in cladodes to levels below the sufficiency range. The nutritional efficiency of N, S, P, Mn and Zn is higher with organic and organomineral fertilizations and are associated with higher dry matter yields, whereas K nutritional efficiency is higher with mineral fertilization. The absence of fertilization or application of 30 Mg ha-1 year-1 of bovine manure is insufficient to ensure nutritional status and dry matter yield above 15 Mg ha-1 in ‘Gigante’ cactus pear. RESUMO Objetivou-se com o presente trabalho avaliar durante três ciclos de produção, os teores de nutrientes e a eficiência nutricional em Palma forrageira ‘Gigante’ submetida a diferentes adubações química, orgânica e organomineral, configurações de plantio e espaçamentos. Setenta e dois tratamentos, envolvendo dois tipos de arranjos nas parcelas, três espaçamentos nas subparcelas e 12 tipos de adubação nas sub-subparcelas foram dispostos em esquema de parcelas sub-subdivididas, em delineamento experimental em blocos casualizados, com três repetições. Na época da colheita de cada ciclo produtivo, coletaram-se 40 amostras de tecidos dos cladódios por tratamento para determinação da massa de matéria seca e dos teores de nutrientes e a partir destes calcularam-se os coeficientes de utilização biológica dos nutrientes. Verificou-se que a adubação orgânica diminui os teores de Mn nos cladódios abaixo da faixa de suficiência. A eficiência nutricional de N, P, S, Mn e Zn é maior com adubação orgânica e organomineral e estão associadas às maiores produtividades de matéria seca, enquanto de K é maior com adubação mineral. A ausência de adubação ou aplicação de 30 Mg ha-1 ano-1 de esterco bovino é insuficiente para assegurar o estado nutricional e produtividade de matéria seca acima de 15 Mg ha-1 em palma forrageira ‘Gigante’.

The technological quality from grains of bean should be evaluated in trials of elite lines to complement the agronomic performance evaluation, ensure the selection and recommendation of new cultivars, and guarantee its greater acceptance by the consumer market. Thus, this study aimed to evaluate the technological quality from selected genotypes of black bean grains. We used 12 elite lines and 4 cultivars from commercial black group constituents of the Value for Cultivation and Use (VCU). The trial was carried out on the Experimental Farm of Federal University of Vicosa-MG, in Coimbra County, in the 2012 crops of autumn/winter seasons. The experimental design was in randomized block, with three replications. The evaluated characteristics were shape, degree of flattening, thousand grains weight, hard-to-cook grains percentage, cooking time, husk percentage and the hydration capacity of the grains. The lines VP 24, VP 25 and VP 29 present the medium level of resistance to cooking similar to the cultivars (controls), and the other evaluated lines have normal resistance to bean cooking. The genotypes CNFP 11977, VP 29 and ‘Ouro Negro’ attain, in shorter time, 50% of the maximum hydration capacity of the grains, and resistance between normal and medium for cooking time. The lines VP 29 and CNFP 11977 also obtained the greatest hydration capacity for most evaluated times. The lines VP 26, VP 29, CNFP 11992, VP 27, VP 28, and CNFP 11977 present the best characteristics associated with technological quality of grains.

Cactus pear is adapted to semi-arid conditions. In this study, the objective was to evaluate the water use efficiency and green and dry mass yields of the cultivar Gigante under different fertilization rates and sources in three production cycles, spacing and planting arrangement. Seventy two treatments, involving two types of arrangements in the plots, three spacings in the subplots and 12 types of fertilization in the sub-subplots were arranged in a split-split-plot scheme, using randomized block design with three repetions. Dry mass content decreases while water use efficiency and green mass and dry mass yields increase from the first to the third cycle. It is feasible to use planting arrangements in triple or quadrupling rows which allow increasing the mechanization index of the crop. Organomineral fertilization with 30 or 60 Mg ha-1 year-1 of bovine manure combined with 150-300-600 kg ha-1 year-1 of N-P2O5-K2O and 300-300 kg ha-1 year-1 of P2O5-K2O, respectively; organic fertilization with 90 Mg ha-1 year-1 of manure; and mineral fertilization with 300-300-600 kg ha-1 year-1 of N-P2O5-K2O ensure green mass and dry mass yields greater than 200 and 15 Mg ha-1 cycle-1, respectively, and water use efficiency greater than 20 kg ha-1 mm-1 in ‘Gigante’ cactus pear. It is concluded that yields of this magnitude are ensured with application of about 300-300-300 kg ha-1 year-1 of N-P2O5-K2O using organic, organomineral or mineral sources. RESUMO A palma forrageira é adaptada às condições semiáridas. Neste trabalho, objetivou-se avaliar em três ciclos de produção, a eficiência do uso da água e as produtividades de massa verde e matéria seca, da cultivar Gigante sob diferentes doses e fontes de adubação, espaçamento e arranjos de plantas. Setenta e dois tratamentos, envolvendo dois arranjos nas parcelas, três espaçamentos nas subparcelas e 12 tipos de adubação nas sub-subparcelas foram dispostos em esquema de parcelas sub-subdivididas, em delineamento em blocos casualizados, com três repetições. O teor de matéria seca decresce e a eficiência do uso da água e as produtividades de massa verde e matéria seca aumentam do primeiro para o terceiro ciclo. É viável o uso de configurações de plantio em fileiras triplas ou quádruplas que possibilitam aumentar o índice de mecanização na cultura. As adubações organominerais com 30 ou 60 Mg ha-1 ano-1 de esterco bovino combinadas com 150-300-600 kg ha-1 ano-1 de N-P2O5-K2O e 300-300 kg ha-1 ano-1 de P2O5-K2O, respectivamente, adubação orgânica com 90 Mg ha-1 ano-1 de esterco bovino e adubação mineral com 300-300-600 kg ha-1 ano-1 de N-P2O5-K2O proporcionam produtividades de massa verde e de matéria seca maiores que 200 e 15 Mg ha-1 ciclo-1, respectivamente, e eficiência de uso da água maior que 20 kg ha-1 mm-1 em palma forrageira ‘Gigante’. Conclui-se que produtividades dessa ordem são asseguradas com aplicação de cerca de 300-300-300 kg ha-1 ano-1 de N-P2O5-K2O com fontes orgânica, organomineral ou mineral.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Outra Agência The definition of experimental plot size is an essential tool to ensure precision in statistical analysis in experiments. The objective of this study was to estimate the plot size for the cactus pear cv. Gigante using the Modified Maximum Curvature Method, under the semi-arid conditions of Northeastern Brazil. The uniformity test was conducted at the Federal Institute of Bahia, Guanambi Campus, Bahia state, Brazil, during the agricultural period from 2009 to 2011. The spatial arrangement was composed of ten rows with 50 plants each, whose evaluated area was formed by the eight central rows with 48 plants per row, making 384 plants and area of ​​153.60 m2. The following variables were evaluated: plant height; length, width and thickness of cladode; number of cladodes; total area of cladodes; cladode area and green mass yield in the third production cycle. In the evaluations, each plant was considered as a basic experimental unit (BEU), with an area of ​​0.4 m2, comprising 384 basic units (BU), whose adjacent ones were combined to form 15 pre-established plot sizes with rectangular shapes and in rows. The characteristics total area of cladodes and green mass yield require larger plot sizes to be evaluated with greater experimental accuracy. For experimental evaluation of cactus pear cv. Gigante, plot size should be eight plants in the direction of the crop row. A definição do tamanho da parcela experimental configura-se como ferramenta essencial para assegurar a precisão na análise estatística em experimentos. Assim objetivou-se estimar o tamanho de parcela para a cultura da palma forrageira cv. Gigante por meio do Método da Máxima Curvatura Modificado, nas condições do Semiárido Nordestino. O ensaio de uniformidade foi conduzido no Instituto Federal Baiano, Campus Guanambi, Bahia, Brasil, no período agrícola de 2009 a 2011. O arranjo espacial foi composto por dez fileiras com 50 plantas cada, cuja área útil foi formada pelas oito fileiras centrais com 48 plantas por fileira, perfazendo 384 plantas e área de 153,60 m². Foram avaliadas as variáveis altura da planta; comprimento, largura e espessura do cladódio; número de cladódios; área total do cladódio; área do cladódio e a produtividade de massa verde no terceiro ciclo de produção. Nas avaliações, cada planta foi considerada como uma unidade experimental básica (UEB), com área de 0,4 m², contemplando 384 unidades básicas (UB), cujas adjacentes foram combinadas de modo a formar 15 tamanhos de parcelas pré-estabelecidos com formatos retangulares e em fileiras. As características área total do cladódio e produtividade de massa verde exigem maiores tamanhos de parcela para serem avaliadas com maior precisão experimental. Para avaliação experimental da palma forrageira cv. Gigante, o tamanho de parcela deve ser de oito plantas no sentido da fileira de cultivo.

