DEMANDA HÍDRICA E CRESCIMENTO DO MELOEIRO EM RELAÇÃO AOS GRAUS-DIA ACUMULADO

Abstract

The melon culture has an expressive production in the country, being the Brazilian Northeast responsible for the highest productivity, exerting social and economic importance to the region for bringing profitability to the producers. In this way, the objective of this study is to evaluate the development and use of water from cultivated melon in the Northeastern semi-arid from the accumulated degree-days. Two experiments were carried out at different times during the season 2009/2010, in Fazenda Fruta Vida located in the municipality of Mossoró, state of Rio Grande do Norte, Brazil, where evapotranspiration data were obtained by the method of energy balance by the Bowen ratio. The degree-days accumulated for the 'Sancho' melon were obtained and relation were established between accumulation of dry matter, leaf area index and cultivation coefficient with the cumulative day degrees in each phenological phase and in the whole crop cycle. The results were compared to FAO-56. The relation between day-degrees and leaf area index and dry mass index presented a high coefficient of determination, but the models used to estimate Kc from the degrees-days were not efficient to determine the irrigation management.