Periódicos

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 2 de 2
  • Imagem de Miniatura
    Item
    Soil enzymatic activity under coffee cultivation with different water regimes associated to liming and intercropped brachiaria
    (Universidade Federal de Santa Maria, 2022) Rodrigues, Raquel Nogueira; Reis Junior, Fábio Bueno dos; Lopes, André Alves de Castro; Rocha, Omar Cruz; Guerra, Antônio Fernando; Veiga, Adriano Delly; Mendes, Ieda de Carvalho
    This research evaluated the effects of coffee cultivation with two different water regimes associated or not with liming and the presence/absence of brachiaria as intercrop on the activities of the soil enzymes β-glucosidase, arylsulfatase and acid phosphatase. The study was carried out at the experimental farm of Embrapa Cerrados, using the cultivar IAC 144 (Coffea arabica L.), under a clayey dystrophic Cerrado Oxisol. Two water regimes (WR) were considered, WR1 with irrigation shifts throughout the year and WR3 with controlled water stress, for about 70 days, in the dry season. In each water regime, effects of lime application (with/without) and the presence/absence of brachiaria cultivated between the lines of coffee plants were evaluated. The activities of the enzymes β-glucosidase, arylsulfatase and acid phosphatase were evaluated during the rainy and dry seasons. Liming and intercropped brachiaria positively affected the activities of the three enzymes assessed in this study at varying degrees, depending on season and/or the WR. Our findings evidenced that intercropped brachiaria in coffee rows was the factor that most positively impacted soil enzymes activ ities.
  • Imagem de Miniatura
    Item
    Microbiological properties and oxidizable organic carbon fractions of an oxisol under coffee with split phosphorus applications and irrigation
    (Sociedade Brasileira de Ciência do Solo, 2013-01) Costa, Adriana Rodolfo da; Sato, Juliana Hiromi; Ramos, Maria Lucrécia Gerosa; Figueiredo, Cícero Célio de; Souza, Géssica Pereira de; Rocha, Omar Cruz; Guerra, Antônio Fernando
    Phosphorus fertilization and irrigation increase coffee production, but little is known about the effect of these practices on soil organic matter and soil microbiota in the Cerrado. The objective of this study was to evaluate the microbiological and oxidizable organic carbon fractions of a dystrophic Red Latossol under coffee and split phosphorus (P) applications and different irrigation regimes. The experiment was arranged in a randomized block design in a 3 x 2 factorial design with three split P applications (P1: 300 kg ha -1 P 2 O 5 , recommended for the crop year, of which two thirds were applied in September and the third part in December; P2: 600 kg ha -1 P 2 O 5 , applied at planting and then every two years, and P3: 1,800 kg ha -1 P 2 O 5 , the requirement for six years, applied at once at planting), two irrigation regimes (rainfed and year-round irrigation), with three replications. The layers 0-5 and 5-10 cm were sampled to determine microbial biomass carbon (MBC), basal respiration (BR), enzyme activity of acid phosphatase, the oxidizable organic carbon fractions (F1, F2, F3, and F4), and total organic carbon (TOC). The irrigation regimes increased the levels of MBC, microbial activity and acid phosphatase, TOC and oxidizable fractions of soil organic matter under coffee. In general, the form of dividing P had little influence on the soil microbial properties and OC. Only P3 under irrigation increased the levels of MBC and acid phosphatase activity.