Development of super early genotypes for the dry bean (Phaseolus vulgaris) as affected by nitrogen management.

The super early genotypes (SEG) of dry bean (Phaseolus vulgaris L.) have a shorter life cycle (65-75 days) when compared with the season length of traditional cultivars (90-100 days). Timing of nitrogen top-dressing fertilization could be different because of this reduction in length of the SEG life cycle. This study aimed at characterizing, by using growth analysis and vegetation index, super early genotypes of dry bean development as affected by timing of nitrogen application. Field experiments were conducted in the 2014 and 2015 growing seasons in central Brazil with a randomized block experimental design with split plots scheme and four replicates. The plots comprised the dry bean genotypes (Colibri ? check cultivar, CNFC 15873, CNFC 15874, and CNFC 15875), and subplots comprised applications of N at different timings: 90 kg of N at sowing, 90 kg N at top-dressing; 45 kg of N at sowing plus 45 kg at top-dressing, with urea as the source of N. We also used a control treatment without N application. The CNFC 15874 super early genotype of dry bean had the higher grain yield (2776 kg ha-1) and differed from the CNFC 15873 genotype (2492 kg ha-1). Nitrogen fertilization allowed higher grain yield (2619 kg ha-1, when applied N at sowing, 2605 kg ha-1, when applied N at sowing and at top-dressing, and 2680 kg ha-1, when applied N at top-dressing) than the control, 2360 kg ha-1 (no N fertilization). The time of N fertilization in super early genotype of dry bean did not affect grain yield.

Avaliação do ciclo de vida do sistema de produção soja-girassol no cerrado Brasileiro.

RESUMO: O girassol é uma importante cultura na região de Parecis, no Cerrado brasileiro. Em 2014, a região respondeu pela produção de 232.700 t de grãos, 45% da produção nacional. A produção de girassol provém principalmente de um sistema que tem a soja como cultura principal. A associação entre soja e girassol pode reduzir impactos ambientais devido ao uso compartilhado de recursos. Este estudo desenvolveu uma Avaliação de Ciclo de Vida (ACV) ?do berço ao túmulo? do sistema de produção soja-girassol usado na região de Parecis e comparou seu perfil ambiental ao das monoculturas de soja e girassol. Impactos relacionados ao uso do solo (emissões da mudança de uso da terra e calagem) por cada cultura foram alocados em função do tempo de ocupação do solo. O sistema soja-girassol teve impactos ambientais menores em todas as categorias de impacto quando comparado à monocultura de soja e girassol, com o mesmo rendimento. Reduções importantes foram observadas em ?Mudança do Clima?, ?Acidificação Terrestre? e ?Formação de Material Particulado?. ABSTRACT: Sunflower is an important crop in Parecis region of the Brazilian Cerrado. In 2014 the region accounted for the production of 232,700 tons of sunflower grain, 45% of national production. Sunflower production comes mostly from a system that has soybean as the main crop. The association of soybean and sunflower can reduce environmental impacts due to shared use of resources. This study performed a ?cradle to gate? Life Cycle Assessment (LCA) of the soybean-sunflower production system used in Parecis region and compared its environmental profile to that of the monoculture of these two crops. Impacts related to the use of soil (land use change emissions and liming) by each crop were evaluated according to time of soil occupation criterion. Soybean-sunflower system had lower environmental impacts on every impact category comparing to soybean and sunflower monoculture with the same yield. Important reduction were observed on ?Climate change?, ?Terrestrial acidification? and ?Particulate matter formation? categories.