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The study aimed to assess the impact of mixed silages of biomass sorghum and BRS Capiaçu with cactus pear on the fermentative profile and nutritional value. The silages included forage sorghum cv. Volumax, biomass sorghum cv. ‘BRS 716,’ BRS Capiaçu grass, a mix of 60% biomass sorghum ‘BRS 716’ with 40% Opuntia ficus indica Mill (‘Gigante’) cactus pear (based on fresh matter), and a mix of 60% BRS Capiaçu grass with 40% Opuntia ficus indica Mill (‘Gigante’) cactus pear (based on fresh matter). The experiment followed a randomized experimental design with five treatments and eight repetitions. The highest gas losses (P

This study aimed to assess the interference and threshold level (TL) of Sida rhombifolia, the arrowleaf sida, competing with different soybean cultivars. The treatments comprised different soybean cultivars (NS 6909, NA 5909, DM 5958, Brasmax ELITE, Brasmax LANÇA, and SYN 13561) and densities of arrowleaf sida plants per square meter (m-2) (0, 2, 3, 4, 9, 15, 16, 23, 22, and 58; 0, 2, 3, 3, 6, 6, 10, 11, 18, and 47; 0, 3, 4, 7, 8, 10, 11, 13, 15, and 24; 0, 1, 4, 6, 12, 18, 19, 31, 44, and 50; 0, 4, 5, 6, 9, 13, 17, 20, 20, and 47; 0, 2, 3, 5, 9, 11, 15, 18, 29, and 30, respectively) for each cultivar. Cultivars NS 6909, NA 5909, and Brasmax Lança were more competitive than DM 5958, Brasmax Elite, and SYN 13561. The TL values varied from 0.55 to 0.95 plants m-2 for cultivars NS 6909, NA 5909, and Brasmax Lança, which exhibited greater competitiveness with arrowleaf sida. The lowest values of TL varied from 0.26 to 0.61 plants m-2 for cultivars DM 5958, Brasmax Elite, and SYN 13561, which had less competitiveness with weed. Highlights • The rectangular hyperbola model adequately estimates the grain yield losses of soybean cultivars. • The density of arrowleaf sida plants was the variable that best fitted the rectangular hyperbola model. • Soybean cultivars NS 6909 IPRO, NA 5909 RG, and Brasmax Lança IPRO are the most competitive in the presence of arrowleaf sida. • The levels of economic damage decrease with the increase in grain yield, in the soybean price, with the reduction in the cost of controlling arrowleaf sida and the herbicide efficiency.

Among the forage species, especially in semiarid ecosystems, cactus pear is exceptional because of its high tolerance to adverse conditions and high productivity. Due to this alone, several studies have been conducted to identify the main technologies for this crop. Despite being consolidated and integrated, the cactus pear production system has limited accessibility, technical assistance, and availability of information for those dedicated to its production. This study aimed to present a digital platform, website, and applications to provide technical information on the cactus pear and demonstrate the efficiency of these applications through experimental data. On this digital platform, applications were made available for predicting the productivity of cactus pear using artificial neural networks (ANN) on a computer with routines in the R software and by simple linear regression (SLR) on smartphones on the Android system of the MIT App Inventor 2 platform. In addition, using the smartphone app, it is possible to obtain the cladode area through multiple linear regression (MLR). It is also possible to obtain the estimates of the experimental plot sizes by the maximum modified curvature, linear and quadratic methods with plateau response, relative information, comparison of variances, and convenient plot size. The platform provides technical information associated with the cactus pear crop from different sources (dissertations, theses, articles) and formats (video classes and teaching resources), offline for applications, and online with download for publications, dissertations, theses and articles, video classes, and several didactic resources. The biomathematical models integrated with the applications were highly precise in predicting the phenomena, in which the variation explained by the models in the prediction of responses for future observations had R² values of 0.95, 0.72, and 0.92, respectively, for productivity with computer-ANN and smartphone-SLR, and for the cladode area with a smartphone - MLR.

Abstract The objective of this work was to evaluate the genetic dissimilarity between soybean cultivars and genotypes for the selection of parents, as well as to propose a new method for using Kohonen’s self-organizing maps (SOMs) and to test its efficiency through Anderson’s discriminant analysis. The morphoagronomic descriptors of soybean cultivars and genotypes were evaluated. For data analysis, SOM-type artificial neural networks were used. The proposed method allowed the determination of the best network architecture in a nonsubjective way. Furthermore, at the beginning of training, it was possible to mitigate the randomness effect of the synaptic weights on the formed clusters. Six dissimilar clusters were formed; therefore, there is genetic dissimilarity between soybean cultivars and genotypes. Cultivars C25, C8, and C13 can be combined with C36, C31, C32, and C33 because they show good yield-related attributes and high dissimilarity. The proposed methodology is advantageous in comparison with the use of traditional SOMs, besides being efficient due to clustering consistency according to Anderson’s discriminant analysis.

