Comparison between organic and mineral fertilization for soil fertility levels, crop macronutrient concentrations and yield

Interest in soil organic fertilization has grown appreciably in recent years; however, few studies have been performed in greenhouses. A comparative study of organic vs. mineral fertilization in a greenhouse has been conducted for 9 yr in a calcareous loamy soil classified as Xerofluvent in the Guadalquivir River Valley, Seville, Spain. The nutrient availability in the soil, macronutrient concentration in the edible part of the plants, and yield were examined. The organic fertilizer used was vegetal compost and green residue of previous crops that came from the experimental farm and did not depend on external inputs. The use of organic fertilizer resulted in higher soil organic matter, soil N content, and available Pand K. However few differences were found in the macronutrient concentration in the edible part of the crops, independent of the type of fertilization. The nitrate concentration in the edible parts was significantly lower for the crops grown in the organically fertilized plots. Crop yield was not statistically different between fertilizer treatments. This study demonstrated that long-term use of organic compost in greenhouse soil improved soil fertility and produced similar yields and nutrient composition in the edible portion of crops compared with mineral fertilization.

The Spanish Comisión Interministerial de Ciencia y Tecnología (CICYT) for the financial support under the project no. AGL-2000-0493, and to the Junta de Andalucía through the projects PAI RMN-166, and exp. 92162/1.

Peer Reviewed