Weed interference is one of the main limiting factors in the cowpea yield. In this sense, we aimed to determine the periods of weed interference in the cowpea crop in the semi-arid region of Minas Gerais. The treatments were arranged in a 2 x 10 factorial scheme, with two factors: coexistence and control of weed and ten periods: 0, 7, 14, 21, 28, 35, 42, 49, 56 and 63 days after emergence (DAE) subjected to control and coexistence. The evaluated characteristics were dry weight of weeds and the cowpea, weight of 100 grains and yield, which was fitted to the exponential model and the periods of interference of the weed community were determined. The period before interference (PBI) occurred up to 20 DAE, with weed control having to be performed up to 32 DAE. The critical period for weed control (CPWC) was from 21 to 32 days after emergence of the crop. The cowpea bean yield reduced 73.5% with the weed interactions during the whole cycle, under conditions of the semi-arid of Minas Gerais. Made available in DSpace on 2020-06-05T11:05:37Z (GMT). No. of bitstreams: 1 Periods-weed.pdf: 1926972 bytes, checksum: d975ce9910188da8f8d233f29de6dbcc (MD5) Previous issue date: 2020

The understanding of plant behavior and its reflexes on yield is essential for rural planning; thus, the biomathematical models are promising in the yield prediction of cactus pear cv. Gigante. This study aimed to adjust, through simple and multiple regression analysis, models for predicting the yield of cactus pear cv. Gigante. The study, using homogeneous treatments, was developed at the Instituto Federal Baiano, Campus of Guanambi, Bahia, Brazil. Data were collected in an area consisting of 384 basic units (plants), in which the yield, defined as a dependent variable, and the predictor variables: plant height (PH), cladode length (CL), cladode width (CW), and cladode thickness (CT), number of cladodes (NC), cladode area (CA), and total cladode area (TCA) were evaluated. Simple linear regression models, multiple regression models only with simple effects for the explanatory variables, and the multiple regression models considering the simple and quadratic effects, and all its possible interactions were adjusted. From this last model, a reduced model was obtained by discarding the less relevant effects, using the Stepwise methodology. The use of the vegetative traits, TCA, NC, CA, CL, CT, and CW, through the adoption of multiple linear regression, quadratic interaction or just the variable TCA by the use of simple linear regression, allows the yield prediction of cactus pear, with adjusted R² of 0.82, 0.76, and 0.74, respectively.

Minimum limits of soil water storage should be established for the irrigation management of crops, in order to satisfactorily provide water to plants. This study aimed to define the soil water availability factor (f factor) that provides the maximum agronomic yield and maximum water-use efficiency for drip-irrigated common bean cultivars. The experiment was carried out in a randomized block design, with four replications. The treatments were arranged in split plots, with the plots consisting of f factors (0.20, 0.35, 0.50, 0.65 and 0.80) and subplots consisting of common bean cultivars (BRS Pérola and BRS Estilo). The use of f factors between 0.30 and 0.35 is recommended for common bean crops to obtain the maximum agronomic yield and maximum water-use efficiency. The BRS Estilo cultivar presents a water-use efficiency 16 % higher than the BRS Pérola.

The objective of the study with ‘Gigante’ cactus pear was to determine the size of plots that optimize the implementation of experiments with greater accuracy, spatial adequacy and efficiency of use of the experimental area by the Hatheway method (1961). The experiment was conducted in a uniform spacing of 2.0 x 0.2 m with 384 basic experimental units (BEUs). The vegetative descriptors were evaluated in the third production cycle. The coefficient of experimental variation (CVe) is the factor with the greatest influence for the experimental plot design; followed by the parameters - index d, which determines the difference to be detected between treatments; by the number of replications and, finally, by the number of treatments, which has the smallest effect on the plot size (BEUs). For the efficiency of use of the experimental area - EUEA, one can select larger plots (three BEU) with a lower number of repetitions (three) or smaller plots (two UEB) with a higher number of repetitions (10) with the same level of accuracy to evaluate the yield of ‘Gigante’ cactus pear. However, the selection criteria are based on the smallest experimental area, reflecting the maximum of EUEA. Useful plots with eight basic units are considered efficient for experiments with cactus pear.

