Scientia Agrícola

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Agroforestry systems, nutrients in litter and microbial activity in soils cultivated with coffee at high altitude
(Escola Superior de Agricultura "Luiz de Queiroz", 2014-03) Notaro, Krystal de Alcantara; Medeiros, Erika Valente de; Duda, Gustavo Pereira; Silva, Aline Oliveira; Moura, Patrícia Maia de
Agroforestry systems are an alternative option for sustainable production manage- ment. These systems contain trees that absorb nutrients from deeper layers of the soil and leaf litter that help improve the soil quality of the rough terrain in high altitude areas, which are areas extremely susceptible to environmental degradation. The aim of this study was to characterize the stock and nutrients in litter, soil activity and the population of microorganisms in coffee (Cof- fea arabica L.) plantations under high altitude agroforestry systems in the semi-arid region of the state of Pernambuco, Brazil. Samples were collected from the surface litter together with soil samples taken at two depths (0-10 and 10-20 cm) from areas each subject to one of the follow- ing four treatments: agroforestry system (AS), native forest (NF), biodynamic system (BS) and coffee control (CT).The coffee plantation had been abandoned for nearly 15 years and, although there had been no management or harvesting, still contained productive coffee plants. The ac- cumulation of litter and mean nutrient content of the litter, the soil nutrient content, microbial biomass carbon, total carbon, total nitrogen, C/N ratio, basal respiration, microbial quotient, metabolic quotient and microbial populations (total bacteria, fluorescent bacteria group, total fungi and Trichoderma spp.) were all analyzed. The systems that were exposed to human inter- vention (AS and BS) differed in their chemical attributes and contained higher levels of nutrients when compared to NF and CT. BS for coffee production at high altitude can be used as a sustain- able alternative in the high altitude zones of the semi-arid region in Brazil, which is an area that is highly susceptible to environmental degradation.
Vegetative and productive aspects of organically grown coffee cultivars under shaded and unshaded systems
(Escola Superior de Agricultura "Luiz de Queiroz", 2011-07) Ricci, Marta dos Santos Freire; Rouws, Janaina Ribeiro Costa; Oliveira, Nelson Geraldo de; Rodrigues, Marinete Bezerra
Although Coffea arabica species has its origin in the African understories, there is great resistance on the part of the Brazilian producers for growing this species under agroforestry systems as they fear that shading reduces production. This study aimed at evaluating some vegetative traits and the productivity of organically grown coffee (Coffea arabica L.) cultivars under shaded and unshaded systems. Twelve treatments consisting of two cultivation systems (shaded and unshaded) and six coffee cultivars were arranged in randomized blocks with four replicates, in a split-plot scheme. Shading was provided by banana (Musa sp.) and coral bean plants (Erythrina verna). Shading delayed fruit maturation. Late maturation cultivars, such as the Icatu and the Obatã, matured early in both cultivation systems, while medium and early maturation cultivars presented late maturation. Cultivation in the shaded system increased the leaf area and the number of lower branches, decreased the number of productive nodes per branch, and increased the distance between the nodes and the number of leaves present in the branches. Cultivation in the unshaded system presented greater number of plants with branch blight in relation to plants grown in the shade. The productivity of the cultivars was not different, at 30.0 processed bags per hectare in the shaded system, and 25.8 processed bags per hectare in the unshaded system. The most productive cultivars in the shaded system were the Tupi, the Obatã, and the Catuaí, while no differences between cultivars were obtained in the unshaded system.
Growth rate and nutritional status of an organic coffee cropping system
(Escola Superior de Agricultura "Luiz de Queiroz", 2005-03) Ricci, Marta dos Santos Freire; Alves, Bruno José Rodrigues; Miranda, Simone Cordeiro de; Oliveira, Fabio Freire de
In view of the low N concentration in organic fertilizers, it is necessary to use high rates of such fertilizers to attend coffee crop requirements. Hence, N is the most limiting nutrient for organic coffee production. The objective of this work was to evaluate the influence of sunn hemp (Crotalaria juncea) organic fertilization on the growth and nutritional status of coffee cultivars, as well as to quantify plant biomass and N input derived from biological nitrogen fixation, and their effect on soil chemical characteristics. The experiment consisted of six coffee (Coffea arabica) cultivars intercropped with and without sunn hemp sown in November 2001 and pruned at mid-height 76 days later. At 175 days, the standing biomass of the legume was cut, measuring dry mass, total N, P, K, Ca, Mg, and 15 N natural abundance, resulting 16 t ha -1 of dry mass and the recycling of 444, 21, 241, 191, and 44 kg ha -1 of N, P, K, Ca, and Mg, respectively. Cultivars ‘Obatã’ and ‘Catuaí Vermelho’ presented the highest growth rates in terms of plant height, while cultivars ‘Icatu’ and ‘Oeiras’ presented the lowest rates. Biological nitrogen fixation associated to the legume introduced more than 200 kg ha -1 of N, which is a demonstration that N fertilization in organic cropping systems is a valuable alternative. Intercropping lead to a constant coffee leaf N content during the entire cropping cycle, contrary to what was observed in plots grown without sunn hemp.

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