Resumo -O objetivo deste trabalho foi avaliar, por meio da análise dos componentes principais, a redução na dimensionalidade de atributos químicos e físicos do solo para a compreensão da variabilidade espacial e temporal da produtividade de culturas de grãos. A área experimental, de 54 ha, é manejada em agricultura de precisão há oito anos. Com base em seis mapas de colheita (soja -safra 2000/2001; milho -2001/2002; soja -2002/2003; trigo -2003; soja -2003/2004; e milho -2004/2005), a área foi dividida em três zonas de produtividade de grãos (alta, média e baixa). Foram definidos 15 pontos georreferenciados representativos, para determinação de atributos químicos e físicos do solo, o que totalizou 63 variáveis analisadas. Entre os atributos químicos, o elevado teor de K no solo é o que melhor explica a variabilidade espacial da produtividade das culturas de grãos, provavelmente em razão do desbalanço das relações Ca:K e Mg:K. A zona de baixa produtividade apresentou baixa qualidade física do solo. Neste caso, a infiltração de água no solo, isoladamente, é a variável que melhor explica o desempenho das culturas de grãos. A análise dos componentes principais dos atributos químicos e físicos do solo é estratégia eficiente para explicar a variabilidade espacial e temporal da produtividade de culturas de grãos.Termos para indexação: agricultura de precisão, análise multivariada, variabilidade espacial, variabilidade temporal, zonas de manejo. Principal component analysis of soil chemical and physical attributes limiting grain yieldAbstract -The objective of this work was to evaluate, through principal component analysis, the reduction in the dimensionality of soil chemical and physical attributes in order to understand the spatial and temporal variability of grain crop yield. The experimental area of 54 ha has been managed under precision agriculture for eight years. Based on six grain yield maps (soybean -2000/2001 harvest season; maize -2001/2002; soybean -2002/2003; wheat -2003; soybean -2003/2004; and maize -2004/2005), the area was split in three grain yield zones (high, medium, and low). Fifteen representative geo-referentiated points were defined in order to determine soil chemical and physical attributes, totaling 63 analyzed variables. Among chemical attributes, the high K content in soil is the variable that best explains the spatial variability of grain crop yield, probably due to the imbalance of the Ca:K and Mg:K relations. The low-yield zone had low soil physical quality. In this case, soil water infiltration, solely, is the variable that best explains the performance of the grain crops. Principal components analysis of soil chemical and physical attributes is an efficient strategy to explain the spatial and temporal variability of grain crop yield.

The cultivation of soybean in Brazil experienced an expressive growth in the last decades. Soybean is highly demanding on nitrogen (N) that must come from fertilizers or from biological fixation. The N supply to the soybean crop in Brazil relies on the inoculation with elite strains of Bradyrhizobium japonicum, B. elkanii, and B. diazoefficiens, which are able to fulfill the crop's N requirements and enrich the soil for the following crop. The effectiveness of the association between N2-fixing bacteria and soybean plants depends on the efficacy of the inoculation process. Seed treatment with pesticides, especially fungicides or micronutrients, may rapidly kill the inoculated bacteria, affecting the establishment and outcome of the symbiosis. The development of technologies that allow inoculation to become a successful component of industrial seed treatment represents a valuable tool for the seed industry, as well as for the soybean crop worldwide. In this article, we report the results of new technologies, developed by the company Total Biotecnologia Indústria e Comércio S/A of Brazil, for preinoculation of soybean seeds with bradyrhizobia, in the presence of agrichemicals. Our results demonstrate improved bacterial survival for up to 30 days after inoculation, without compromising nodulation, N2-fixation, and yield in the field.