The objective of this work was to evaluate the agronomic performance of elite-strains of cowpea cultivars under the conditions of the north of Minas Gerais (MG), Brazil. Fifteen elite-strains and five erect and semi-erect cultivars of cowpea were evaluated in the 2014 and 2015 summer-fall crop seasons in Janaúba MG. A randomized block experimental design was used with four replications. Plant size, lodging and value of cultivation, pod length and grain yield were evaluated. The data of the two crops were subjected to individual and joint analysis of variance. The genotype-crop interactions significantly affected all studied variables. The strains MNC04-792F-146 and MNC04-792F-144 stood out as the most productive genotypes in both crops. The cultivars BRS Itaim and BRS Novaera presented adequate size and lodging characteristics for cultivation, and values of cultivation that meet commercial standards, thus representing good alternatives for the genotypes cultivated in the north of Minas Gerais. RESUMO Objetivou-se com este trabalho avaliar a performance agronômica de linhagens-elite e cultivares de feijão-caupi, nas condições de cultivo do Norte de Minas Gerais. Foram avaliadas 15 linhagens-elite e cinco cultivares de feijão-caupi de portes ereto e semiereto, nas safras de verão-outono de 2014 e 2015, em Janaúba, MG. O delineamento experimental foi o de blocos casualizados, com quatro repetições. Foram avaliados o porte da planta, o grau de acamamento e o valor de cultivo, o comprimento da vagem e o rendimento de grãos. Os dados obtidos foram submetidos a análises de variância individuais e conjunta, envolvendo as duas safras de cultivo. Verificou-se efeito significativo para a interação entre genótipos e safras para todas as variáveis estudadas. As linhagens MNC04-792F-146 e MNC04-792F-144 destacaram-se por estarem entre os genótipos mais produtivos nas duas safras avaliadas. As cultivares BRS Itaim e BRS Novaera apresentaram simultaneamente características de porte e acamamento adequadas para o cultivo, além de obterem valor de cultivo compatível com o padrão comercial, representando boas alternativas de cultivo no Norte de Minas Gerais.

The objective was to identify the species and quantify the importance value index of weeds in the cultivation of arabica coffee in two irrigation systems, at different times of the year, in the northern region of Minas Gerais. A phytosociological survey was carried out in each season of the year (spring, summer, autumn and winter) in an area cultivated with the species Coffea arabica, subjected to two irrigation systems (sprinkling and dripping). The coffee crop was implanted at a spacing of 3.5 m between rows and 0.7 meters between plants. The collection of weeds was performed using the standard method of the square inventory, which was launched between the lines of the crop. The identification of the species was carried out, the number of individuals was quantified, the dry mass, frequency, density, abundance, importance value index and coverage, and the similarity index. 33 weed species were identified, being the species with the highest IVI Euphorbia hirta, Brachiaria plantaginea, Digitaria horizontalis, Cyperus rotundus and Amaranthus spp. It was observed a higher occurrence of weeds from the monocot group in the sprinkler irrigation system while in the drip there were predominance of dicot plants.

Selection of tolerant plants is essential to meet the challenges of food production. The objective of this study was to evaluate agronomic and physiological characteristics as indicators for the selection of water restriction-tolerant grain sorghum genotypes. The experiments were conducted in 2014, 2015 and 2016. Two trials were installed in each year, one subjected to full irrigation and the other to water restriction. In the first one, irrigation was performed periodically, at a 2-day interval, to maintain soil moisture close to field capacity. In the second one, irrigation was suspended in the pre-flowering period, keeping the restriction for 30 days. Four sorghum genotypes were used: 9503062 and 9618158 - drought sensitive (S); 9910032 and P898012 - drought tolerant (T). The experimental design was randomized blocks with four replicates. Stomatal conductance, relative chlorophyll content, photosynthetically active leaf area, plant height and yield were evaluated. Joint analysis of the experiments subjected to full irrigation and water restriction of the three years was performed. Under water restriction it was not possible to distinguish between sensitive and tolerant materials. The characteristics evaluated in this experiment did not allow a conclusive distinction between tolerant and sensitive genotypes.

Drought stress is a serious obstacle for crop production, especially in arid and semi-arid areas of the world. Sorghum is a useful crop to grow in areas with erratic, poorly distributed or inadequate rainfall. To help determine the best alternatives, we evaluated 30 sorghum cultivars with and without water stress in the post-flowering plant stage. The work was carried out at the Experimental Station of Gorutuba, in Nova Porteirinha, MG, Brazil, during 2013 and 2014 seasons. The experimental design was a randomized complete block, with three replications and two water regimes. The traits evaluated were grain yield, number of days to flowering, plant height and 1,000 grain mass. Water restriction reduced the grain yield by 68.9% in 2013, 31.2% in 2014 and 50.1% in the average of the two years. The genotypes with best grain yield stability were B.Tx635, SC 720 and BR012RxSC566. Water stress significantly reduced plant height and grain mass.

Appropriate plot size is recognized as a means of maximizing experimental accuracy and contributes to efficient treatment assessment. This study aimed to estimate the optimal plot size for experiments with ‘Gigante’ cactus pears using the comparison of variances method (CVM). A uniformity trial was conducted to assess plant height (PH), number of cladodes (NC), yield (Y), cladode area index (CAI), cladode length (CL), width (CW), thickness (CT) and cladode area (CA) in a cactus pear crop. A rectangular-shaped plot consisting of 10 rows of 50 plants each was used, totaling 500 plants, with 384 basic units (BU), corresponding to the study area. A hierarchical classification approach was adopted, simulating a split-plot design in which each plant was denominated a basic unit (BU), and considering the effects of blocks (B), plots (P)/B, subplots (S)/P/B, rows (R)/S/P/B and plants (Pln)/F/S/P/B. This resulted in five plots sizes, consisting of 1, 12, 24, 48 and 96 basic units. Plots with 12, 24, 48 and 96 BU were statistically equal for the variables Y, PH, NC, CAI, CL, CW and CT, with lower variances than the plot with 1 BU. As such, 4.8 m² with 12 basic units is the optimal experimental plot size for ‘Gigante’ cactus pears.

