Efectividad de la mezcla de izopirazan + azoxystrobin en el control de Alternaria solani y Alternaria alternata en tomate industrial

Abstract

Processing tomato is one of the most important crops in Chile. However, its production is affected by several diseases being the most important those caused by fungi. According to this, appears as important the evaluation of new fungicides with different active ingredients to avoid the appearance of pathogen resistant populations. Diseases associate to Alternaria in this crops can cause important economic damage because rotten fruits are discarded during processing A field experiment (San Clemente, Talca, Chile) was carried out during the growing season 2014-15, to evaluate the efficiency of the active ingredients izopirazam + azoxystrobin at different doses in the preventive control of A. solani and A. alternate. The treatments were ordered in a random block design with 7 treatments and three replications. The treatments evaluated include: izopirazam + azoxystrobin, difenoconazole and trifloxistobin + pirimetanil. A. alternata was inoculated twice, and the fungicides were sprayed five times in a frequency of 14 days. The incidence and severity of early blight and fruit black rot were evaluated.Additionally, at harvest the average weight of 100 fruits was measured for each treatment. The results for incidence and weight were analyzed through an ANOVA and severity using non parametric analysis. Izopirazam + azoxystrobin for both doses presented the best results for incidence and severity for both pathogens. All the treatments resulted statistically similar differing from the treatment without fungicide spray.