Introducción: En las últimas décadas, el área de dispersión natural de P. nitens, estuvo sometida a un cambio en el uso de la tierra. Se expandió la frontera agropecuaria, a expensas del bosque nativo, con la incorporación de sistemas productivos que utilizan altas dosis del herbicida glifosato. Se desconoce el el grado de tolerancia de la especie al herbicida, y su respuestas fisiológicas. Objetivo: Evaluar las respuestas bioquímicas y fisiológicas de Pterogine nitens a la deriva simulada de glifosato. Métodos: Hicimos ensayos en invernáculo, con plantas de un año de edad, en macetas. Simulamos la deriva de glifosato, en dosis de 0,65 y 130g e.a. ha-1. Veinte días después de la aplicación, medimos las concentraciones de shikimato, pigmentos fotosíntéticos, y la composición mineral. Resultados: El glifosato incrementó las concentraciones de shikimato, y disminuyó las concentración de pigmentos fotosintéticos. También redujo las cocentraciones de potasio, magnesio, calcio, zinc, manganeso y hierro. Conclusiones: El glifosato altera la etapa fotoquímica de la fotosíntesis, al diminuir la concentración de pigmentos fotosintéticos. También interfiere con la homeostasis de macro y micronutrientes.

The pineapple belongs to the family Bromeliaceae and is a slow-growing succulent monocot with a reduced superficial root system. For this reason, the interference of weeds in competition with this crop can cause significant losses to the production. One of the bases to elaborate a control strategy is the knowledge of the diversity of weeds that occur in the cultivated areas. The objective of this study was to identify the weed community during pineapple growth in a semi-arid climate region of Brazil. Weeds were collected 60, 120, 180, 240, 300, and 360 days after planting (DAP) the pineapple. These collections were made in three different plots every two months until floral induction, composed of three pineapple cultivars. The weed community found in the irrigated pineapple field, in semi-arid climate conditions, was mostly composed by species belonging to the families Amaranthaceae, Asteraceae, Convolvulaceae, Fabaceae, Malvaceae, and Poaceae. The highest diversity of weed species was found at 60 DAP. The species Ipomoea acuminata was present throughout the development of the pineapple and showed the highest importance value index in most of the periods evaluated during the pineapple growth.

The objective was to evaluate the minimum size of experimental plots for the common bean (Phaseolus vulgaris L.) using the modified maximum curvature method. The experiment consisted of a uniformity trial with the cultivar BRSFC-402 sown at a spacing of 0.5 m between plant rows and 10 plants per meter within the row. 20 central rows measuring 20 m in length were considered for measurements, totaling 4,000 plants on an area of 200 m2. Final bean stand (FS), mean number of pods per plant (NPP), mean number of grain per pod (NGP), mean 100-grain weight (M100), and grain yield (kg ha-1) were evaluated. At evaluations, each row with 10 plants was considered a basic unit (0.5 m2), amounting to 400 basic units whose dimensions were combined into 14 plot shapes. The methods of relative information and modified maximum curvature were used to obtain the best shape and the most appropriate plot size, respectively, for experimental evaluation with common bean. Using these methods, and considering that the optimum plot should enable an efficient evaluation of all evaluated characteristics, the appropriate plot size was five UB (25 plants) in the format with five rows x one UB per row. Highlights • Support for experimental evaluation of common beans under edaphoclimatic conditions in the northern region of Minas Gerais • Experimental plots with five basic units ensure maximum precision for joint evaluation of the main phenotypic descriptors of common beans. • The characteristics mass of 100 grains and productivity were associated with the smallest and the largest plot sizes, respectively.

The objective was to evaluate the structural, yield and nutritional characteristics of biomass sorghum BRS 716 managed in different row planting spacing and harvest age in a semiarid region of Brazil. Three row spacing (45, 70 and 90 cm; plots) and four maturity at harvest (70, 100, 130 and 160 days; subplots) were evaluated following a randomized block design in a 3 x 4 split plot arrangement, with eight blocks. The useful area was 3 x 15 m. Variation in soil fertility in the area was the blocking factor. There was interaction between row spacing and maturity at harvest (P < 0.05) on plant height (P = 0.01), dry matter yield (DMY; P < 0.01) and proportion of senescent material (P = 0.01). The DMY observed at the age of 160 days and spacing of 90 cm was 41.40% higher than the DMY at the same age and in spacings of 45 and 70 cm (mean of 21.45 t/ha). As the maturity at harvest increased, there was a reduction in the crude protein content (P < 0.01), potential degradability (P < 0.01) and effective degradability (P < 0.01) of dry matter, and the content of non-fiber carbohydrates (P < 0.01), total digestible nutrients (P < 0.01) and the readily soluble fraction (P < 0.01) of the dry matter increased. Considering the yield and nutritional characteristics of biomass sorghum BRS 716 managed in the semiarid region for silage production, the row spacing of 90 cm and the maturity at harvest of 160 days after planting are recommended.