RESUMO - Objetivou-se com o trabalho determinar o período anterior à interferência (PAI), período total de prevenção à interferência (PTPI) e período crítico de prevenção à interferência (PCPI) das plantas daninhas na cultura do sorgo sacarino, cultivar BRS 506. O trabalho foi conduzido na Fazenda Experimental da Embrapa Milho e Sorgo, em Nova Porteirinha, MG. Os tratamentos foram constituídos pela combinação de dois espaçamentos entre linhas do sorgo (0,50 e 0,70 m) e dez períodos de controle ou de convivência das plantas daninhas com a cultura (0, 7, 14, 21, 28, 35, 42, 49, 56 e 120 dias após a emergência). O PAI foi de 19 e 24 DAE para o espaçamento 0,5 m e 0,7 m, respectivamente. O PTPI para produtividade de massa verde total foi 17 e 10 DAE para os espaçamentos de 0,5 m e 0,7 m, respectivamente. Não houve PTPI para os demais parâmetros. Não houve PCPI para nenhum dos parâmetros avaliados (PAI > PTPI).Palavras-chave: Sorghum bicolor, competição, períodos de interferência, BRS 506, PAI, PTPI.WEED INTERFERENCE IN SWEET SORGHUM SOWED IN DIFFERENT SPACINGS IN MINAS GERAIS SEMI-ARID CONDITIONSABSTRACT - The objectives of this work were to determine the period before weed interference (PBWI), the total period of weed interference (TPWI) and the critical period of weed interference (CPWI) for the BRS 506 sweet sorghum cultivar. The experiment was conducted at the experimental farm of Embrapa Milho e Sorgo at Nova Porteirinha, MG. The treatments were a combination of two sorghum row spacings (0.50 and 0.70 m) and ten periods of weeds coexisting with the crop ( 0, 7, 14, 21, 28, 35, 42, 49, 56 and 120 days after emergence, DAE). The PBWI was 19 and 24 DAE for 0.5 m and 0.7 m spacings, respectively. The TPWI for total green mass productivity was 17 and 10 DAE for 0.5 m and 0.7 m spacings, respectively. There was no TPWI for the other parameters. There was no CPWI for any of the evaluated parameters (PBWI > TPWI).Keywords: Sorghum bicolor, competition, interference periods, BRS 506, PBWI, TPWI.

Behavior analysis and plant expression are the answers the researcher needs to construct predictive models that minimize the effects of the uncertainties of field production. The objective of this study was to compare the simple and multiple linear regression methods and the artificial neural networks to allow the maximum security in the prediction of harvest in ‘Gigante’ cactus pear. The uniformity test was conducted at the Federal Institute of Bahia, Campus Guanambi, Bahia, Brazil, coordinates 14°13′30″ S, 42°46′53″ W and altitude of 525 m. At 930 days after planting, we evaluated 384 basic units, in which were measured the following variables: plant height (PH); cladode length (CL), width (CW) and thickness (CT); cladode number (CN); total cladode area (TCA); cladode area (CA) and cladode yield (Y). For the comparison between the artificial neural networks (ANN) and regression models (single and multiple-SLR and MLR), we considered the mean prediction error (MPE), the mean quadratic error (MQE), the mean square of deviation (MSD) and the coefficient of determination (R2).The values estimated by the ANN 7-5-1 showed the best proximity to the data obtained in field conditions, followed by ANN 6-2-1, MLR (TCA and CT), SLR (TCA) and SLR (CN). In this way, the ANN models with the topologies 7-2-1 and 6-2-1, MLR with the variables total cladode area and cladode thickness and SLR with the isolated descriptors total cladode area and cladode number, explain 85.1; 81.5; 76.3; 74.09 and 65.87%, respectively, of the yield variation. The ANNs were more efficient at predicting the yield of the ‘Gigante’ cactus pear when compared to the simple and multiple linear regression models.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Outra Agência The optimum plot size for ‘Gigante’ cactus pear can be estimated by several methods; thus, ultimately aiming for efficiency, simple use and high precision, the objective of this study was to compare methods for estimating plot sizes: modified maximum curvature method, Hatheway’s convenient plot size method, linear and quadratic response plateau models, and comparison of variances method for evaluating phenotypic characteristics in experiments with ‘Gigante’ cactus pear. Plot sizes were estimated by conducting a uniformity trial. Estimated optimum plot sizes varied with the method and vegetative characteristic. The quadratic response plateau regression estimated the largest plot sizes, whereas Hatheway’s method estimated the smallest plot sizes. Comparison of variances method estimated intermediate plot sizes in comparison with the other methods for most measured characteristics. Plots sizes estimated by modified maximum curvature method are more consistent with results reported by studies on ‘Gigante’ cactus pear. 10 basic unit plot sizes estimated by the linear response plateau model can be used with high precision and practical feasibility for growing cactus pear, thereby improving the use of resources. O tamanho ótimo de parcela para palma forrageira ‘Gigante’ pode ser estimado por vários métodos; assim, visando em última análise a eficiência, uso simples e alta precisão, o objetivo deste estudo foi comparar métodos para estimar tamanhos de parcelas: método de curvatura máxima modificada, método de tamanho de parcela conveniente de Hatheway, modelos de platô de resposta linear e quadrática e método de comparação de variâncias para avaliação de características fenotípicas em experimentos com palma forrageira 'Gigante'. Os tamanhos das parcelas foram estimados através da realização de um ensaio de uniformidade. Os tamanhos ótimos estimados de parcela variaram com o método e a característica vegetativa. A regressão de platô de resposta quadrática estimou os maiores tamanhos de parcelas, enquanto o método de Hatheway estimou os menores tamanhos de parcelas. O método de comparação de variâncias estimou tamanhos de parcelas intermediários em comparação com os outros métodos para a maioria das características medidas. Os tamanhos de parcelas estimados pelo método da curvatura máxima modificada são mais consistentes com os resultados relatados por estudos sobre a palma forrageira ‘Gigante’. 10 tamanhos de parcelas de unidades básicas estimados pelo modelo de platô de resposta linear podem ser usados ​​com alta precisão e viabilidade prática para o cultivo de palma forrageira, melhorando assim o uso dos recursos.

