Improving Nitrogen Availability and Ananas comosus L. Merr var. Moris Productivity in a Tropical Peat Soil Using Clinoptilolite Zeolite

Abstract

Pineapple cultivation in nitrogen deficient and acidic peat soils leads to poor growth, yield, and fruit quality of pineapples. A study was conducted to determine whether clinoptilolite zeolite (CZ) could improve soil nitrogen availability, growth, yield, and fruit quality of pineapples grown in drained peat soils. Laboratory leaching experiments were conducted to determine the effectiveness of CZ in controlling nitrogen loss from peat soils, whereas an ion-exchange resin method was used to determine nitrogen availability in pineapple cultivation. Treatments evaluated were: (i) different amounts of CZ (25, 50, 70, and 100%) + NPK fertilizer, (ii) NPK fertilizer, and (iii) peat soil only. The peat soils with CZ reduced ammonium and nitrate losses because of the sorption of ammonium within the lattices of the CZ via ion exchange. Co-application of CZ (25%) and NPK fertilizers was more effective in increasing soil ammonium availability, whereas the use of CZ (25% to 100%) improved nitrogen uptake and use efficiency, growth, yield, and fruit quality of pineapple because CZ could regulate the availability of nitrogen ions for pineapple uptake. The buffering capacity of CZ increased soil pH and facilitated organic nitrogen mineralization. The co-application of CZ and NPK fertilizers can be used to improve nitrogen availability and pineapple productivity in tropical peat soils.