The search for alternatives that enable the improvement of the soil water retention capacity should focus on a better water use by cultivated plants. This study aimed to evaluate the effect of natural tree resin rates and irrigation levels on the cotton (intermediate cycle) and wild radish (short cycle) crops. Two experiments were conducted in a completely randomized design, in a 5 × 5 factorial arrangement, with three replications and five tree resin rates (0, 0.67, 1.33, 2.00 and 2.67 g plant-1), five soil water tensions (15, 30, 45, 60 and 75 kPa) for cotton plants and five irrigation water levels (40, 60, 80, 100 and 120 % of the ETc) for wild radish plants. The plant height, stem diameter and number of leaves were evaluated at 93 days after sowing (DAS) for the cotton plants; while the plant height, root diameter and number of leaves were evaluated at 30 DAS for the wild radish plants, as well as quantified the shoot and root dry weights of both plant species. The application of tree resin reduces the susceptibility of the crop to water deficit, being 2.7 g plant-1 the highest recommended rate to improve the plant development. The use of tree resin increases the water-use efficiency in cotton and wild radish crops in up to 0.68 g L-1 and 69.6 g L-1, respectively.

The objective of this study was to evaluate the effects of two grazing management strategies on structural, productive and nutritional parameters of Marandu grass (Urochloa brizantha cv. Marandu). A completely randomized block design with two pasture management strategies and eight replications (blocks) was used. The grazing management strategies were: (1) low intensity rotational grazing (LI), with a pre-grazing sward height of 40 cm and a post-grazing sward height of 24 cm, i.e., a defoliation intensity of 50%; (2) High intensity rotational grazing (HI), with a pre-grazing sward height of 40 cm and a post-grazing sward height of 10 cm (±70% defoliation intensity). Pastures were sampled before and after grazing for estimation of forage mass, forage accumulation rate, structural characteristics, nutritional value and dry matter intake. The LI strategy resulted in higher dry matter production than HI before (18.33%) and after grazing (49.06%), increasing pre-grazing forage density by 13.21% (P < 0.05). The production of potentially digestible dry matter was highest (P < 0.05) in LI strategy (21.3% before and 39.6% after grazing, respectively). Higher post-grazing green forage mass (45%) increased the residual crude protein in LI. The LI management strategy increased forage mass production and can be used in Marandu grass pastures.

Prediction models may contribute to data analysis and decision-making in the management of a crop. This study aimed to evaluate the feasibility of predicting the yield of ‘Prata-Anã’ and ‘BRS Platina’ banana plants by means of artificial neural networks, as well as to determine the most important morphological descriptors for this purpose. The following characteristics were measured: plant height; perimeter of the pseudostem at the ground level, at 30 cm and 100 cm; number of live leaves at harvest; stalk mass, length and diameter; number of hands and fruits; bunches and hands masses; hands average mass; and ratio between the stalk and bunch masses. The data were submitted to artificial neural networks analysis using the R software. The best adjustments were obtained with two and three neurons at the intermediate layer, respectively for ‘Prata-Anã’ and ‘BRS Platina’. These models presented the lowest mean square errors, which correspond to the higher proximity between the predicted and the real data, and, therefore, a higher efficiency of the networks in the yield prediction. By the coefficient of determination, the best adjustments were found for ‘Prata-Anã’ (R² = 0.99 for all the network compositions), while, for ‘BRS Platina’, the data adjustment enabled an R² with values between 0.97 and 1.00, approximately. Yield predictions for ‘Prata-Anã’ and ‘BRS Platina’ were obtained with high efficiency by using artificial neural networks.

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.

Culturing of sweet sorghum is being considered as an excellent option for ethanol production, from an agronomical and industrial point of view. At present, information regarding the best soil water tension for beginning sweet sorghum irrigation is not available; hence, this study aimed to determine the adequate soil water tension under field conditions for beginning irrigation of four cultivars of sorghum. Two experiments were conducted at Nova Porteirinha, MG, in a randomized block design with sub-subdivided plots having four replications. Each experiment comprised six treatments of soil water tension (plots)-20, 40, 60, 80, 100, and 120 kPa-for resuming sweet sorghum irrigation, and four sweet sorghum cultivars (subplots)-BRS 508, BRS 509, BRS 511, and CMSXS647. After planting, the soil water level in the plots was elevated to field capacity (10 kPa), and then the treatments were applied. During treatment application, irrigation was resumed when the soil water tension reached the limit established in order to elevate the soil water tension to 10 kPa. The amount of water replaced during each irrigation was determined by generating a soil water retention curve for the experimental area. The following parameters were evaluated: green mass production, juice volume, soluble solids (Brix), and tons of Brix per hectare (TBH). The different soil water tensions and cultivars, agricultural year, and interaction between tension and year significantly affected (p ? 0.05) the characteristics evaluated, according to the F test. The agronomical characteristics of the evaluated cultivars showed linear relationship with water supply in the soil. According to TBH, irrigation of sweet sorghum needs to be performed when the soil tension reaches 20 kPa. The TBH values did not differ significantly among the four cultivars at the 5% significance level according to Tukey test.

