Comparative analysis of calcium sources in greenhouse 'Galia' muskmelon

'Galia' muskmelons, Galileo hybrid, were grown at Embrapa Hortaliças in Brasilia, Brazil, in a greenhouse in pots, from September to December 2001. Five calcium treatments were evaluated (liming and liming plus fertigation with calcium nitrate, calcium buffered, calcium chelates and calcium chloride), besides the control without calcium (Ca). The experimental design was of randomized blocks with 6 treatments, 4 replications and 6 plants per plot. Overall calcium application increased marketable yield (kg m-2) by 26% and the number of fruits by 21%. These results indicated the need of Ca fertilization in soils with base saturation lower than 70%. Liming plus calcium fertigation increased yield and the number of marketable fruits by 30% and 27%, respectively. Thus, Ca fertigation was more effective than liming. Fertigation with calcium nitrate and calcium chloride presented the highest profitability. No effect was observed on the average fruit weight. No significant effects on treatments were obtained for pulp thickness, soluble solids content (Brix), total titratable acidity (TTA) and Brix/TTA ratio. In conclusion, Ca must be applied to greenhouse muskmelon for soils with base saturation lower than 70%. Liming plus Ca fertigation was more profitable than only liming. Fertigation of Ca-nitrate or Ca-chloride was more profitable than liming plus Ca treatments (liming and liming plus fertigation with Ca-buffered or Ca-chelates).

Cucumis melo L. var. reticulatus; liming; fertilizers; drip irrigation; fertigation; base saturation; fruit quality

Associação Brasileira de Horticultura UFRPE (Universidade Federal Rural de Pernambuco, Rua Manoel de Medeiros s/n, Dois Irmãos,, 52171-900 Recife-PE, Tel. (81) 3320 6064, - Vitoria da Conquista - BA - Brazil