RESPONSE OF PROCESSING TOMATO TO THREE DIFFERENT LEVELS OF WATER AND NITROGEN APPLICATIONS
The present study was conducted during the 1991 spring-summer season in a processing tomato crop (VF 6203) for three different levels of water and nitrogen applications. Irrigation water levels applied were 0.5, 0.9 and 1.3 times the crop evapotranspiration (ETc) using a highly uniform irrigation system, by means of 360° micro-sprinklers and nitrogen applications were 50, 100 and 150 kg/Ha. The statistical design was a split-plot with 4 replications, where the irrigation was the main factor nitrogen applied was the secondary factor. ETc was estimated with a Campbell Scientific Bowen-Ratio system over a grass field near the experiment site, using FAO 24 crop coefficients. Soil water content was estimated with a CPN neutron probe and gravimetrically. Leaf water potential and canopy temperature data were also collected. Results showed no significative response to the different levels of nitrogen applied. The total yield increased with the amount of water applied, as well as the juice content. However the increase of the application of water reduced drastically total soluble solids content (from 8.04 in the 0.5ETc treatment to 5.53 in the 1.3ETc treatment) being the 0.9ETc of water level applied the most adequate (6.45 soluble solid) for this type of tomato. The crop yield of the 0.9ETc trial was very close to the one obtained in the over-irrigated trial. An over-irrigation or under-irrigation in a processing tomato will produce a low soluble solids content but high crop yield and poor crop yield but high soluble solids content respectively.
Baselga Yrisarry, J.J., Prieto Losada, M.H. and Rodríguez del Rincón, A. (1993). RESPONSE OF PROCESSING TOMATO TO THREE DIFFERENT LEVELS OF WATER AND NITROGEN APPLICATIONS. Acta Hortic. 335, 149-156