O objetivo do presente trabalho foi selecionar linhagens de sorgo mais tolerantes a seca e responsivas a melhoria do ambiente. Os tratamentos foram arranjados em um esquema fatorial, composto por 25 linhagens e dois regimes hidricos. Os experimentos foram realizados em tres anos consecutivos (2006, 2007 e 2008), totalizando seis experimentos. O delineamento utilizado foi o de blocos casualizados, com tres repeticoes. Para selecao dos genotipos foram estimados parâmetros de adaptabilidade e estabilidade para produtividade de graos utilizando os metodos univariados de Lin & Bins e Annicchiarico, e analise multivariada AMMI. A selecao para adaptabilidade geral pelos dois primeiros metodos e bastante similar, diferindo, no entanto do terceiro metodo. A produtividade media das linhagens no ambiente com estresse foi 39% menor quando comparado ao ambiente sem estresse hidrico. Foram detectadas diferencas significativas para as interacoes linhagens (L) x anos (A), linhagens (L) x regime hidrico (R) e LxAxR, indicando a complexidade de se trabalhar com selecao para tolerância a seca em sorgo em nivel de campo. Os metodos univariados complementaram o metodo AMMI, possibilitando a selecao de linhagens tolerantes, estaveis e responsivas ao ambiente. As linhagens mais tolerantes e estaveis foram 9929020, CMSXS 230B e N 95B, seguidas pelas linhagens BR 008B, Tx 2737 e Tx 2908, de produtividades elevadas, mas de estabilidades intermediarias.

The objective of this study was to estimate the adaptability and stability of grain sorghum hybrids grown under post-flowering water stress and non-stress conditions. The trials were carried out in Nova Porteirinha-MG during the season of 2014 and 2015, and in Teresina-PI in the 2014 season. Twenty-nine-grain sorghum hybrids were evaluated, in a randomized complete block design, with three replications. Plots consisted of four lines with 3 m long. The grain yield data were submitted to the individual variance analysis, having considered the effects of the hybrids as fixed and the other effects as random. The joint analysis was carried out, and when the interaction genotypes x environments was significant, the grain yield data were submitted to the adaptability and stability analysis by the GGE biplot method. A substantial reduction in the grain yield in environments with water stress was found. The highest yielding hybrids under water stress conditions in Nova Porteirinha-MG were 50A50, AG1080, AG1090, DKB550, DKB590, Jade, and BM737, and the highest yielding hybrids under the water stress in Teresina-PI were 1G282, 1G244, and A9721R. Considering all environments, the highest yielding hybrids were 1G282, DKB540, A9721R, 1G100, and AG1090. Made available in DSpace on 2017-09-23T00:13:45Z (GMT). No. of bitstreams: 1 Performancegrain.pdf: 1041239 bytes, checksum: 8ccfa98437ab622e9f993a05fe203971 (MD5) Previous issue date: 2017-09-21

The goal of this study is to characterize the weed phytosociology in some major erect and prostrate cowpea cultivars in Brazil, in the Northern growing conditions of Minas Gerais state. The test was conducted in Janaúba, Minas Gerais state. The treatments consisted in five erect cultivars (BRS Guariba, BRS Tumucumaque, BRS Novaera, BRS Itaim and BRS Cauamé) and four prostrate ones (BRS Marataoã, BRS Pajeú, BRS Pujante and BRS Xiquexique). The plots were composed of four five meter rows, spaced 0.5 m apart, for erect cultivars and 1.0 m for the prostrated ones. Weed sampling was performed 50 days after sowing by standard Square Method. The species were identified and quantified, and then dried at 65 oC for 72 hours and weighed. The frequency, absolute and relative density and abundance, the importance value index (IVI) and the similarity index were evaluated. In the erect cultivars, the Amaranthaceae, Euphorbiaceae, Asteraceae and Convolvulaceae families stood out with higher IVI’s. In prostrate cultivars, the Amaranthaceae, Asteraceae and Malvaceae families stood out. Portulaca oleracea and Amaranthus spp. were the species with the highest IVI. The similarity index between erect and prostrate cultivars was 72%; nine of the 16 families occurred in both cultivars. BRS Tumucumaque, erect, and BRS Pujante, prostrate had lower weed infestation. RESUMO Objetivou-se com este trabalho caracterizar a fitossociologia de plantas daninhas em alguns das principais cultivares de feijão-caupi do Brasil, de porte ereto e prostrado, nas condições de cultivo do Norte de Minas Gerais. O ensaio foi conduzido em Janaúba, MG. Os tratamentos consistiram de cinco cultivares de porte ereto (BRS Guariba, BRS Tumucumaque, BRS Novaera, BRS Itaim e BRS Cauamé) e quatro de porte prostrado (BRS Marataoã, BRS Pajeú, BRS Pujante e BRS Xiquexique). As parcelas foram compostas por quatro fileiras de cinco metros, espaçadas de 0,5 m entre si, para os cultivares de porte ereto, e de 1,0 m, para os cultivares de porte prostrado. A amostragem das plantas daninhas foi realizada aos 50 dias após a semeadura, pelo método-padrão do quadrado inventário. As espécies foram identificadas e quantificadas e, em seguida, secas em estufa a 65 ºC por 72 horas e pesadas. Avaliaram-se as frequências, densidades e abundâncias, absolutas e relativas, o índice de valor de importância (IVI) e o índice de similaridade. Nos cultivares de porte ereto, destacaram-se as famílias Amaranthaceae, Euphorbiaceae, Asteraceae e Convolvulaceae com maiores IVI. Nos cultivares de porte prostrado, destacaram-se as famílias Amaranthaceae, Asteraceae e Malvaceae. Portulaca oleracea e Amaranthus spp. foram as espécies com maior IVI. O índice de similaridade entre os cultivares de porte ereto e prostrado foi de 72%, sendo que nove das 16 famílias ocorreram em cultivares dos dois portes. Os cultivares BRS Tumucumaque, de porte ereto, e BRS Pujante, de porte prostrado, apresentaram menor infestação de plantas daninhas.

