Resumen

BERNARDI, Alberto C. de Campos et al. Dry matter production and nutrient accumulation after successive crops of lettuce, tomato, rice, and andropogongrass in a substrate with zeolite. Rev. Bras. Ciênc. Solo [online]. 2010, vol.34, n.2, pp. 435-442. ISSN 0100-0683.  http://dx.doi.org/10.1590/S0100-06832010000200017.

Zeolites are hydrated crystalline aluminosilicate minerals of natural occurrence, structured in rigid third dimension net that can be used as slow release plant-nutrient source. The main objective of this study was to evaluate the effects of plant growth substrate under zeolite application, enriched with N, P and K, on dry matter yield and on nutrient contents in consecutive crops of lettuce, tomato, rice, and andropogon grass. The experiment was carried out in a greenhouse, with 3 kg pots with an inert substrate, evaluated in a randomized block design with three replications. Treatments consisted of four types of enrichment of concentrated natural zeolite: concentrated zeolite (Z) only, zeolite + KNO₃ (ZNK), zeolite + K₂HPO₄ (ZPK) and zeolite + H₃PO₄ + apatite (ZP), and a control grown in substrate fertilized with a zeolite-free nutrient solution. Four levels of enriched zeolite were tested: 20, 40, 80, and 160 g/pot. Four successive crops were grown on the same substrate in each pot: lettuce, tomato, rice, and andropogon grass. Results indicated that N, P and K enriched zeolite was an adequate slow-release nutrient source for plants. The total dry matter production of above-ground biomass of four successive crops followed a descending order: ZP > ZPK > ZNK > Z.

Palabras llave : stilbite; Lactuca sativa; Lycopersicum esculentum; Oryza sativa; Andropogon gayanus; slow-release fertilizer; growth substrate.