Slaughterhouses generate large amounts of rumen content and its use as a fertilizer may offer an environmentally friendly strategy for its management. The effect of an organic fertilizer produced from slaughterhouse waste on the fertility of sandy and clayey soils as well as soybean yield (Glycine max L.) and corn (Zea mays L.) crops was evaluated. Field experiments were set up and five rates up to 16 t ha−1 of organic fertilizer (293 kg ha−1 N, 334 kg ha−1 P and 27 kg ha−1 K) were applied annually, before sowing in spring/summer, as well as a mineral fertilization of 300 kg ha−1 in the formulation 2-20-20 for soybean and 300 kg ha−1 of 12-15-15 for corn. The organic fertilizer changed soil fertility in the field experiments by increasing pH, Ca, Mg, K, P-Mehlich and P-resin. Such effects were more evident in the sandy than in the clayey soil, and the most superficial layer was affected more. The organic fertilizer rate needed to achieve maximum yield decreased for corn in both soils and for soybean in the sandy soil, although the amounts required may still be regarded as high.

The objective of this study was to measure ammonia volatilization from surface application of pig slurry, poultry litter, urea and no fertilization. An experiment was conducted in a randomized block design, in plots repeated over time, with four treatments and four replications. The fertilizers tested were: mineral fertilizer (70 kg ha-1 N, 100 kg ha-1 P2O5 and 30 kg ha-1 of K2O, as urea, triple superphosphate and potassium chloride, respectively), pig slurry (200 m³ ha-1 applied in November 2008 and 200 m³ ha-1 applied in April 2009) and poultry litter (10 t ha-1 applied in November 2008 and 10 t ha-1 applied in April 2009). Five evaluations were performed with 24-hour intervals. Foams were used with glycerin and sulfuric acid, internally fixed in PET bottles for collecting ammonia. After collected, the samples were sent to the laboratory to determine volatilized ammonia levels by the semi-micro Kjedahl distillation method. Fertilization with chicken litter had lower ammonia volatilization in relation to urea and pig slurry. Most of the ammonia volatilization from pig slurry occurred within 48 hours after application, totaling losses of 630 g kg-1 of a total of 8.25 kg ha-1 of volatilized ammonia. The biggest loss by ammonia volatilization was from fertilization with urea, totaling approximately 80 g kg-1 of N applied.

Foram avaliados os efeitos do tratamento da cama de frango sobre o teor de umidade, o pH, a densidade e a amônia volatilizada durante cinco lotes consecutivos de criação de frangos de corte. Foram utilizadas 640 aves por lote em delineamento inteiramente casualizado com oito tratamentos e quatro repetições. Os tratamentos foram: 1 cama não-tratada; 2 cama submetida à compostagem dentro do galpão; 3 cama tratada com sulfato de alumínio; 4 cama tratada com gesso agrícola; 5 cama tratada com cal virgem; 6 cama tratada com calcário dolomítico; 7 cama tratada com zeolita; e 8 cama tratada com carvão vegetal. O feno de capim-elefante picado foi utilizado como cama de frango em todos os lotes. A fermentação no galpão aumentou o teor de umidade das camas no segundo e primeiro lotes aos 21 e 42 dias de criação, respectivamente. Não houve diferença na densidade entre os tratamentos. O sulfato de alumínio reduziu o pH das camas em todos os lotes aos 21 dias de criação. Aos 42 dias, o pH das camas foi reduzido nas camas contendo sulfato de alumínio e gesso agrícola no primeiro, segundo e quarto lotes. Aos 21 dias, o sulfato de alumínio reduziu a amônia volatilizada no primeiro, terceiro e quarto lotes e, aos 42 dias, houve redução da amônia volatilizada das camas contendo sulfato de alumínio no quarto lote. O sulfato de alumínio pode melhorar a qualidade da cama de frango de feno de capim-elefante picado, por reduzir o pH e a volatilização de amônia.

It was evaluated the effects of poultry litter treatment on moisture content, pH, density and volatilized ammonia for five consecutive flocks of broiler chicken breeding. It was used 640 birds per flock as a complete randomized design with eight treatments and four replicates. The treatments were the following: 1 non-treated litter; 2 litter submitted to in-house composting; 3 litter treated with aluminum sulfate; 4 litter submitted to gypsum; 5 litter treated with quicklime; 6 litter treated with dolomitic limestone; 7 litter treated with zeolite and 8 litter treated with charcoal. Chopped elephant-grass hay was used as poultry litter in all flocks. Fermentation in the shed increased moisture content of the litters in the second and first flocks on 21 and 42 days of breeding, respectively. There was no difference on density among treatments. Aluminum sulfate reduced pH of the litters in all flocks at 21 days of breding. On 42 days of breeding, pH of the litters was reduced in the litters with aluminum sulfate and gypsum in the first, second and forth flocks. On 21 days, aluminum sulfate reduced the volatilized ammonia in the first, third and forth flocks, and on 42 days, there was a reduction of volatilized ammonia in the litters with aluminum sulfate in the forth flock. Aluminum sulfate can improve quality of poultry litter of chopped elephant-grass hay by reducing pH and ammonia volatilization.