The objective of this paper was to characterize the phytosociology of weeds in function of different types of growth of common bean cultivars in the North of Minas Gerais. The study was conducted in the experimental area, located in the municipality of Janaúba, MG. The treatments consisted of eight commercial cultivars of common beans with different types of growth. The design was done in randomized blocks, with three replications. The soil preparation was conventional and the planting was done in June, with manual seeders, with a 0.5 m spacing between rows. The phytosociological survey was performed in two phases of bean cultivation, in stages V3 and R8. The method used was the square inventory one, with a 0.25 m2 frame, randomly released once in each plot. Samples of each square were identified and quantified by family, genus and species, and the sampled plants were collected with their complete structure. Next, the material was sent to a drying greenhouse with forced air circulation at 65 oC for 72 hours, for drying and determination of weight of dry matter. We also estimated the Relative Frequency, Relative Density and Relative Abundance to determine the importance value index and similarity index. At the V3 stage, the species Sorghum halepense, Brachiaria plantaginea and Boerhavia diffusa had higher importance value indexes. At the R8 stage, the Amaranthus viridis specie showed higher importance value index and dry matter. In more prostrate cultivars, the weeds present lower importance value indexes at the R8 stage. RESUMO Objetivou-se com este trabalho caracterizar a fitossociologia de plantas daninhas em função de diferentes tipos de crescimento de cultivares de feijão-comum, no norte de Minas Gerais. O trabalho foi realizado em área experimental, localizada no município de Janaúba, MG. Os tratamentos consistiram de oito cultivares comerciais de feijão-comum de diferentes tipos de crescimento. O delineamento foi em blocos casualizados com três repetições. O preparo do solo foi convencional, e o plantio, realizado no mês de junho, com semeadoras manuais, no espaçamento de 0,5 m entre linhas. Realizou-se o levantamento fitossociológico em duas fases de cultivo do feijoeiro, nos estádios V3 e R8. Utilizou-se o método do quadrado inventário, com quadro de 0,25 m2, lançado aleatoriamente uma vez em cada parcela. As amostras de cada quadrado foram identificadas e quantificadas por família, gênero e espécie, sendo as plantas amostradas coletadas com estrutura completa. Em seguida, o material foi encaminhado para estufa de secagem com circulação forçada de ar a 65 ºC por 72 horas, para secagem e determinação da massa da matéria seca. Foram também estimadas a frequência relativa, densidade relativa e abundância relativa, para determinação do índice de valor de importância e índice de similaridade. No estádio V3, as espécies Sorghum halepense, Brachiaria plantaginea e Boerhavia diffusa apresentaram maiores índices de valor de importância. No estádio R8, Amaranthus viridis mostrou maior índice de valor de importância e massa seca. Nos cultivares de crescimento mais prostrado, as plantas daninhas apresentaram menores índices de valor de importância no estádio R8.

O aumento de produtividade é o principal objetivo dos programas de melhoramento de feijão-comum. Contudo, algumas características relacionadas à qualidade tecnológica devem ser analisadas para assegurar que a recomendação de novas cultivares considere também aspectos comerciais importantes para a aceitação do consumidor. Assim, o objetivo deste trabalho foi avaliar a qualidade tecnológica de grãos de genótipos de feijão-comum do grupo comercial carioca. Foram utilizados grãos de 25 genótipos selecionados pelo convênio Estadual de pesquisa em melhoramento de feijão-comum (EMBRAPA, UFLA, UFV e EPAMIG) para compor o ensaio de VCU do grupo comercial carioca, sendo 21 novas linhagens e 4 cultivares comerciais usadas como testemunha. O delineamento experimental utilizado foi o de blocos casualizados, com três repetições. As características avaliadas foram à forma e o grau de achatamento dos grãos, a massa de mil grãos, a porcentagem de grãos duros, o teor de sólidos solúveis, o tempo de cocção, a porcentagem de casca e a capacidade de hidratação. Os resultados obtidos permitiram concluir que os genótipos que apresentam forma e grau de achatamento de acordo com o padrão comercial são EMB14, CNFC 10432, CNFC 10408, EMB4, P-18163, Pérola e BRSMG Madrepérola. Os genótipos MAIV-18259, VC-20, VC-23, RCII-219, CVIII-2, EMB4, MAIV-15204, CVIII-5, e BRSMG Majestoso apresentam massa de mil grãos compatível com o padrão comercial para grãos do tipo carioca, que é no mínimo 23 g por cem grãos. A maioria dos genótipos avaliados não apresenta grãos duros. As linhagens CNFC 10408, MAIV-18259 e P-18163 apresentam os maiores teores de sólidos solúveis. Vinte dos genótipos avaliados apresentam tempo de cocção inferior ao exigido como padrão comercial, sendo que as linhagens EMB 9, EMB 4, MAIV-18524, CNFC 11965, VC-17 e CNFC 10432 são as que apresentam menores tempos de cozimento. As linhagens CNFC 11965, EMB4, EMB14 e CNFC 10432 despendem menor tempo para hidratação dos grãos. Palavras-chave: Cocção. Embebição. Ensaio de VCU. Phaseolus vulgaris L. Common bean variety improvement programs focus on productivity increase as their main goal. However, some characteristics related to technological quality must also be analyzed in order to assure that new recommended cultivars satisfy key commercial standards, related to consumer acceptance. This study evaluated the technological quality of seeds from different ‘carioca’ bean genotypes. We tested seeds from 25 bean genotypes, selected by the State Consortium for Research on Common Bean Improvement (including EMBRAPA, UFLA, UFV and EPAMIG) for the VCU assay of the carioca variety, including 21 new lines and 4 commercial cultivars, used as controls. The experiment was arranged in a randomized complete block design with three replications. We assessed the following traits: seed shape, seed constriction, 1000-seed weight, percentage of hard seeds, soluble solids content, cooking time, seed coat percentage, and hydration capacity. According to our results, the cultivars that met the commercial standards for seed shape and constriction were EMB14, CNFC 10432, CNFC 10408, EMB4, P-18163, Pérola and BRSMG Madrepérola. Genotypes MAIV-18259, VC-20, VC-23, RCII-219, CVIII-2, EMB4, MAIV-15204, CVIII-5, and BRSMG Majestoso had 1000-seed weight within carioca bean commercial standards (a minimum of 23g per 100 seeds). Most genotypes had no hard seeds. Lines CNFC 10408, MAIV-18259 and P-18163 had the highest soluble solids content. Twenty genotypes had cooking times below the maximum required by commercial standard, with lines EMB9, EMB4, MAIV-18524, CNFC 11965, VC-17, and CNFC 10432 having the shortest cooking time. Lines CNFC 11965, EMB4, EMB14, and CNFC 10432 also had the shortest time to soaking.

