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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item A diversificação da vegetação reduz o ataque do bicho-mineiro-do-cafeeiro Leucoptera coffeella (Guérin-mèneville) (Lepidoptera: Lyonetiidae)?(Sociedade Entomológica do Brasil, 2010-09-14) Amaral, Dany S .; Venzon, Madelaine; Pallini, Angelo; Lima, Paulo C.; Souza, Og deThe effects of increasing plant diversity on the population of the coffee leaf-miner Leucoptera coffeella (Guérin-Mèneville) were investigated in two organic coffee production systems. One system consisted of coffee intercropped with banana trees (shaded system) and the other one of coffee intercropped with pigeon pea (unshaded system). The increase in plant diversity on both systems was achieved via introduction of green manures such a perennial pea nut, sunn hemp and Brazilian lucerne. The population of L. coffeella, predation and parasitism of L. coffeella mines were biweekly evaluated during eight months. The increase in plant diversity on both systems did not affect the attack of L. coffeella on coffee leaves and the mine parasitism rate. However, there was a positive and significant relationship between increasing plant diversity and coffee leaf mine predation by wasps on unshaded coffee system and a negative relationship on shaded coffee system.Item Diet, microhabitat use, and thermal preferences of Ptychoglossus bicolor (Squamata: Gymnophthalmidae) in an organic coffee shade plantation in Colombia(Museu de Zoologia da Universidade de São Paulo, 2010) Anaya-Rojas, Jaime M.; Serrano-Cardozo, Víctor H.; Ramírez-Pinilla, Martha P.Ptychoglossus bicolor is a small gymnophthalmid lizard distributed in the Magdalena Valley of Colombia. We studied ecological features of diet, microhabitat use, and thermal preferences of a population found in an organic coffee shade plantation at the Cordillera Oriental of the Colombian Andes. The studied population had a diet composed predominantly of isopods. The Relative Importance Index of isopods was 98.8%; there were no significant monthly differences in the full stomach content and volume of isopods eaten during the sampling year, neither between rainy and dry seasons. A large number of lizards were found active in the leaf-litter, buried around coffee tree roots, and under or in rotting logs. Lizard body temperature was positively correlated with substrate temperature and air temperature; sex differences in body temperature were not significant. At the studied locality we did not find lizards out of the coffee fields. Our results suggested that these lizards successfully cope with the conditions offered by the organic coffee areas as a result of the cultivation system. Thus, this population might be vulnerable to any modification of the habitat that changes microhabitat availability and abundance of isopods.Item Alternative treatments diminish oviposition and viability of Leucoptera coffeella (Lepidoptera: Lyonetiidae) eggs and larvae on coffee plants(Editora UFLA, 2021) Androcioli, Humberto Godoy; Hoshino, Adriano Thibes; Meneghin, Ana Maria; Ventura, Mauricio Ursi; Guide, Bruna Aparecida; Hata, Fernando Teruhiko; Menezes Junior, Ayres de OliveiraThe effects of alternative treatments on the oviposition and viability of Leucoptera coffeella eggs and larvae were evaluated. Under controlled conditions, coffee sprouts cv. IAPAR-59, eight months old, were sprayed with brown propolis extract (1%), pyroligneous extract with pepper and garlic (PEPG) (2%), silicate clay (2%), kaolin (5%), lime sulfur (2%), neem oil (1%) and kaolin + neem oil (5% + 1%), distilled water and no treatment. In a first no-choice bioassay, coffee sprouts were sprayed before oviposition and kept in cages, where adult insects within three days after emergence were released. Adults remained in the cages for 24 hours. Eggs were then counted. 10 eggs per sprout were preserved to verify larval mortality. The number of eggs when treated with propolis extract, neem oil, kaolin + neem oil and PEPG decreased in the evaluations. Treatments with neem oil caused greater larval hindrance. Eggs laid on leaves were also sprayed with the treatments. Egg viability was reduced by treatments containing neem oil and lime sulfur. Neem oil treatments resulted in slim adult emergence; intermediate viability with lime sulfur and slight hindrance with silicate clay. Finally, treatments were also sprayed on leaves, hosting first or third instar larvae. Neem treatment caused high mortality for 1st and 3rd instar larvae, however, this effect was reduced when mixed with kaolin. Nonetheless, these negative effects disappeared when considering the adult survival ratio. Results indicated that propolis extract, PEPG and neem oil treatments are suitable for reducing egg deposition, neem oil considerably diminished larvae survival and adult emergence.Item Comparative study of metal contents in Brazilian coffees cultivated by conventional and organic agriculture applying principal component analysis(Sociedade Brasileira de Química, 2010) Santos, José S. dos; Santos, Maria Lúcia P. dos; Conti, Melina M.The aim of this study was to evaluate of availability of nutrients and toxic elements in green coffees produced in traditional, technological and transitional organic farms in Southwest BahiaBrazil. Levels of the nutrients minerals were determined directly in samples of soils and coffee tissues from four farms by flame atomic absorption spectrometry (FAAS) and toxic elements (Cr, Ni, Cd and Pb) by inductively coupled plasma optical emission spectrometry (ICP OES). The application of statistical methods (cluster and principal components analysis) revealed the importance of the conversion period to guarantee a product genuinely organic during the change to organic agriculture. On the other hand, the study of correlations between agricultural methods and metals concentrations in coffee suggested that Cd, Cu, Zn and other toxic elements contained in some inorganic fertilizers used in the traditional and technological coffee farms may cause na increase of toxic metals concentration in the crop soil, be taken up by plants, and passed on in the food chain.Item Decomposition and nutrients released from forest and perennial crops associated with organic coffee(Editora UFLA, 2021) Araujo, João Batista Silva; Silva, Matheus Wandermurem da; Lima, Wallace Luís de; Pereira, Ana Claudia Hertel; Endringer, Denise Coutinho; Souza, Jacimar Luís deAgroforestry consortia increase organic matter and nutrient cycling in agricultural systems. For this reason, the objective of this work was to study the release rate of nutrients and the decomposition of different organic residues, two times of the year, obtained from four cultures intercropped with conilon coffee, aiming to relate the released nutrients to the coffee needs. The decomposition of organic matter residues and the release of nutrients from Inga edulis, Musa spp, Gliricidia sepium, and Bactris gasipaes were evaluated in two different periods. I. edulis residues with a higher amount of polyphenols, and those of Musa spp, with a higher C/N ratio, showed slow decomposition. The decomposition rates were lower in experiments started in March and higher in August. Inga and banana have high residual values of nutrients at 270 days in the decomposition started in March.Item 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 BezerraAlthough 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.