Abstract The estimation of pineapple total leaf area by simple, fast and non-destructive methods allow inferences related to carbon fixation estimative, biotic and abiotic damages and correlating positively with yield. The objective was to estimate D leaf area and total leaf area and of ‘Pérola’ pineapple plants from biometric measurements. For this purpose, 125 slips were selected and standardized by weight for planting in pots. Nine months after planting in a greenhouse, the plants were harvested to evaluate the total leaf area of the plant, D leaf area and D leaf length and width using a portable leaf area meter. Pearson correlation analysis was made and it was observed significative positive and strong correlation among the studied variables. Then, regression models were adjusted. It was observed that the D leaf area of ‘Pérola’ pineapple can be estimated from the length and width of this same leaf and the total leaf area can be estimated from the D leaf area.

Phytosociological surveys are very important when identifying an invasive community in order to carry out more suitable weed management. The aim of this study therefore, was to identify the main species of weeds in banana plantations, both newly-planted and under production, in the northern region of the State of Minas Gerais, Brazil. For the phytosociological study and characterisation of the weed community, two areas of ‘Prata’ bananas, both of 10 hectares, were evaluated using the method of inventory squares, which were randomly thrown along a zigzag path. The following phytosociological variables were evaluated: frequency, relative frequency, density, relative density, abundance, relative abundance, importance value index, relativeimportance value index and similarity index. In the newly-planted area, 17 species were found, divided into 15 genera and ten families, with the Fabaceae and Poaceae families being prominent. The species with the highest importance indices were: Sida spp. (62.38), Galinsoga parviflora (32.36), Amaranthus hybridus (24.93) and Ipomoea hederifolia (19.61). In the area under production, 12 species, 12 genera and ten families were found, with the Asteraceae family being prominent. The species with the highest relative-importance value indices were: Commelina benghalensis (39.19), Emilia fosbergii (34.42) and Amaranthus hybridus (32.96). Between the two areas, there was a difference in the mean values for density, and for the number of plants with C4 metabolism; five in the newly-planted area, and three in the area under production. The Similarity Index between the two areas was 48.27%, with seven species common to both areas. = O levantamento fitossociológico é muito importante para conhecer a comunidade infestante e, com isso, realizar de forma mais adequada o manejo das plantas daninhas. Objetiva-se com este trabalho identificar as principais espécies de plantas daninhas em áreas de bananicultura recém-implantadas e em produção na região do norte de Minas Gerais. Para caracterização e estudo fitossociológico da comunidade infestante, avaliaram-se duas áreas de banana-prata, ambas com 10 hectares, nas quais se utilizou o método do quadrado inventário, lançado aleatoriamente por meio de um caminhamento em ziguezague. Avaliaram-se as seguintes variáveis fitossociológicas: frequência, frequência relativa, densidade, densidade relativa, abundância, abundância relativa, índice de valor de importância, índice de valor de importância relativa e índice de similaridade. Na área recém-implantada foram encontradas 17 espécies, divididas em 15 gêneros e dez famílias, destacando-se, dentre essas, as famílias Fabaceae e Poaceae. As espécies com maiores índices de importância foram: Sida spp. (62,38), Galinsoga parviflora (32,36), Amaranthus hybridus (24,93) e Ipomoea hederifolia (19,61). No bananal em produção, encontraram-se 12 espécies, 12 gêneros e dez famílias, com destaque para a família Asteraceae. As espécies que apresentaram maiores índices de valor de importância relativa foram: Commelina benghalensis (39,19), Emilia fosbergii (34,42) e Amaranthus hybridus (32,96). Entre as duas áreas houve diferença nas médias de densidade e nos números de plantas com metabolismo C4; na área recém-implantada foram cinco e na área em produção foram três. O Índice de Similaridade entre as duas áreas foi de 48,27%, sendo sete espécies comuns às duas áreas.

The objective of this work was to study the influence of different seeding rates and cultivars over flooded rice yield at the west border of Rio Grande do Sul State. The experimental design was a randomized blocks with four replicates. The treatments were arranged in factorial scheme 4 x 3, in which factor A was the seeding rate (40, 60, 80 and 100kg ha-1) and B the cultivars (BR-IRGA 409, Olimar and Puitá Inta-CL). The increase in seeding rate from 40 to 100 kg ha-1 reduces linearly the tilled number, filled, total grains for panicle and number of panicle per m2. The greater rice grains yield in cultivars Olimar and Puitá Inta-CL is obtained in seeding rate of 66 and 77 kg ha-1 respectively. On the other hand, the yield of cultivar BR-IRGA 409 was not influenced by seeding rate. The yield grain was greater in cultivar Puitá Inta-CL, except with the seeding rate of 80 kg ha-1, in which it was the second most productive cultivar.