Para avaliar o efeito de doses de fluazifop-p-butil no desempenho do feijoeiro consorciado com braquiária, foi conduzido um experimento em Coimbra, MG, nas safras da seca de 2007 e das águas de 2007-2008. Foi utilizado o delineamento em blocos casualizados, com quatro repetições. Os tratamentos foram dispostos em esquema fatorial, envolvendo duas espécies de braquiária (Brachiaria brizantha e B. decumbens), seis doses de fluazifop-pbutil (0; 7,81; 15,62; 31,25; 62,50; e 125,00 g ha-1), mais o monocultivo de ambas as culturas. O feijoeiro foi plantado a 0,5 m entre linhas, com as sementes de braquiária sendo semeadas nas mesmas fileiras do feijão. Nos sistemas consorciados, além das doses de fluazifop-pbutil, utilizou-se fomesafen (125 g ha-1) e bentazon (336 g ha-1). Para o feijão solteiro foi utilizada uma mistura dos herbicidas fomesafen (125 g ha-1) e fluazifop-p-butil (100 g ha-1). Foram avaliados o estande final de plantas e o rendimento de grãos do feijoeiro com seus componentes primários. Os dados foram submetidos à analise de variância, sendo os efeitos das espécies de braquiária e das safras estudados pelo teste F, e os efeitos das doses de fluazifop-p-butil, por análise de regressão. Conclui-se que B. decumbens é mais competitiva com o feijão que B. hrizantha. Na safra da seca, a utilização de 7,81 g ha-1 de fluazifop-p-butil no consórcio com B. decumbens proporciona rendimento de grãos de feijão equivalente ao do monocultivo. O consórcio com B. brizantha dispensa o uso do herbicida. Na safra das águas, independentemente da espécie de braquiária, é necessária a aplicação de 31,25 g ha-1 de fluazifop-p-butil. To evaluate the effect of fluazifop-p-butyl doses on the performance of bean intercropped with brachiaria species, an experiment was conducted in Coimbra, MG, during the 2007 dry season and 2007-2008 rainy season crops. The experiment was arranged in a randomized block design with four replications. The treatments were set up in a factorial design, involving two species of grass (Brachiaria brizantha and B. decumbens), six doses of fluazifop-p-butyl (0, 7.81, 15.62, 31.25, 62.50, and 125.00 g ha-1), plus the monoculture of both cultures. The common bean plant was planted at 0.5 m between rows, with the brachiaria seeds being sown in the same row of the bean plant. In the intercropping systems, in addition to fluazifop-p-butyl, fomesafen (125 g ha-1) and bentazon (336 g ha-1) were used. A mixture of fomesafen (125 g ha-1) and fluazifop-p-butyl (100 g ha-1) was applied to the monoculture bean. The final plant stand and the bean yield were evaluated with the primary components. Data were submitted to analysis of variance; the effects of the brachiaria species and the crop were studied by the F test and the effects of the fluazifop-p-butyl doses, by regression analysis. It was concluded that B. decumbens is more competitive with the beans than B. brizantha. In the dry season, the use of 7.81g ha-1 of fluazifop-p-butyl in the intercropping with B. decumbens provides a bean yield equivalent to that of the monoculture. Intercropping with B. brizantha does not require the use of herbicide. In the rainy season, regardless of the brachiaria species, 31.25 g ha-1 of fluazifop-p-butyl must be applied.

RESUMO - O objetivo deste trabalho foi avaliar a composição bromatológica da forragem produzida a partir da parte aérea de plantas remanescentes da colheita de minimilho, em diferentes épocas de semeadura e idades de corte das plantas. O experimento foi realizado na fazenda experimental da UNIMONTES, localizada no município de Janaúba – MG. Os tratamentos foram dispostos em esquema fatorial 3 x 5, envolvendo três épocas de semeadura (agosto, dezembro e abril) e cinco idades de corte das plantas remanescentes (0, 8, 16, 24 e 32 dia após a colheita das espigas). O delineamento experimental utilizado foi de blocos ao acaso com quatro repetições. As parcelas foram formadas por quatro fileiras de milho, espaçadas de 0,9 m entre si, com 5,0 m de comprimento. As avaliações foram realizadas utilizando-se as duas fileiras centrais, desprezando-se 0,5 m de cada extremidade. A colheita das miniespigas foi realizada manualmente 2 dias após a emissão dos estilo-estígmas nas três épocas de plantio. As características avaliadas na forragem produzida a partir da parte aérea das plantas remanescentes foram o teor de proteína bruta, extrato etéreo, cinzas, matéria seca, matéria orgânica, fibra em detergente ácido, fibra em detergente neutro, lignina, hemicelulose, celulose e carboidratos não fibrosos. Os resultados obtidos permitiram concluir que há um incremento, para lavouras semeadas em agosto e em abril, nos valores de matéria seca, matéria orgânica e FDN e uma redução nos valores de cinzas e FDA das plantas remanescentes com o passar do tempo.Palavras chave: forragem, milhos especiais, Zea mays.CHEMICAL ANALYSIS OF BABY CORN IN DIFFERENT TIMES OF SOWING AND HARVESTING AGES OF REMAINING PLANTSABSTRACT - The aim of this study was to evaluate the chemical composition of baby corn crops at different times of sowing and harvesting ages of remaining plants in the northern region of Minas Gerais. The experiment was conducted at the experimental farm of UNIMONTES, located in Janaúba-MG. The treatments were arranged in a 3 x 5 factorial, involving three sowing dates (August/2009, December/2009 and April/2010) and cutting ages of the remaining plants (0, 8, 16, 24 and 32 days after ear harvesting). The experimental design was a randomized blocks with four replications. The plots were four 5 m long rows formed by maize spaced 0.9 m apart, using the two central rows to be examined. The chemical characteristics evaluated were: dry matter, organic matter content, ash, ether extract, crude protein, NDF, ADF, lignin, cellulose, hemicelluloses and NFC. The results showed that there is an increase for crops sown in August and April, in the amounts of dry matter, organic matter and NDF and a reduction in the amounts of ash and FDA re-maining plants over time.Keywords: remaining plants, special maize, Zea mays.

Com o objetivo de avaliar a época de semeadura e os efeitos da dessecação da Brachiaria decumbens em consórcio com duas cultivares de feijão (Phaseolus vulgaris L.), foi conduzido um experimento, em Coimbra, MG, em esquema fatorial envolvendo cultivares de feijão (Ouro Vermelho e VC3), duas épocas de semeadura da braquiária (simultânea e na capina do feijão), três tipos de dessecação (sem dessecação, Carfentrazone-ethil e Paraquat), mais dois tratamentos adicionais: os monocultivos do feijão e da braquiária, em DBC com quatro repetições. O feijoeiro foi plantado com semeadora mecanizada, no espaçamento de 0,50 m entre linhas. A braquiária foi semeada com semeadora manual, sempre nas entrelinhas do feijoeiro. Foram avaliados o estande final de plantas e o rendimento de grãos do feijão e a biomassa seca da parte aérea da braquiária, aos 15 e aos 60 dias após a colheita do feijão. Concluiu-se que a cultivar Ouro Vermelho é mais indicada para o consórcio com B. decumbens na safra das águas que a VC3. O retardamento da semeadura da braquiária proporciona maior rendimento de grãos do feijão, mas prejudica a produção de biomassa seca da forrageira. A dessecação na pré-colheita não influencia a produtividade do feijoeiro, mas, quando é realizada com paraquat, prejudica a produção de biomassa seca da forrageira. In order to evaluate different sowing dates and the effect of desiccation on Brachiaria decumbens intercropped with two beans cultivars (Phaseolus vulgaris L.), an experiment was conducted in Coimbra, MG in a factorial design involving two bean cultivars (Ouro Vermelho and VC3), two sowing dates (simultaneous and during bean weeding), three desiccation types (without desiccation, Carfentrazone-ethyl and Paraquat), plus two additional plantings of monoculture bean and brachiaria in DBC with four replications. The beans were seeded by mechanized planting with 0.50 m spacing between the rows. Brachiaria was sown by manual planting between the bean rows. We evaluated the final stand and grain yield of the beans, and the dry biomass of the brachiaria shoots, at 15 and 60 days after the bean harvest. It was concluded that the cultivar Ouro Vermelho was most suitable for intercropping with B. decumbens in the rainy season. Sowing brachiaria after weeding the beans increased the grain yield of the beans, but hindered the production of dry biomass in the brachiaria shoots. Pre-harvest desiccation does not influence the grain yield, but when performed with Paraquat it again hinders the production of dry biomass in brachiaria shoots.

