Estratégia de manejo de água salina na irrigação do meloeiro "Pele de Sapo".

Abstract

The state of Rio Grande do Norte is the second largest exporter of melons from Brazil, the region of Mossoró, which concentrates most of the production. In this region, the scarcity of good water quality, combined with the high cost of funding, has been the main limiting factor for increasing the irrigated area. However, the high availability of saline water, a reduced cost, when managed carefully, can be an economically viable alternative. The objective of this research was to study the effects of water use with low and high salt concentration in the culture of melon, applied alternately, by stage of development of culture or mixed, on soil properties and growth, income and mineral nutrition of cultivars Sancho and Medellin. The study consisted of two experiments, conducted between November 2008 and November 2009 at the Farm Pedra Preta in the city of Mossoró, RN, Brazil. In Experiment 1, the melon (Cucumis melo L., cv Sancho) was irrigated with water of low salinity (ECW = 0.5 dS m"1 ) and high salinity (EC W = 4.3 dS m"1 ) applied daily alternately, varying by crop growth stage or without amendment, totaling 10 treatments. In the second experiment, we repeated some treatments in the fírst trial, plus other treatment that corresponded to a mixture of both types of water, using the cultivars Sancho and Medellin. The experimental design used inExperiment I was a completely randomized design with four replications, as in Experiment II, the factors were arranged in a 6 x 2 split plot with four replications. It was found that the adopted management did not influence the growth characteristics of cv Sancho, the commercial and total yield of both cultivars was not influenced by water use with low and high salt concentration, applied in different forms of management, the management of water saline irrigation of muskmelon was economically feasible, especially in the irrigated treatment in which two days with water of low salinity and a day with saline water, providing a saving of about 33% water of low salinity, the salinity of the extract the saturation was below the salinity of irrigation water with high salt concentration.