Objetivou-se com o trabalho avaliar os efeitos de épocas de emergência das plantas daninhas, azevém e nabo, sobre a cultura da cevada. O experimento foi conduzido em delineamento de blocos casualizados, arranjado em esquema fatorial 2x5, com três repetições. No fator A, foram alocadas as plantas competidoras (azevém e nabo) e no B as épocas de emergência (14 e 07 dias antes, no mesmo dia, 07 e 14 dias depois da emergência da cultura). No início da floração da cevada, foram mensuradas as variáveis: estatura das plantas, número de colmos ou caules, área foliar e matéria seca da parte aérea da cultura e das plantas daninhas. Todas as variáveis avaliadas da cevada apresentaram aumento de valor com o atraso da emergência das plantas daninhas. As espécies, cultivada ou daninhas, que emergiram antes, apresentaram maior habilidade competitiva, dominando o ambiente quando emergiram 14 dias antes uma da outra. Quanto mais tarde ocorrer a emergência das plantas daninhas com relação à cultura, menor é a interferência e, desse modo, maior é a habilidade da cevada em competir com a espécie daninha pelos recursos disponíveis no meio.

The objective of this study was to evaluate different harvest seasons on the seed quality of crambe, cultivar FMS Brilhante. The experiment was carried out at Experimental area of the Montes Claros State University – UNIMONTES in Janaúba-MG, on September 3, 2011. The first raceme harvest was performed 14 days after flowering, when approximately 50% of the plants showed full flowering. The other harvests were performed every six days, making a total of five harvests. Accumulation of thermal units in degrees day during time intervals was also determined. The collected racemes were taken to the Laboratory of Seed Analysis at UNIMONTES, when they remained under ambient conditions until beginning the analyses. Seeds were evaluated as for water content, germination and vigor (dry seed weight, thousand seeds weight, seedling emergence, and emergence speed). The experimental design was completely randomized, with five harvest seasons, which composed the treatments, and four replications. Crambe seeds present post-harvest dormancy. The maximum dry matter accumulation (physiological maturity) occurred 26 days after flowering. In conclusion, the best time to harvest crambe seeds, cultivar FMS Brilhante, with higher physiological quality (maximum germination and vigor) occurs within 14 to 26 days after flowering, which is a thermal sum 1111,1 to 1302, 15 degree day.

The objective of this work was to evaluate the physiological quality of seeds of different cultivars of beans in terms of densities. The experiment was conducted at the Experimental Farm Unimontes in Janaúba, MG, with sowing in March 2011. The experimental design was a randomized block in factorial 4 x 5 with four replications. The treatments consisted of four bean cultivars of different growth habits (Ouro Vermelho, Ouro Negro, BRSMG Madrepérola and Manteigão Vermelho) and five densities (100, 200, 300, 400 and 500 000 plants ha-1). The seeds were evaluated for water content, germination and vigor tests (seedling emergence, speed of emergence index and accelerated aging). Cultivars Ouro Vermelho, Ouro Negro e BRSMG Madrepérola produce better quality seed physiological, relative to cultivate Manteigão Vermelhão. Increasing the seeding rate did not affect the physiological quality of seeds of bean cultivars, with the exception of Madrepérola, where the population density up to 290 000 plants ha-1 is suitable for production of quality seeds under the conditions studied.

The objective of this study was to evaluate the performance of Agrotechnological two varieties of cane sugar influenced by different times of deletions irrigation and fertilization levels. The characteristics evaluated were: plant height (m), stem diameter (mm), number of tillers m- 1, Brix broth, sugar cane Pol, Pol broth, Sugar reducer, and overall productivity. The experiment was conducted in the Experimental Farm area Unimontes in Janaúba in northern Minas Gerais. The experimental design was a randomized complete block design with three replications in a split plot (2 x 3 x 6) , two varieties of cane sugar, RB85 and 5453 SP80 1816, three different times suppression of irrigation (DIAP) and six different levels of NK fertilization. Data were subjected to analysis of variance, and when significant differences were the F test was performed to compare the means by Scott Knott (p

This study aims to evaluate the morphogenetic characteristics of three cultivars of Brachiaria brizantha subjected to nitrogen fertilization. The design was a randomized block in factorial arrangement 4x3; three cultivars of B. brizantha - Marandu, Piatã, Xaraés and four nitrogen levels - 0, 80, 160 and 240 kg/ha, with three replications. The experimental units consisted of plastic pots filled with 5 dm3 of soil. Thereupon the establishment fertilization, varieties were sowed directly in the pots, leaving, after thinning, five plants per pot. Forty-five days after planting, it was done a standardization cut at 10 cm tall. Nitrogen levels were distributed according to the treatments, divided in three applications. The morphogenetic characteristics were evaluated in three tillers per sampling unit and data were submitted to analysis of variance and regression. For all evaluated characteristics there was no interaction between factors cultivar and nitrogen levels, verifying only the effects of nitrogen on the variables leaf appearance rate and phyllochron. The dose 240 kg/ha of N corresponds to the greater leaf appearance rate. Cultivar Marandu shows the higher leaf blade: pseudostem and ratio of leaf elongation rate and elongation pseudostem, which favors higher forage quality.

