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Resultados da Pesquisa
Item Leaf miner incidence in coffee plants under different drip irrigation regimes and planting densities(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2012-02) Assis, Gleice Aparecida; Assis, Franscinely Aparecida; Scalco, Myriane Stella; Parolin, Francisco José Toloza; Fidelis, Iraci; Moraes, Jair Campos; Guimarães, Rubens JoséThe objective of this work was to evaluate the effect of different drip irrigation regimes and planting densities on the incidence of the leaf miner, Leucoptera coffeella, in arabica coffee plants for one year. The experiment was carried out in 2008, in a complete randomized block design, in a split‐plot in time arrangement, with four replicates. The treatments consisted of four drip irrigation regimes – soil water balance, irrigations at 20 and 60 kPa soil tensions, and a nonirrigated treatment –, which were distributed at three plant densities: 2,500, 5,000, and 10,000 plants per hectare. The evaluations were made on a monthly basis between January and December 2008. The highest pest occurrence period was from August to November, a season with low‐air relative humidity preceded by a drought period. Irrigated coffee plants showed an incidence of intact mines 2.2 times lower than that of nonirrigated plants. Irrigation and increasing of plant density contribute to the reduction of coffee leaf miner occurrence.Item Floração e potencial hídrico foliar de cafeeiros sob diferentes regimes hídricos e densidades de plantio(Editora UFLA, 2013-04) Castanheira, Dalyse Toledo; Scalco, Myriane Stella; Fidelis, Iraci; Assis, Gleice Aparecida; Pereira, Fábio Santos; Matos, Nagla Maria Sampaio deO estudo das relações hídricas do cafeeiro é de suma importância em todas as fases de desenvolvimento da cultura. Objetivou-se ,neste trabalho,avaliar, ao longo de dois anos, o potencial hídrico foliar na “antemanhã” e a produção média total de flores de cafeeiros não irrigados e irrigados sob diferentes regimes hídricos, em quatro densidades de plantio. Foi usada a cultivar Rubi MG-1192, plantada em janeiro de 2001, no delineamento experimental de blocos casualizados, em esquema de parcelas subdivididas com três repetições. Os tratamentos constaram de três regimes hídricos: (i) irrigação quando a tensão da água no solo atingiu valores próximos a 20 kPa e suspensão das irrigações nos meses de julho e agosto; (ii) irrigação quando a tensão da água no solo atingiu valores próximos a 60 kPa e suspensão das irrigações nos meses de julho e agosto (iii) uma testemunha não irrigada e quatro densidades de plantio de: (i) 2500 (4,0 x 1,0m), (ii) 3333 (3,0 x 1,0m); (iii) 5000 (2,0 x 1,0m) e (iv) 10000 plantas ha -1 (2,0 x 0,5m). O potencial hídrico foliar (Yf) “antemanhã” foi determinado utilizando-se uma câmara de pressão. Em 2009, os menores valores observados foram de -1,6 MPa em cafeeiros não irrigados e irrigados a 60 kPa na densidade de 2500 plantas ha -1 . Esses valores foram observados nos meses de setembro, outubro e novembro. No segundo ano, o valor de -1,5 MPa foi alcançado ao final do período de suspensão de irrigação (agosto) e ocorreu em plantios menos adensados. Em ambos os anos, em cafeeiros adensados o regime hídrico não afetou a produção média total de flores. Os valores de potencial hídrico foliar não se correlacionaram com a produção média total de flores.Item Flowering and leaf water potential in coffee under different water regimes and planting densities(Editora UFLA, 2013-04) Castanheira, Dalyse Toledo; Scalco, Myriane Stella; Fidelis, Iraci; Assis, Gleice Aparecida; Pereira, Fábio SantosThe study of water relations in coffee is of utmost importance at all stages of crop development. The aim of this study was to evaluate “pre-dawn” leaf water potential and the total average production of flowers in non-irrigated and irrigated coffee plants under different water regimes in four planting densities over a two-year period. The cultivar Rubi MG-1192 was used, planted in January 2001 in a randomized block experimental design in split-plots with three replications. Treatments consisted of three water regimes: (i) irrigation when soil water tension reached values around 20 kPa and suspension of irrigation during July and August; (ii) irrigation when soil water tension reached values around 60 kPa and suspension of irrigation during July and August and (iii) a non-irrigated control. Four planting densities were used: (i) 2500 (4.0 x 1.0 m), (ii) 3333 (3.0 x 1.0 m), (iii) 5000 (2.0 x 1.0 m) and (iv) 10000 plants ha-1 (2.0 x 0.5 m). The “pre-dawn” leaf water potential (Yf) was determined using a pressure chamber. In 2009, the lowest values observed were -1.6 MPa in non-irrigated and irrigated coffee at 60 kPa at a density of 2500 plants ha-1. These values were observed during September, October and November. In the second year, the value of -1.5 MPa was reached at the end of the period of suspension of irrigation (August) and occurred in less dense plantings. In both years, in dense coffee plantings, the water regime did not affect total average production of flowers. The values of leaf water potential did not correlate with the total average production of flowers.