Univariate methods for diagnosing nutritional status such as the sufficiency range and the critical level for garlic crops are very susceptible to the effects of dilution and accumulation of nutrients. Therefore, this study aimed to establish bivariate and multivariate norms for this crop using the Diagnosis and Recommendation Integrated System (DRIS) and Nutritional Composition Diagnosis (CND), respectively. The criteria used were nutritional status and the sufficiency range, and then the diagnoses were compared. The study was performed in the region of Alto Paranaíba, MG, Brazil, during the crop seasons 2012 and 2013. Samples comprised 99 commercial fields of garlic, cultivated with the cultivar "Ito" and mostly established in Latossolo Vermelho-Amarelo Distrófico (Oxisol). Copper and K were the nutrients with the highest number of fields diagnosed as limiting by lack (LF) and limiting by excess (LE), respectively. The DRIS method presented greater tendency to diagnose LF, while the CND tended towards LE. The sufficiency range of both methods presented narrow ranges in relation to those suggested by the literature. Moreover, all ranges produced by the CND method provided narrower ranges than the DRIS method. The CND method showed better performance than DRIS in distinguishing crop yield covered by different diagnoses. Turning to the criterion of evaluation, the study found that nutritional status gave a better performance than sufficiency range in terms of distinguishing diagnoses regarding yield.

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Germination does not guarantee plant establishment if there is no efficient and enough reserve mobilization from seeds to the initial seedling growth, mainly in adverse situations. Therefore, this study aimed to evaluate the mobilization of reserves in soybean seeds under water restriction. Four soybean seed lots previously stored for one year were used in the study. To simulate water stress, we used polyethylene glycol (PEG) solutions at concentrations of 0.0, -0.1, and -0.2 MPa. The number of normal, infected and abnormal seedlings were evaluated, along with the number of dead and hard seeds. The radicle, hypocotyl, and cotyledons were separated to determine the dry weight based on the total seed reserve available for mobilization. From this value, the seed reserve reduction, relative dry matter yield, seed reserve reduction rate, and reserve conversion efficiency into dry seedling weight were determined. The increase in water restriction elevates the reserve consumption during the germination process. Vigorous seeds are more efficient in mobilizing and converting grains reserve in dry seedling mass. In less vigorous seeds, mainly those on water restriction, the increase in reserve consumption does not result in conversion into dry seedling mass.

RESUMO: O conhecimento da variabilidade da nutrição de plantas e da produtividade em áreas cultivadas com plantas de milho que apresentam alta produtividade pode fornecer importantes subsídios na racionalização do uso de insumos e auxiliar no manejo da fertilidade do solo. Essa pesquisa tem como objetivo determinar os padrões de extração e de exportação de nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg) e enxofre (S) por lavouras de milho de alta produtividade. Quinze talhões de milho cultivados sob sistema convencional e que apresentavam alto potencial produtivo foram amostrados no ano agrícola 2014/2015 na região do Alto Paranaíba (MG) e avaliaram-se a produtividade e a extração e exportação de N, P, K, Ca, Mg e S. Os acúmulos de N, P, K e S em grãos e extração total tiveram efeitos positivos na produtividade da cultura do milho. A massa de mil grãos foi o componente de produtividade mais importante na definição da produtividade.A extração e exportação de N, P, K e S aumentaram linearmente com o aumento da produtividade. Os resultados fornecem dados importantes sobre a absorção e partição de nutrientes dos híbridos atuais e permitem aprimorar as recomendações de adubação para produção de grãos de milho.ABSTRACT: Knowledge on the variability of plant nutrition and productivity in corn plantations with high productivity may provide important subsidies in the restructuring of inputs and in the management of soil fertility. Current research determines extraction and export standards of nitrogen, phosphorus, potassium, calcium, magnesium and sulfur in high productivity corn plantations. Fifteen corn rows cultivated within the traditional system, featuring high productivity, were sampled in the Alto Paranaíba, MG, Brazil, for the agricultural year 2014/2015, and the productivity, extraction and export of N, P, K, Ca, Mg and S were assessed. Accumulation of these macronutrients in the grains and total extraction had positive effects in corn productivity. Mass of one thousand grains was the most relevant productivity´s component. N, P, K and S extraction and export increased linearly with increase of productivity. Results provide important data on the absorption and partition of nutrients of hybrids and allow the improvement of fertilizing recommendations for corn production.

