Tomato seedlings soilless culture on K+, Ca2+ or Mg2+ loaded zeolite and different granule size

Zeolites are minerals of the hydrated aluminosilicates group with porous structure, high cation exchange capacity and moisture retention. Their physical and chemical characteristics make them an attractive substrate for soilless culture. The study consisted of determining the physical properties and cation exchange of clinoptilolite zeolite, for its posterior evaluation as a soilless substrate, loaded with K+, Ca2+ of Mg2+, each of them in three particle sizes: 0.71-1.00, 1.01-2.00 and 2.01-3.36 mm, on yield and nutrient absorption of tomato (Lycopersicon esculentum Mill.) seedlings cv. Mitsuri. A complete factorial design 32 was used; three particle sizes of tezontle (porous volcanic lava) were also included as controls. K+ was the most efficient cation (p <= 0.05) to displace Na+ in the natural zeolite. Zeolite loaded with K+ or Mg2+ produced seedlings of greater size than those obtained with zeolite with Ca2+. Seedlings established in tezontle of the largest particle size were shorter than those grown in the corresponding zeolite group.