This study aims to evaluate the morphogenetic characteristics of three cultivars of Brachiaria brizantha subjected to nitrogen fertilization. The design was a randomized block in factorial arrangement 4x3; three cultivars of B. brizantha - Marandu, Piatã, Xaraés and four nitrogen levels - 0, 80, 160 and 240 kg/ha, with three replications. The experimental units consisted of plastic pots filled with 5 dm3 of soil. Thereupon the establishment fertilization, varieties were sowed directly in the pots, leaving, after thinning, five plants per pot. Forty-five days after planting, it was done a standardization cut at 10 cm tall. Nitrogen levels were distributed according to the treatments, divided in three applications. The morphogenetic characteristics were evaluated in three tillers per sampling unit and data were submitted to analysis of variance and regression. For all evaluated characteristics there was no interaction between factors cultivar and nitrogen levels, verifying only the effects of nitrogen on the variables leaf appearance rate and phyllochron. The dose 240 kg/ha of N corresponds to the greater leaf appearance rate. Cultivar Marandu shows the higher leaf blade: pseudostem and ratio of leaf elongation rate and elongation pseudostem, which favors higher forage quality.Este estudo teve como objetivo avaliar as características morfogênicas de três cultivares de Brachiaria brizantha submetidos à adubação nitrogenada. O delineamento foi em blocos casualizados em esquema fatorial 4x3; três cultivares de B. brizantha - Marandu, Piatã, Xaraés e quatro níveis de nitrogênio - 0, 80, 160 e 240 kg/ha, com três repetições. As unidades experimentais constaram de vasos plásticos preenchidos com 5 dm3 de solo. Logo após a adubação de estabelecimento, as três variedades foram semeadas diretamente nos vasos, deixando, após o desbaste, cinco plantas por vaso. Quarenta e cinco dias após o plantio, foi feita uma padronização de corte de 10 cm de altura. As doses de nitrogênio foram distribuídas de acordo com os tratamentos, divididas em três aplicações. As características morfogênicas foram avaliadas em três perfilhos por unidade de amostragem e os dados foram submetidos à análise de variância e regressão. Para todas as características avaliadas, não houve interação entre os fatores cultivar e doses de nitrogênio, verificando-se apenas os efeitos do nitrogênio sobre a taxa de aparecimento foliar e filocrono. A dose de 240 kg/ha de N corresponde à maior taxa de aparecimento foliar. O cultivar Marandu apresenta maior relação lâmina foliar: pseudocolmo e razão entre taxa de alongamento foliar e alongamento de pseudocolmo, favorecendo a melhor qualidade da forragem.

Objetivou-se neste trabalho avaliar as características tecnológicas de duas variedades de cana-de-açúcar submetidas a diferentes níveis de adubação e supressões de irrigação. O experimento foi instalado na Fazenda Experimental da Universidade Estadual de Montes Claros, em Janaúba-MG. O delineamento utilizado foi o de blocos casualizados, três repetições, em parcelas subdivididas (2 x 3 x 6), sendo na parcela duas variedades de cana-de-açúcar, RB85-5453 e SP80-1816, com três épocas de supressão de irrigação e precipitação após emergência dos perfilhos (DIAC), caracterizadas aos 165, 195 e 225 dias, e na subparcela adubou-se com seis níveis de adubação mineral, 1 (0 kg ha-1 de N e K2O), 2 (14 kg ha-1 de N e 33 kg ha-1 de K2O), 3 (29 kg ha-1 de N e 66 kg ha-1 de K2O), 4 (43 kg ha-1 de N e 100 kg ha-1 de K2O), 5 (57 kg ha-1 de N e 133 kg ha-1 de K2O) e 6 (71 kg ha-1 de N e 166 kg ha-1 de K2O. As variáveis avaliadas foram: Brix, Pol do caldo, Açúcar Total Recuperável (ATR), Pureza e Litros de álcool estimados. Os níveis de adubação influenciaram a qualidade do caldo, obtendo média geral de 24,30 °brix, 20,976% pol do caldo, com a variedade RB85-5453 obtendo maiores valores para todas as variáveis analisadas, a variedade RB85-5453 apresentou maiores teores de ATR, atingindo valores superiores a 189,25 kg t-1. Observaram-se valores em álcool estimados máximo de 115,09 L t-1 da variedade RB85-5453 e mínimo de 90,21 L t-1 na SP80-1816. Com aplicação de 71 kg ha-1 de N e 166 kg ha-1 de K2O de adubação obteve-se melhor desempenho nas condições de realização deste trabalho. Entre as duas variedades estudadas a RB85-5453 é a mais indicada para a região, pois atingiu altos níveis em produção industrial.The objective of this study was to evaluate the technological characteristics of two varieties of cane sugar under different levels of fertilization and irrigation suppression. The experiment was conducted at the Experimental Farm of the State University of Montes Claros, in Janaúba-MG. The experimental design was randomized blocks, three replications in a split plot (2 x 3 x 6), and in part two varieties of cane sugar, RB85-5453 and SP80-1816, with three irrigation season suppression and precipitation after emergency of tiller (DIAC), characterized at 165, 195 and 225 days, and the subplot with six levels of mineral fertilizer, 1 (0 kg ha-1 of N and K2O), 2 (14 kg ha -1 N and 33 kg ha-1 K2O), 3 (29 kg ha-1 N and 66 kg ha-1 K2O), 4 (43 kg ha-1 and 100 kg N ha-1 of K2O ), 5 (57 kg ha-1 and 133 kg N ha-1 K2O) and 6 (71 kg N ha-1 and 166 kg ha-1 of K2O. The variables evaluated were: Brix, Pol of juice, Total Recoverable Sugars (ATR), Purity and liters of alcohol estimated. Nutrient levels influenced the quality of the juice, achieving overall average of 24.30 ° brix, pol 20.976% of the juice. Variety RB85-5453 achieved the highest values for all variables; variety RB85-5453 showed the highest levels of ATR, reaching values higher than 189.25 kg t-1. Estimated values of ethanol were maximum at 115.09 L t-1 for the variety RB85-5453 and minimum at 90.21 L t-1 for variety SP80-1816. The application of 71 kg ha-1 N and 166 kg ha-1 of K2O gave the best performance in the conditions of this study. Variety RB85-5453 was shown the most appropriate for the region because it reached high levels in industrial production.

