Effect of fertilizers and compounds resistance inducers in the agronomic performance of cultivars of processing tomato

Abstract

The Brazilian processing tomato production is concentrated in the state of Goias and accounts for 60% of the national production with average productivity of 87 t ha(‑1), which is above the national average of 70 t ha(‑1). However, both fall short of the real productive potential world that reaches 120 t ha(‑1). This difference is due, among other factors, to the agronomic complexity that is closely related to the high nutritional requirements and to the management of agrochemicals combined with various diseases that affect the culture. The aim of this study was to evaluate the effect of fertilizers with possible phytosanitary action and resistance inducers in the agronomic performance of processing tomato. The experiment was performed in the Agua Limpa Farm, property of the University of Brasilia, using randomized blocks in factorial scheme (8×2), four replicates, eight treatments, two processing tomato cultivars, ‘AP533’ and ‘IPA-6’, and 16 plants plot(‑1). The treatments were: control, potassium phosphite, silicon, biofertilizers, calcium sulfate, biofertilizer, acibenzolar-s-methyl and a chemical mixture of chlorothalonil + copper oxychloride. The spraying was done weekly, up to a total of 10 applications. At the end of the cycle, the harvest was performed with counting and weighing fruit evaluating the estimated yield, yield plant(‑1), number of fruits per plot and the incidence of blossom-end-rot in fruit; these data were subjected to analysis of variance. All treatments showed higher productivity than the national average. The organo-mineral treatment had the highest productivity over against a high rate of blossom-end-rot in the hybrid. The highest yield plant‑1 was obtained with organo-mineral and biofertilizer treatment for ‘AP533’ and silicon, potassium phosphite and organo-mineral for ‘IPA-6’. The treatment acibenzolar-S-methyl and calcium sulphate obtained the lower blossom-end-rot rate. These treatments are promising for improving the nutrition of tomato and reducing pesticide use while maintaining productivity.