Atualmente, tem-se difundido a aplicação de inoculante no sulco de semeadura na cultura da soja, mas há poucas informações que dão suporte a essa prática e comprovam sua eficiência em diferentes ambientes manejados sob plantio direto. Este trabalho teve como objetivo avaliar a viabilidade da aplicação de inoculantes na cultura da soja, via semente e sulco de semeadura, em solo já cultivado ou não com soja. Foram realizados dois experimentos em campo a partir de dezembro de 2004 em Latossolo Vermelho-Amarelo, seguindo o mesmo método e tratamentos, porém em dois locais distintos, com ou sem cultivo anterior de soja. Foram testados oito tratamentos: (1) inoculação via semente (inoculante + fungicida + micronutriente); (2) sem inoculação (fungicida + micronutriente); (3) testemunha (semente pura, sem tratamento); (4) aplicação no sulco-dose 1 (dose do inoculante recomendada no sulco); (5) aplicação no sulco-dose 2 (duas vezes a dose recomendada no sulco); (6) aplicação no sulco-dose 3 (três vezes a dose recomendada no sulco); (7) sulco-dose 1 + inoculação via semente; e (8) adubação com N (200 kg ha-1 N). Foram avaliados massa de matéria seca de nódulos e número de nódulos totais e nódulos viáveis e não-viáveis aos 30 e 75 dias após emergência. A melhor nodulação foi obtida com aplicação de inoculante + fungicida + micronutriente via semente no solo ainda não cultivado. No solo previamente cultivado com soja, destacaram-se os tratamentos uma e duas vezes a dose do inoculante no sulco. Menores valores de massa seca de nódulos na soja foram obtidos no tratamento com adubação mineral. A aplicação via sulco do inoculante mostrou-se uma prática viável, em razão da semelhança dos resultados obtidos com a aplicação tradicional via semente.

Nowadays, inoculant application in the sowing furrow of soybean is widely used, but there is little information underlying this practice, which would prove the efficiency in different environments under no-tillage systems. This study aimed to evaluate the viability of inoculant application to soybean, via seed and in-furrow, in soil never cultivated with soybean or previously cultivated with soybean. Two field experiments were carried out as of December 2004 in a Red Yellow Latosol (Oxisol), using the same methodology and applying the same treatments, at two different sites, with or without previous soybean cultivation. Eight treatments were tested: (1) seed inoculation (inoculant + fungicide + micronutrient), (2) without inoculation (fungicide + micronutrient), (3) control (pure seed without treatment), (4) in-furrow application dose 1 (recommended dose of inoculant in the furrow), (5) in-furrow application dose 2 (the double of the recommended dose in the furrow), (6) furrow application dose 3 (three times the recommended dose in the furrow), (7) furrow-dose 1 + seed inoculation, and (8) N fertilization (200 kg ha-1 N). The dry matter mass of the nodules, the number of total nodules and viable and non-viable nodules were evaluated 30 and 75 days after emergence. The treatment inoculant + fungicide + micronutrient application via seed in the non-cultivated soil resulted in the best nodulation. In the soil previously cultivated with soybean, the treatments with the simple and double inoculant dose in the furrow reached the best results. Nodule dry mass was the lowest in the treatment with mineral fertilization. In-furrow application of the inoculant seemed a viable practice due to the similarity of the results with traditional seed inoculation.

Os objetivos deste trabalho foram definir as faixas críticas de concentração de nutrientes e avaliar o estado nutricional das lavouras cafeeiras de alta, média e baixa produtividade em quatro regiões do Estado de Minas Gerais. Foram coletadas folhas em 312 unidades amostrais de 168 lavouras, tanto no ano de alta produtividade quanto no de baixa produtividade, conforme o ciclo bienal do cafeeiro. Nas folhas foram determinadas as concentrações de macronutrientes e dos micronutrientes Cu, Fe, Zn, Mn e boro. Com os resultados das análises foliares, estabeleceram-se as faixas críticas das concentrações dos nutrientes no ano de baixa e alta produtividade, em cada região estudada, utilizando como referência lavouras de alta produtividade (mais de 1.800 kg/ha de café beneficiado na média do biênio). Realizou-se ainda o diagnóstico do estado nutricional das lavouras nas regiões em estudo determinando-se as freqüências de nutrientes em níveis deficiente, adequado e excessivo. As faixas críticas não diferiram entre os anos amostrados, tampouco entre as regiões em estudo. Nas regiões amostradas predominam problemas com micronutrientes.

The objectives of this work were to define the critical nutrients ranges and evaluating the nutritional state of coffee-tree plantations with low, intermediate and high productivities in four areas of the State of Minas Gerais. Leaves of 312 sample units of 168 farms were collected in two consecutive years, one of high productivity and another of low productivity, according to the biennial cycle of the coffee-tree. In the leaves all the macronutrients and the micronutrients Cu, Fe, Zn, Mn and B were analyzed. With the results of the analyses the critical ranges of the nutrients in the years of low and high productivity and for each studied area were calculated, using as reference farms of high productivity (more than 1,800 kg/ha of green coffee in the average of two consecutive years). The diagnosis of the nutritional state of the farms in the studying areas was made through the frequencies of nutrients in deficient, appropriate and excessive levels. The obtained critical ranges did not differ either between the sampled years or among the areas. In the studied area nutritional problems with micronutrients were predominant.