THE FUTURE OF PROCESSING TOMATO CROPS IN THE EBRO VALLEY LIES WITH THE USE OF BIODEGRADABLE MULCHING

Abstract

This study analyzes the behaviour of different mulches in comparison with the traditional polyethylene mulch, and determines their influence on the yield and industrial quality of a processing tomato crop in two locations in the Ebro Valley, Mendavia (La Rioja) and Cadreita (Navarra). The trial was carried out during 2006, 2007 and 2008 at INTIA’s experimental farm in Cadreita and at the CIDA in Mendavia. Two biodegradable plastic mulches (Mater-Bi® and Biofilm®) were compared, along with two paper ones (Mimcord®, black, and Saikraft®, brown) a PE one and a control without mulching. During the harvest, total yield, commercial yield and the mean weight of the fruit were recorded. The industrial quality parameters pH and °Brix were also determined, as was the break-down of the mulches during the growing season. Despite differences in yields between years and locations, the performance of the mulches was similar, with the highest yields being achieved with the same mulches (PE and Mater-Bi®) in both study areas. In relation to industrial quality, no significant differences were observed between treatments in any of the characteristics analysed. All the mulches studied broke down very well, since in both the biodegradable and the paper mulches the plastic and paper was observed to have disappeared notably by the end of the crop cycle, both underground and on the surface. Based on the results of these trials, we can say that biodegradable mulches are a viable alternative to the use of polyethylene, since no differences were found in industrial quality and yield in comparison to this type of mulch, commonly used by farmers.