Rocha R.S.,Producao Vegetal |
Da Silva J.A.L.,CCA UFPI |
Neves J.A.,Producao Vegetal |
Sediyama T.,Federal University of Viçosa |
Teixeira R.C.,Federal University of Viçosa
Revista Ciencia Agronomica | Year: 2012
This study had as its objective to evaluate the agronomic performance of soybean varieties and strains grown under low-latitude conditions in Teresina, PI. Phenological traits, yield, and characteristics related to the development of soybean plants from 32 genotypes taken from pre-launch strains and varieties were evaluated, some already launched in states in the midwest region of Brazil. The experimental design used was of randomized blocks with four replications. Under the conditions studied, 13 genotypes (nine varieties and four strains) were identified as having good agronomic performance in low latitudes, with an average grain yield of over 2,900kg ha-1 (48.3 sacks of 60kg ha-1). Of those genotypes studied, based on certification of BRS Sambaíba and Msoy 9350, those that stood out most for the traits assessed and for satisfactory mechanical harvesting under low-latitude conditions, were the Conquista and Valiosa RR varieties and the strains BCR892 G132, BCR651 G75 and BCR6651 G68.
de Alcantara Neto F.,CPCE UFPI |
de Amaral Gravina G.,Laboratorio Of Engineering Agricola |
Souza N.O.S.,University of Brasilia |
de Carvalho Bezerra A.A.,CCA UFPI
Revista Ciencia Agronomica | Year: 2010
The objective of this work was to evaluate some biometric characteristics and the soybean grain yield, cultivated in a soil with low content of phosphorus and submitted to different rates of phosphorus fertilization. The experiment was located in Gilbués-PI, South of the Piauí state, from December 2007 until April 2008, in an Oxisoil. The experiment followed a randomized blocks design, with the treatments arranged as six doses of phosphorus (0; 40; 60; 100; 120 and 140 kg ha-1 of P2O5) with four replications. It was evaluated the height of plants, height of first pod insertion and the grain yield. The levels of P had influenced as a quadratic response the height of the plants, being the maximum height estimated as 56.69 cm for the quantity of 95.60 kg ha-1 of P2O5. The height of insertion of the first soybean pod was had not influenced by the P fertilization and had a mean estimated as 10.64 cm. A quadratic response of the grains productivity to the rates of P was observed, being the maximum productivity estimated as 2.614.7 kg of grains of soybean for 94.8 kg ha-1 of P2O5.
Leite L.F.C.,Embrapa Meio norte |
Arruda F.P.,CCA UESPI |
Costa C.N.,CCA UFPI |
Ferreira J.S.,Federal Rural University of Pernambuco |
Holanda Neto M.R.,UESPI
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2013
This study aimed to evaluate the effects of the cultivation of acrocomia palm (Acrocomia aculeata) intercropped or not with pasture on the chemical quality and carbon pools of an Oxisol of the Savanna of Maranhão state. Four land use systems were studied: acrocomia, pasture, acrocomia intercropped with pasture and savanna native vegetation. Soil samples were collected up to 60 cm depth for determination of chemical attributes and soil organic carbon contents and stocks. The highest values of P, K, Ca and Mg were observed in the soil under pasture. Total organic carbon stocks and labile carbon content were higher under native vegetation up to 60 cm followed by acrocomia intercropped with pasture system. Higher values of microbial biomass carbon and microbial quotient were verified in the soil under pasture in all depths. Pasture is important to be intercropped with acrocomia since it increases the soil fertility levels and soil carbon stocks favoring the improvement of the soil quality in the Savanna of Maranhão state.
de Oliveira S.R.M.,Colegio Tecnico de Teresina |
de Andrade Junior A.S.,Embrapa Meio Norte |
Ribeiro V.Q.,Embrapa Meio Norte |
de Brito R.R.,São Paulo State University |
Carvalho M.W.,CCA UFPI
IRRIGA | Year: 2015
The objective of this study was to evaluate the effect of levels of water, plant density and their interaction on growth (dry matter and leaf area) and yield of cowpea (Vigna unguiculata L. Walp.). The experiment was carried out at the experimental area of Middle- North Embrapa in Teresina city, Piauí-Brazil from July to September 2012 in a Ultisol soil. A randomized block experimental design was used with four replicates. Treatments were applied in a 5 x 4 factorial design and 5 levels of irrigation as factors: 393.53; 340.34; 300.50; 260.39 and 201.73 mm applied through an irrigation system by conventional sprinkler, and four plant densities: 150,000; 200,000; 250,000; 300,000 plants ha-1. A significant interaction between irrigation levels and plant density was found in all study parameters except for dry matter. Leaf area, grain yield, number of pods per plant, pod weight, pod yield, pod length and hundred grain weight had maximum values of 1,301.89 cm2; 1,668.86 kg ha-1; 2.24; 2,248.16 kg; 1,873.45 kg ha-1; 18.70 cm and 22.72 g, which were reached using the following water depths: 367.86; 390.88; 393.53; 393.53; 393.53; 348.40 and 322.63 mm associated with densities of : 188,000; 241,000; 110,000; 254,000; 254,000; 223,000 and 300,000 plants.ha-1, respectively. © 2015, Universidade Estadual Paulista - UNESP. All rights Reserved.