In pineapple fields, weed competition is exacerbated by the fact that the crop is small and has a very slow vegetative development. The objective of this study was to determine the effects of herbicides on growth, yield and quality of pineapple, cultivar 'Pérola'. The experimental design was in randomized blocks with four treatments and four replications. Treatments consisted of weeding by hoe and the herbicides diuron; fluazifop-p-butyl and atrazine + S-metolachlor applied in post-emergence. The characteristics evaluated monthly during the vegetative stage were stem diameter, D-leaf length, number of leaves, number of emitted leaves and percentage of natural floral induction. In the reproductive phase, evaluations were made of average fruit weight (g) with and without crown, fruits length and diameter, number of slip, slip-sucker and sucker type seedlings, determination of soluble solids and pH in the pulp. There was no effect of herbicide treatment on the vegetative growth characteristics. Stem diameter increased until 330 days after planting, showing a decrease after this period. The D-leaf grew over time in all treatments, although phytotoxicity symptoms were observed after the first application of herbicides. The traits evaluated on the reproductive phase showed no significant differences in response to treatments. Therefore, the use of diuron fluazifop-p-butyl and atrazine + S-metolachlor did not affect growth, yield and fruit quality of pineapple, cultivar 'Pérola'.

O objetivo deste trabalho foi avaliar o efeito do quinclorac nas características anatômicas de folhas e raízes de biótipos de capim‑arroz (Echinochloa spp.), resistente e suscetível a este herbicida, por meio de avaliações micromorfométricas. As plantas foram cultivadas em vasos de plástico com capacidade de 250 cm³. As imagens dos cortes foram obtidas com microscópio de luz equipado com sistema U‑Photo, acoplado à câmera digital conectada a microcomputador. Na seção transversal da lâmina foliar e das raízes, utilizou-se objetiva de 10X, tendo-se avaliado 20 cortes/campos por planta, com dez medições por corte e quatro repetições por tratamento. Observaram-se diferenças entre os biótipos resistente e suscetível, tanto na ausência quanto na presença do quinclorac. O biótipo resistente apresenta lâmina foliar pouco afetada pelo herbicida; no entanto, há modificação na constituição dos tecidos radiculares com a formação mais acentuada de aerênquima. O biótipo suscetível também apresenta formação de aerênquima quando tratado com o quinclorac, mas em quantidade inferior à observada no biótipo resistente.

