Effect of Distribution Uniformity and Fertigation Volume on the Bio-Productivity of the Greenhouse Zucchini Crop

Abstract

Greenhouse horticultural crops are characterized by high levels of efficiency and productivity of irrigation water and nutrients applied. However, these indices may be affected by poor distribution uniformity of fertigation (DU). Different previous prospective studies show that there is a significant percentage of facilities with a low level of DU. However, there is no precise relationship between DU and the efficiency and productivity of water and fertilizers. This relationship may be affected by different factors, especially by the irrigation dose. The objective of this work was to determine the effect of the distribution uniformity of fertigation and the fertigation volume (FV) on the bio productive parameters and efficiency of water and nutrient use of the zucchini crop. The trial was developed in a greenhouse located in La Mojonera (Almería), on sanded soil. The greenhouse was equipped with an automated fertigation installation. The experimental design was randomized complete blocks with six treatments and three repetitions. The established treatment was a combination of two factors: distribution uniformity and fertigation volume. Three levels of DU were established: 100%, 75% and 50% approximately and two levels of fertigation volume: FV100% and FV70%. Volume of water and nutrients applied, soil matric potential (SMP), yield, biomass and efficiency in the water and nutrients use were determined. The maximum efficiency in the use of water and nutrients was obtained with a DU of 100% or 75% and a fertigation volume of FV70%, but this fertigation volume reduced the bio-productive parameters of the crop such as yield. The maximum yield and biomass were obtained with the volume of fertigation of 100% (FV100%), and with a DU of 100% or 75%. DU50% level reduced all bio-productive parameters, reducing yield by 45%, as well as the water use efficiency (WUE) and nutrient efficiency with any level of fertigation.