(1989). a metodologia de lin e binns (1988), de fácil interpretação, foi eficiente em recomendar cultivares de alto rendimento e boa estabilidade, e os materiais mais responsivos, o menor P i e a alta correlação negativa de spearman, entre o rendimento de grãos. Concluiu-se que a metodologia de lin e binns é bastante discriminante e, quando associada ao w i , oferece maior segurança na recomendação de cultivares com maior estabilidade. Palavras-chave:Triticum aestivum L., produção de grãos, adaptabilidade e estabilidade, interação genótipo x ambiente. ABSTRACT meThods For anaLysis oF adapTaBiLiTy and sTaBiLiTy oF wheaT CuLTivars For paraná sTaTe, BraziLThis investigation had the objective to evaluate grain yield adaptability and stability of 17 wheat cultivars (Triticum aestivum L.) for paraná state, Brazil, occording to four different methods. The experiments were carried out in 2007, at different locations of paraná, in complete randomized blocks experimental design, with 4 replicates. The Wricke (1965) methodology indicates stable cultivars, independently of average yield. eberhart and russell (1966) and cruz et al. (1989) methodologies were equally efficient to evaluate stability and indicate cultivars that are stable and also adapted to favorable and unfavorable environments. lin and binns (1988) methodology showed to be of easy interpretation and was efficient to indicate cultivars of high yield and with good stability, where more responsive materials showed a lesser P i , and high negative correlation of spearman between grain yields. it was concluded that LIN and BINNS methodology is very specific and when associated to W i offers more assurance in recommending cultivars for high stability.Key words: Triticum aestivum L., grain yield, adaptability and stability, genotype x environment interaction.

RESUMO Com objetivo de caracterizar os cultivares de milho

Resumo -O enxofre é um componente de proteínas e aminoácidos em plantas, sendo exigido em boa quantidade por leguminosas, pelo alto acúmulo de proteínas nessas espécies. Com isso, este trabalho teve por objetivo verificar a influência de diferentes fontes de enxofre sobre a produtividade de grãos na cultura da soja. O experimento foi instalado na área experimental da Fundação MS, em Maracajú, MS, em três anos consecutivos no delineamento de blocos ao acaso, com quatro repetições, submetidas à análise de variância conjunta. Foram implantadas as cultivares BRS-133 (2002/03 e 2003/04) e CD 202 (2004. Como tratamento foram avaliados: as adições de enxofre na forma de superfosfato simples, MAP sulfurado + Sulfurgran, Sulfurgran, enxofre elementar, gesso granulado, Fosmag 509M6, gesso agrícola a lanço e testemunha, sem a aplicação. A soja responde à aplicação de enxofre em solos das regiões do cerrado brasileiro, sendo necessária, na maioria das vezes, a fertilização com este nutriente para obtenção de altas produtividades. A grande maioria das fontes de enxofre utilizadas foi eficiente em fornecer este nutriente para a soja, com destaque para a aplicação de MAP Sulfurado + Sulfurgran, Formag 509M6 e gesso agrícola a lanço, que promoveram as melhores produtividades de grãos. O enxofre elementar não foi eficiente em disponibilizar S para a cultura.Palavras-chave -Soja. Plantas-efeito do enxofre. Cerrado brasileiro.Abstract -Sulphur is a component of protein and aminoacids in plants, being required in an expressive amount by leguminous, as function of high protein levels in these plants. Then, this work aimed to verify the influence of different sulphur sources on soybean grain yield. The experiment was carried out at the experimental area of Fundação MS, Maracajú, MS, in three consecutive years in a randomized block design with four replications, submitted to variance analysis of group experiments. The cultivars used were BRS-133 (2002/03 and 2003/04) and CD 202 (2004. As treatments, it was evaluated the application of sulfur as Simple Superphosphate, MAP sulphured + Sulfurgran, Sulfurgran, elemental sulphur, granulated gypsum, Fosmag 509M6, agricultural gypsum throwed on surface, and a witness without application. Soybean crop answer is positive to soil applied sulphur in Brazilian cerrado soils, in most of the time to obtain higher grain yield. Most of S sources were efficient to provide this nutrient for soybean, highlighting the applications of MAP Sulphured + Sulfurgran, Formag 509M6 and agricultural gypsum, that promoted the highest soybean grain yield. Elemental sulphur was not efficient to provide available S for the crop.Key words -Soybean. Plants-sulphur effect. Brazilian cerrado.* Autor para correspondência 1 Recebido para publicação em 24/06/2010; aprovado em 02/05/2011 Trabalho de pesquisa realizado na Fundação MS, de Maracajú-MS 2 Fundação MS para pesquisa e difusão de tecnologias agropecuárias, Maracajú-MS, Brasil, dirceu

