Portal de Periódicos da CAPES

Artigo Acesso aberto Produção Nacional Revisado por pares

BIBTEX RIS

Thermal time in sprinkler-irrigated lowland rice

2017; Embrapa Informação Tecnológica; Volume: 52; Issue: 7 Linguagem: Inglês

10.1590/s0100-204x2017000700001

1678-3921

Alex Cristiano Bartz, Martina Muttoni, Cleber Maus Alberto, Nereu Augusto Streck, Géter Alves Machado, Robson Giacomeli, Diogo Balbé Helgueira, Diogo da Silva Moura,

Rice Cultivation and Yield Improvement

Abstract: The objective of this work was to evaluate methods of thermal time calculation and the duration of the development stages of lowland rice (Oryza sativa) irrigated by sprinkling. The experiment was conducted during three growing seasons (2010/2011, 2011/2012, and 2014/2015), with five irrigation water depths, six cultivars, and four replicates. Six methods of thermal time calculation were tested: two using the minimum basal temperature; two using the minimum and optimum temperatures; and two using the minimum, optimum, and maximum basal temperatures. For the thermal time calculation, the crop development cycle was divided into the vegetative, reproductive, and grain-filling phases. The methods that used the three cardinal temperatures showed the lowest coefficients of variation for most of the developmental phases. Both irrigation water depths and rice cultivars affected the thermal time of the development stages. The greater the water availability, the lower the duration of the development cycle. Thermal time values depend on the calculation method.