Effects of dolomite and borax on the quality of Tainung No. 13 pineapple

摘要

Pineapple(Ananas comosos (L.) Merr.) is one of the important fruits in Taiwan. Prior to flower-initiation, Tainung No. 13 contains generally lower concentration of calcium (Ca), magnesium (Mg) and boron (B) in leaves than Smooth Cayneen. This study was conducted to evaluate the supplement of calcium (Ca), magnesium (Mg) and boron (B) by the field application of dolomite and borax to improve the quality and reduce broken-cored disease in Tainung No.13. A randomised complete block design (RCBD) with three replicates and nine treatments of three dolomite rates (i.e. 0, 1, and 2 ton ha-1) and three borax rates (i.e. 0, 15, and 30 kg ha-1) with control treatment was designed in this study. Variations of the soil physical and chemical properties and concentrations of nutritional elements in the leaves before flower-forcing were estimated. Increasing application of dolomite and borax showed a tendency to raise the nutritional elements in both soil and leaf. The fruit length, width and weight were the best by the application of 30kg ha-1borax. The fruit sugar/acidity ratio and percentage of broken-cored disease were both improved when 2 ton ha-1dolomite and 30 kg ha-1borax were applied. This study demonstrated that the supplement of Ca, Mg and B was able to improve the quality of Tainung No. 13 pineapple.