Montane climates are shaped by high spatial variability that depends on net radiation and synoptic weather, and much on elevation and topographic features of terrain. We measured near-ground meteorological variables using a weather station network during 14 months, in a valley-shaped basin in southeast Brazil, to address the spatiotemporal climate variability at the meso-γ atmospheric scale. The terrestrial climatic gradients were evident in the cross-valley direction of the basin, where the valley tended to warm/wet up at day and cool/dry down at night relatively from the slopes. The temperature at noon showed high variability and decreased at a mean gradients of about −0.7 C (100 m) −1 . The nocturnal air temperature increased with height up to a maximum at about 200 m (the thermal belt), and showed seasonal rates higher/less in dry/wet season of +1.1/+0.2 C (100 m) −1 over the full altitude. The vapour pressure decreased from the valley bottom upwards, in general below −0.5 hPa (100 m) −1 , whereas the wind speed increased at a rate of 0.9 m s −1 (100 m) −1 . We noted significant differential warming along the valley and mountain sides. The middle valley was circumstantially colder at night and warmer at daytime, relatively to the upper catchment, under mean magnitudes below 1.0 C. The west slope at upper catchment was slightly warmer at night, and colder in the afternoon, at magnitudes below 0.5 C, highlighting the control of hills' aspect at daytime, and the sheltering to flow aloft in east side. The cross-valley gradients appeared to be well associated with local circulation, where downslope wind and positive temperature gradients, as well as upslope wind and negative temperature gradients strictly coexisted during the morning. The terrestrial gradients and the thermal circulation were in general dampened by cloudiness and mechanical mixing.

ABSTRACT. The objective of this study was to evaluate the agronomic characteristics of corn seed inoculated with Azospirillum brasilense, grown on black oat and ryegrass straw, and managed under different grazing strategies and doses of nitrogen. The experiment was conducted in Santa Maria, Rio Grande do Sul State, Brazil, during two agricultural seasons (2012/2013 and 2013/2014) in a randomized, complete block design with three replications. In the winter period, black oat and ryegrass straw were managed at different grazing heights by sheep (0.30, 0.20, 0.10 m, conventional grazing, and no grazing) with three doses of nitrogen (0, 50, and 100 kg ha The height of corn plants was greater when they were grown on black oat and ryegrass straw, and the absence of grazing favored productivity. Under drought conditions, the application of nitrogen to the pasture favored corn development, increasing plant height, ear height, and stem diameter. Inoculation with A. brasilense had a positive effect on the characteristics of yield and productivity of corn, independent of growing season and hybrid used.

As cultivares de feijão "TPS Nobre" e "Pérola" foram utilizadas durante a safra de 2001/2002 em Santa Maria -RS, com o objetivo de determinar a melhor época de aplicação e o fracionamento mais adequado da adubação nitrogenada que poderão ser adotados no sistema de plantio convencional. O nitrogênio foi aplicado na semeadura (15kg ha-1 em todos os tratamentos) e em uma única dose aos 14, 21, 28 e 35 DAE, sendo fracionado nas mesmas épocas em duas aplicações: 50% + 50% da dose, 30% + 70% da dose, 70% + 30% da dose. O delineamento experimental utilizado foi o de blocos ao acaso, com parcelas subdivididas. Não foi verificada a interação entre a adubação nitrogenada e a época de aplicação. Além disso, a cultivar "TPS Nobre" obteve um rendimento de grãos 49% superior à cultivar "Pérola". O maior rendimento de grãos foi obtido por meio da aplicação de 100% da adubação nitrogenada aos 21 dias após a emergência, porém bons resultados são obtidos com o fracionamento da adubação nitrogenada (50% 14 DAE + 50% 21 DAE), (70% 14 DAE + 30% 28 DAE) e (30% 21 DAE + 70% 28 DAE). A aplicação nitrogenada após os 28 DAE não apresentou resultados favoráveis à obtenção de elevados rendimentos de grãos.