Acta Scientiarum Agronomy
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/11111
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Item Productivity and grain size of coffee grown in different weed management systems(Editora da Universidade Estadual de Maringá - EDUEM, 2022-08-15) Zaidan, Úrsula Ramos; Campos, Renata Cássia; Faria, Rodrigo Magalhães; Zaidan, Iasmine Ramos; Souza, Wendel Magno de; Santos, Ricardo Henrique Silva; Freitas, Francisco Cláudio Lopes deIntensive weed management is one of the most common practices in coffee cultivation areas. Consequently, some problems, such as soil degradation and the selection of herbicide resistant weed, have increased over time, but, if properly managed, weeds at coffee planting inter-rows can offer benefits of erosion control, nutrient recycling and crop sustainability. The aim of this study is to evaluate the effect of different weed management strategies on the productivity and coffee grain size, i.e., quality. The experiment is installed onto a resprouting Coffea arabica L. site, four years after it was established. Treatments are implanted at planting inter-row Urochloa ruziziensis, Pueraria phaseoloides, and spontaneous vegetation maintained by mowing, herbicides, and weeding. To measure dry matter accumulation, samples are taken with a 0.25 m2 square template at plots maintained by mowing and herbicide application. To evaluate the yield and granulometry, coffee fruits are harvested, processed and classified in a set of 14 sieves (grouped in flat or “moca” shapes). The methods of controlling herbicide and weeding show significance in relation to grain production, with the production of grains having a higher market value standing out, when compared with the other treatments. The accumulation of dry matter above soil, in treatments with herbicides and spontaneous vegetation positively influenced the early coffee productivity (2018), and with U. ruziziensis and spontaneous vegetation, positively influenced the productivity of late harvest (2019). The accumulation of dry matter on the soil tends to be positively linked to coffee productivity, especially in periods when there is a shortage of rain in the region under study; however, it cannot be stated that this influence relationship (causality) has a direct positive effect between dry matter mass production and productivity of future coffee plantations.Item Desenvolvimento de Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) em cafeeiros(Editora da Universidade Estadual de Maringá - EDUEM, 2009-01) Santa-Cecília, Lenira Viana Costa; Correa, Lílian Roberta Batista; Souza, Brígida; Prado, Ernesto; Alcantra, ElianaA cochonilha Planococcus citri (Risso, 1813) suga a seiva dos botões florais e frutos do cafeeiro, atacando as rosetas desde a floração até a colheita. Embora seja relatada há alguns anos na cafeicultura, são escassas as informações sobre o desenvolvimento dessa cochonilha em cafeeiros. Assim, o presente trabalho teve por objetivos avaliar alguns aspectos biológicos da fase ninfal de P. citri em plantas de café. Ovos dessa cochonilha foram retirados de uma criação em laboratório, isolados em placas de Petri contendo discos foliares de Coffea arabica L., das cultivares Acaiá Cerrado, Mundo Novo e Catuaí Vermelho e de C. canephora Pierre & Froenher, cultivar Apoatã. As placas foram mantidas em câmara climatizada a 25 ± 1°C, 70 ± 10% de umidade relativa e 12h de fotofase. Constatou-se que a cultivar Catuaí Vermelho foi a que proporcionou maior duração do período ninfal das fêmeas, porém, não foram constatadas diferenças na mortalidade. Essa cochonilha se desenvolveu satisfatoriamente em todas as cultivares de café estudadas e os resultados não mostraram diferenças claras de susceptibilidade.Item Photosynthetic activity of coffee after application of glyphosate subdoses(Editora da Universidade Estadual de Maringá - EDUEM, 2013-01) Carvalho, Felipe Paolinelli de; França, André Cabral; Lemos, Vinícius Teixeira; Ferreira, Evander Alves; Santos, José Barbosa dos; Silva, Antonio Alberto daFarmers use non-selective herbicides, such as glyphosate, in directed applications to control weeds in coffee crops. Despite the precautions used during the application of herbicides, there are usually reports of poisoning in plantation areas. Moreover, it is fundamental to understand the effects of glyphosate on photosynthetic processes. The present study aimed to evaluate the characteristics associated with the photosynthetic activity in coffee cultivars subjected to doses of glyphosate. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), including Acaiá (MG-6851), Catucaí Amarelo (2 SL) and Topázio (MG-1190), and three subdoses of glyphosate (0.0, 115.2 and 460.8 g ha -1 ) in a 3 x 3 factorial scheme. Herbicide application led to reduced internal carbon, ratio between internal and environmental carbon, carbon consumption and photosynthetic rate at 15 days after application (DAA) in the fourth leaf. In the same leaf at 45 DAA, the carbon consumption of the cultivars was even less. Despite low carbon concentrations, no difference in consumption and photosynthetic rate was observed in the last leaf. Glyphosate caused metabolic damage with transitory effects on the photosynthetic rate; the Acaiá cultivar was the most tolerant. These transitory effects may result in irreversible and prolonged damage to crop growth.Item Control of coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae) with botanical insecticides and mineral oils(Editora da Universidade Estadual de Maringá - EDUEM, 2016-01) Celestino, Flávio Neves; Pratissoli, Dirceu; Machado, Lorena Contarini; Santos Junior, Hugo José Gonçalves dos; Queiroz, Vagner Tebaldi de; Mardgan, LeonardoThe objective of this study was to evaluate botanical oils, mineral oils and an insecticide that contained azadirachtin (ICA) for the control of Hypothenemus hampei, in addition to the effects of residual castor oil. We evaluated the effectiveness of the vegetable oils of canola, sunflower, corn, soybean and castor, two mineral oils (assist ® and naturol ® ), and the ICA for the control of H. hampei. The compounds were tested at a concentration of 3.0% (v v-1 ). The median lethal concentration (LC 50 ) was estimated with Probit analysis. The oil of castor bean and extract of castor bean cake were also evaluated at concentrations of 3.0% (v v -1 ) and 3.0% (m v-1 ), respectively. The mortality rates for H. hampei caused by the ICA and the castor oil were 40.8 and 53.7%, with LC 50 values of 6.71 and 3.49% (v v-1 ), respectively. In the castor oil, the methyl esters of the fatty acids were palmitic (1.10%), linoleic (4.50%), oleic (4.02%), stearic (0.50%) and ricinoleic acids (88.04%). The extract of the castor bean cake was not toxic to H. hampei. The persistence of the castor oil in the environment was low, and the cause of mortality for H. hampei was most likely the blockage of the spiracles, which prevented the insects from breathing.