O levantamento fitossociológico é muito importante para conhecer a comunidade infestante e, com isso, realizar de forma mais adequada o manejo das plantas daninhas. Objetiva-se com este trabalho identificar as principais espécies de plantas daninhas em áreas de bananicultura recém-implantadas e em produção na região do norte de Minas Gerais. Para caracterização e estudo fitossociológico da comunidade infestante, avaliaram-se duas áreas de banana-prata, ambas com 10 hectares, nas quais se utilizou o método do quadrado inventário, lançado aleatoriamente por meio de um caminhamento em ziguezague. Avaliaram-se as seguintes variáveis fitossociológicas: frequência, frequência relativa, densidade, densidade relativa, abundância, abundância relativa, índice de valor de importância, índice de valor de importância relativa e índice de similaridade. Na área recém-implantada foram encontradas 17 espécies, divididas em 15 gêneros e dez famílias, destacando-se, dentre essas, as famílias Fabaceae e Poaceae. As espécies com maiores índices de importância foram: Sida spp. (62,38), Galinsoga parviflora (32,36), Amaranthus hybridus (24,93) e Ipomoea hederifolia (19,61). No bananal em produção, encontraram-se 12 espécies, 12 gêneros e dez famílias, com destaque para a família Asteraceae. As espécies que apresentaram maiores índices de valor de importância relativa foram: Commelina benghalensis (39,19), Emilia fosbergii (34,42) e Amaranthus hybridus (32,96). Entre as duas áreas houve diferença nas médias de densidade e nos números de plantas com metabolismo C4; na área recém-implantada foram cinco e na área em produção foram três. O Índice de Similaridade entre as duas áreas foi de 48,27%, sendo sete espécies comuns às duas áreas.

For adapting well to various soil and climatic conditions in Brazil and the tradition of high consumption, bean plays a key role in feeding the population. Despite the different environmental conditions, there are few specific cultivars for each planting season, particularly when aimed at the production of quality seeds. The objective of this study was to evaluate the physiological potential of bean seeds from five population densities, under the edafoclimatic conditions of Janaúba, northern Minas Gerais. The experiment was conducted on winter crop season, with planting in August 2011. The experimental design was a randomized block in 3 x 5 factorial, with four replicates. The treatments consisted of three cultivars of common bean with different growth types (Ouro Vermelho, Ouro Negro and BRSMG Madrepérola, and five densities (100, 200, 300, 400 and 500 thousand plants ha-1). Seeds were evaluated for water content, germination and vigor (tests of first count, seedling emergence, emergence speed and accelerated aging). From the results, it can be concluded that the bean seeds of the cultivar Ouro Negro present superior physiological potential in relation to the cultivars Ouro Vermelho and BRSMG Madrepérola. Increasing the sowing density up to 300 thousand plants ha-1 is suitable for the production of bean seeds on winter crop season, representing a good alternative for cultivation in the region.

Objetivou-se, neste trabalho, avaliar as características tecnológicas de acúmulo de açúcares e ação da invertase de duas variedades de cana-de-açúcar submetidas a diferentes supressões de irrigação e níveis de adubação. O experimento foi instalado na Fazenda Experimental da Universidade Estadual de Montes Claros, em Janaúba-MG. O solo da área experimental foi classificado como Latossolo Vermelho Distrófico textura média, (LVd); (EMBRAPA, 1999), o delineamento utilizado foi o de blocos casualizados, três repetições, em parcelas subdivididas (2 x 3 x 6) , sendo duas variedades de cana-de-açúcar RB85- 5453 e SP80-1816, três épocas de supressão de irrigação mais precipitação após corte (DIAC) caracterizadas aos 165, 195 e 225 dias, e na subparcela adubouse seis níveis de adubação mineral. As variáveis foram: brix, AR, ART, ATR e umidade. Os níveis de adubação interferiram na qualidade do caldo obtendo uma média geral de 24,30° brix, com a variedade RB85-5453 obtendo maiores valores para todas as variáveis analisadas. Observou-se valor de 0,8% AR na variedade SP80-1816 e mínimo na variedade RB85-5453 com 0,35 %AR, no parâmetro ATR, verificou-se que a variedade RB85-5453 apresentou melhor resultado, tendo possibilidade de atingir teores superiores a 189,25 kg de ATR t-1. O nível 6 de adubação obteve melhor desempenho nas condições de realização deste trabalho. A RB85-5453 é a mais indicada para a região, pois conseguiu altos níveis em produção industrial.

ABSTRACT The objective of this study was to evaluate the effect of the trainer and the adopted daily work on the behavior and performance of horses of the Mangalarga Marchador breed on a horse farm and in racetracks in northern Minas Gerais State, Brazil. Twenty equines and nine trainers from four farms and three competition events of the breed were observed. The experiment was divided into two stages. In the first stage, the animals were observed together with their trainer on the farm, during the daily work, and the behavior reactions were recorded based on scores. The duration of training and the behavior told by the trainer of the animal were recorded in scores. The second stage happened in three competitions of the breed in agricultural fairs. The same observations were made on horse farms, including the behavior of the animal, before and after the trial, as well as the emotional state in the same period. For data analysis, multivariate statistics were used based on the principal components and factor analysis, using the statistical software R (version 3.3.2). From the data analyzed, it was verified that the variables embouchure, behavior and voice of the presenter, and reward and incentive in the competition influenced the reactivity of the animal. Variables of human behavior in training influenced the animal behavior variables in training. The behavior of the trainer and the form of the training, as well as the fact that the trainer is the presenter, interfered in the behavior of the horses on the horse farm and in the competitions, resulting in safer animals. However, the need for time adaptation and training management is necessary for the whole man × animal relation to get better rankings in the race competitions.