Bacteria belonging to the genus Bacillus can promote plant growth and suppress plant-parasitic nematode populations. Based on this hypothesis, eight strains of the bacterium (SF 262, SF 264, SF 266, SF 267, SF 268, SF 271, SF 292 and SF 629) were formulated and applied as a seed treatment and/or sprayed on the soil surface with the aim of controlling Pratylenchys brachyurus in common bean under field conditions. The application of the bacterial isolates neither improved the grain yield and the root mass nor reduced the number of nematodes in the soil and in the roots of common bean. Thus none of the isolates of Bacillus spp. evaluated in this work are promising for the control of the lesion nematode on common bean.

Analyses of germination of seeds under artificial stress conditions are tools for a better understanding of the survival and adaptation capacity of species under natural stress conditions. Therefore, the aim of this study was to evaluate the effect of priming on seed germination, on breaking of dormancy, and on the length of Urochloa brizantha seedlings under water restriction and salt stress conditions. A completely randomized experimental design was used with four replications in a 3 × 6 factorial arrangement consisting of 3 germination conditions (water, water restriction with PEG, and salinity with NaCl) and 6 treatments [five priming solutions (distilled water, potassium nitrate, spermidine, gibberellin, and sodium nitroprusside) and a control (unprimed seeds)]. The following determinations were made: seed moisture content after priming (before drying) and after drying the seeds, germination test at seven and twenty-one days after sowing, germination speed index, viability by the tetrazolium test of the seeds remaining from the germination test, and seedling length. Priming is effective in minimizing the negative effects of water restriction and salinity. Use of sodium nitroprusside as a priming solution results in a lower percentage of dormant seeds and greater germination, vigor, and plant development.

The existing literature for the recommendation of fertilizers and diagnosis of the nutritional status of the carrot crop is outdated because it contemplates productivities lower than those currently obtained. The objective of this research was to characterize the nutritional demand of the carrot crop by estimating the dry matter content of the roots, the coefficient of biological utilization of the nutrients and the harvest index of dry matter and of the mineral nutrients, in order to indicate fertilizers according to the desired productivity for winter and summer cultivations. We sampled 210 carrot plots located in the Alto Paranaíba region, Minas Gerais, Brazil, during 2012 and 2013. We determined the content of dry matter of the roots, the coefficient of biological utilization of the nutrients in the roots and leaves and the harvest index of dry matter and nutrients in the crop. Data were grouped in two groups of cultivations: Winter and summer. The harvest index of dry matter and of nutrients was bigger for the winter cultivars. Regardless of the growing season, the N, P, K, Mg and B were retained in greater amounts in the roots. Phosphorus had the highest harvest index, and the Cu, the lowest. The differences were insignificant in the nutritional demand of N, P, Ca, S, B, Cu and Zn between winter and summer cultivars for the average productivity obtained in each season. In the summer cultivars, the carrot accumulates greater amounts of Fe and lower of K, Mg and Mn when compared to winter. The modeling of the nutritional demand of the carrot crop can be carried out depending on the desired productivity and growing season.

High yield corn has an increased demand for micronutrients, which requires updating knowledge of the nutritional demand patterns of the crop, especially under high production conditions. The objective of the currentstudy was therefore to determine the absorption and export patterns of copper (Cu), manganese (Mn), zinc (Zn) and iron (Fe) for high yield corn crops. Fifteen corn fields with high productive potential were sampled in the Alto Paranaíba, region, Minas Gerais, in the agricultural year 2014-2015. The following variables were evaluated: productivity, plant population, rows of grain per ear, grain per row, grain per ear, mass of one thousand grains, vegetation dry mass, dry mass of grains and total dry mass of the plant, besides the accumulation of micronutrients in the vegetative part and grains, and total micronutrient accumulation per whole plant. The grain and Cu, Mn, Zn and Fe harvest indices were also calculated. The data were submitted to descriptive statistics, Pearson coefficient linear correlation was calculated at the to 5% level and submitted to regression analysis. Cu and Zn absorption and export increase linearly with increased productivity. Micronutrient accumulation in high productivity maize is, in decreasing order, in the vegetative part: Fe> Mn> Zn> Cu; while in the grains and in the whole plant: Fe> Zn> Mn> Cu. Zn is the micronutrient with the highest harvest index.