A consorciação de culturas anuais com o cafeeiro é realizada desde a introdução da cafeicultura no Brasil. Entretanto, os últimos resultados disponíveis foram obtidos com cultivares antigos e espaçamentos ultrapassados. Com o objetivo de avaliar o efeito do número de linhas de plantas e da dose de adubação NPK do feijoeiro intercalado ao cafeeiro, foram conduzidos dois experimentos de campo na Universidade Federal de Lavras, um em lavoura em formação (cv. Topázio) e outro em lavoura recepada (cv. Acaiá Cerrado), em duas épocas de plantio (das águas e da seca). O delineamento experimental foi blocos casualizados, com três repetições, sendo os tratamentos distribuídos em esquema fatorial 4 x 4 + 1, envolvendo quatro números de linhas intercalares de feijoeiro (uma, duas, três e quatro) e quatro doses de adubação (0, 50, 100 e 150% da adubação NPK recomendada para o monocultivo), mais um tratamento adicional (o monocultivo do cafeeiro ou do feijoeiro). Concluiu-se que o aumento do número de linhas de feijoeiro elevou o rendimento de grãos da leguminosa em cultivo intercalar ao cafeeiro, independentemente da dose de adubação, do tipo de manejo da lavoura (formação ou recepa) e da época de plantio, mas reduziu o incremento no diâmetro do caule do cafeeiro em formação, a emissão de nós e o crescimento dos ramos plagiotrópicos, tanto no cafeeiro em formação quanto no recepado. O emprego da adubação NPK em até 150% do equivalente à dose recomendada para o monocultivo não influenciou o rendimento de grãos do feijoeiro intercalado ao cafeeiro. Intercropping of annual crops with coffee crop has been used since the introduction of coffee cultivation in Brazil. However, the last available results have been obtained with old cultivars and exceeded distance between lines. Aiming to study the effect of row numbers and NPK doses applied to bean intercropped with coffee trees, two field experiments were conducted at the Federal University of Lavras. The experiments were carried out in two commercial coffee crops: establishing cv. Topázio and cv. Acaiá stumped at 40 cm from the soil level. Both coffee crops were intercropped with bean in the dry and the rainy seasons. The experiments were arranged in randomized blocks design, with three replicates and a 4 x 4 + 1 factorial scheme, involving four numbers of intercalar rows of bean (one, two, three and four) and four doses of the NPK fertilization recommended for the bean monoculture (0, 50, 100 and 150%), and an additional treatment (monoculture of coffee or bean). The results allowed to conclude that the increase in the number of bean rows increased the legume grain yield in intercropping with coffee, regardless of the fertilization dose, the crop management (establishing or stumping) and year season, but reduced the increase in stem diameter of the establishing coffee crop, node emission and growth of plagiotropic branches both in the establishing and stumping coffee plants. NPK fertilization equivalent to up to 150% of the dose recommended for bean monoculture did not influence grain yield of the legume intercropped with coffee plants.

O Tifton 85 é uma forrageira de alto valor nutritivo, recomendada para pastejo, fenação e silagem, podendo ser considerada uma espécie daninha, principalmente em áreas de cultivos agrícolas e produção de sementes de outras forrageiras, devido a sua fácil propagação e seu rápido desenvolvimento. Este experimento foi proposto com o objetivo de avaliar a tolerância de plantas de Tifton 85 a doses crescentes de glyphosate em duas épocas diferentes. O experimento foi conduzido em vasos de polietileno com capacidade de 10 L, em delineamento experimental de blocos casualizados, no esquema fatorial 2 x 8, sendo duas épocas de aplicação (inverno e verão) e oito doses de glyphosate (0, 270, 540, 1.080, 2.160, 3.240, 4.320 e 5.400 g ha-1), com quatro repetições. Para cada época de aplicação, o controle das plantas de Tifton 85 foi feito aos 15, 30 e 60 DAA (dias após aplicação). Obteve-se controle superior a 90% de Tifton 85 a partir de 2.636,72 g ha-1 de glyphosate em aplicação realizada no inverno e de 3.607,03 g ha-1 em aplicação no verão. Os resultados evidenciaram a alta tolerância do Tifton 85 ao glyphosate e o maior controle das plantas expostas a esse herbicida em épocas mais frias do ano (inverno), quando em comparação com as plantas expostas ao herbicida no verão. Tifton 85 is a type of forage of high nutritive value, recommended for grazing or hay and silage production. It can be considered a weed, mainly in agricultural and forage seed production areas, probably due to its easy propagation and fast development. Thus, this experiment aimed to evaluate Tifton 85 tolerance to increasing levels of glyphosate during two different seasons. The experiment was arranged in a completely randomized block design with four replications in a 2 x 8 factorial arrangement, and pulverization in two seasons (winter and summer) and eight glyphosate levels (0; 270; 540; 1,080; 2,160; 3,240; 4,320; and 5,400 g ha-1). The experiment was carried out in polyethylene pots with 10L capacity. For each season, control of the Tifton 85 plants was performed at 15, 30 and 60 DAA (days after application). Around 90% of Tifton 85 plant control was observed with 2,636.72 g ha-1 of glyphosate in the winter and 3,607.03 g ha-1 of glyphosate in the summer. The results obtained showed that Tifton 85 is highly tolerant to glyphosate and control is more efficient in the winter than in the summer.