Determinação do coeficiente de cultura da melancia, em solo sob palhada e preparo convencional, na microrregião de Teresina, Piauí

• Ano de defesa: 2012
• Autor(a) principal: Silva, Eduardo Magno Pereira da
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Engenharia agrícola; Citrullus lanatus; Lisímetro; Evapotranspiração; Kc
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/18585

The experiment was carried out at in Teresina county (5 ° 05'S, 42 ° 29'W and 72 m altitude), an area of 1.2 ha in the period from September to November 2011, in ofder determine the watermelon (Citrullus lanatus L.) crop coefficient, hybrid Olympia, drip irrigated, cultivated in soil under conventional tillage and straw, at soil and climate conditions of the Teresina region, Piauí State, Brazil. The soil of the experimental area is classified as an Oxisol, sandy loam texture. The climate, according to Köeppen classification is Aw ', hot and humid tropical, with summer rainy season. To order the formation of straw ground cover was planted in half of the experimental area, pearl millet (Pennisetum glaucum L.). The crop evapotranspiration (ETc) was determined daily using the average of three weighing lysimeters, with 2.25 m2 surface area, measured in each condition (mulch and conventional tillage), occured between 6 to 18 hours. The experimental was design a completely randomized. The reference evapotranspiration (ETo) was estimated by the FAO-Penman-Monteith, with daily records of air temperature, air relative humidity, solar radiation and wind speed obtained from weather station installed at 500 m from the experimental area. The total ETc observed during the watermelon cycle in straw and conventional tillage was 206.78 and 222.26 mm, respectively. The values of Kc in the straw were 0.23, 0.52, 1.28 and 0.56 and conventional tillage were 0.27, 0.57, 1.36 and 0.61, for initial (sowing to 18 days after sowing - DAS), vegetative growth (from 19 to 32 DAS), intermediate (from 33 to 51 DAS) and late (from 52 to 64 DAS), respectively. The crop water requirement under straw was 7.5% lower than measured under conventional tillage.