Custo de produção e indicadores de rentabilidade da cultura do milho safrinha

The objective of this study was to evaluate the production cost and profitability of the second season corn crop in the Medio Paranapanema region, São Paulo State Brazil, under two technological levels (middle and high technology), crop 2008/2009, and compare the results with the 2006/2007 agricultural year. Effective and total operational cost as well as five profitability indicators were used. It was concluded that the high technology production cost for corn crop (direct seedling, sowing during the recommended period, use of simple hybrid seed, application of side-dressing fertilization, and treatment of seeds with different insecticides) was superior to the middle technology production cost (direct seedling, sowing after the recommended time, use of double hybrid seed, and no side-dressing fertilization). However, the average cost was inferior (US$ 8.5), due to a higher yield (4 t). The high technology corn crop was profitable (gross income and profitability index of 14% and 12%, respectively). For the middle technology crop, profitability indexes pointed out that the cropping system needs to be reevaluated by technicians and research institutions, regarding the adequate technical recommendations. Profitability indexes decreased considerably in both cropping systems. It was verified that, in relation to the 2006/2007 harvest period, the total operational cost increased for both technologies, mainly because of the increase of supplies prices.

Desempenho de semeadora-adubadora em função do prepa ro de solo e espa çamento da cultura do milho

The performance of machines and agricultural implements are of fundamental importance, especially when subjected to different types of soil tillage, and have to adapt to these conditions, in order to promote good operational performance. The objective of this study was to analyze the operational performance of a Marchesan Supreme Cop grain drill, equipped with four rows, spaced 0.90 m, according to three types of tillage: conventional tillage (plowing and two harrowing series), reduced tillage (scarification with a roller), and no-tillage, in areas previously seeded with maize (Zea mays L.), at two spacing measures (0.90 m and 0.45 m). The results indicate that the demand for power, tensile stress, and motor rotation, in the sowing operation, were not influenced by tillage and maize crop. The tractor wheel slip showed different results, being lower in no-tillage and higher in conventional and reduced tillage.

Fontes e parcelamento do nitrogênio em cobertura, na cultura do milho sob plantio direto

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da antecipação da adubação nitrogenada na cultura do milho em sistema plantio direto

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desempenho de fungicidas no controle da mancha-de-macrospora na cultura do milho

Fungicide application is one of the control strategies of fungal diseases in corn leaves. In Brazil, there are no fungicides recorded for the control of corn macrospora leaf spot (MLS). The aim of this study was to assess the efficacy of 16 fungicides on MLS control in a protective, curative and eradicant form. Fungicides of the chemical groups of benzimidazoles, strobilurins and triazoles were used alone or in mixture, in completely randomized block design, with six replicates of five plants, totaling 30 plants per treatment. The experiments were carried out in a greenhouse with the single-cross hybrid AS 1565 in phenological stage of two to six expanded leaves, using an isolate of S. macrospsora from the same hybrid. The inoculum was deposited into the cartridge of plants at 48 hours after, 48 hours before and 10 days before fungicide applications for preventive, curative and eradicant action, respectively. The experiment was repeated twice. The data underwent analysis of variance (p<0.05), and the means of treatments were compared by using the Scott-Knott test (p<0.05). Severity was estimated at 21 days after inoculations. All fungicides significantly differed from the control treatment in the preventive, curative and eradicant action. For the preventive action, mean disease control was 85%. The mixture of triazoles plus strobilurins controlled, on average, 75% of the disease severity, while the isolated products such as strobilurins reduced it by 62%, benzimidazoles by 55% and triazoles by 38% for the curative action. The lowest control was obtained for the eradicant action, with mean reduction of 40.1% in the disease severity and no significant difference among fungicides.

Gesso de minério associado a fontes de fósforo na cultura do milho em sistema plantio direto no Estado de Alagoas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Manejo do nitrogênio em cobertura na cultura do milho (Zea mays L.) em solo arenoso baseado no índice relativo de clorofila

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Épocas de adubação nitrogenada na cultura do milho e sua influência na cultura subsequente, girassol, em sistema de semeadura direta

Pós-graduação em Agronomia (Agricultura) - FCA

Períodos de interferência de uma comunidade infestante na cultura do milho em primeira e segunda safras

Pós-graduação em Agronomia (Agricultura) - FCA

Doses, épocas e modos de aplicação da uréia comum e revestida na cultura do milho

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Propriedades químicas de um latossolo tratado com lodo de esgoto e efeitos na cultura do milho

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Plantas de cobertura em pré-safra e aplicação de nitrogênio na cultura do milho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Adubação nitrogenada da cultura do milho consorciada com plantas de cobertura no sistema de semeadura direta

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Desempenho operacional de semeadora-adubadora de precisão em função do tipo de martelete e velocidade de deslocamento na cultura do milho

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Adubação de pré-semeadura na cultura do milho em diferentes manejo do solo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)