Effects of Combination of Copper Fungicide and Plant Activator on Late Blight and Quality Criteria of Potato

Abstract

Late blight caused by Phytophthora infestans is one of the most important fungal diseases that cause damage to both the green parts and tuber of the potato plant and limits potato cultivation. Systemic fungicides are mostly preferred by farmers in the control of potato late blight. The fact that systemic fungicides cause health problems in terms of human and environmental health has revealed the need for research on control methods that do not threaten environmental health. In recent years, successful results have been obtained in the control of many diseases with plant activators known as Induced Systemic Resistance (ISR) promoters. This study was carried out in the spring season of 2016-2017 to observe the effect of copper fungicide and plant activator (Lactobacillus acidophilus fermentation product) combination on the control of potato late blight disease and some quality criteria of potato tubers in the experimental plots of Ege University Ödemiş Vocational School in Ödemiş district of İzmir province. The experiment was planned as two separate experiments with Marabel and Melody potato cultivars. The experiment was established according to a split-plot experimental design with four replications. In this study, the effect of the treatments on potato quality and yield criteria such as tuber number, tuber width, tuber length, single tuber weight, yield per decare, and the effects of the pesticides on potato late blight disease and disease severity parameters were evaluated. When the data obtained as a result of the study were evaluated, it was determined that the combination application had a positive effect on the control of potato late blight disease in both potato cultivars compared to the control plots. When the quality criteria of potato tubers were evaluated, the highest number of tubers was obtained from the plots where copper fungicide and plant activator (Isr-2000) combination was applied. Significant increase was obtained in potato quality and yield criteria such as tuber width, tuber length, average tuber weight and yield per decare when the combination plots were compared with the control plots. In conclusion, the use of contact fungicides and plant activator combinations in the control of late blight in the spring period within the scope of sustainable agriculture is promising as an application alternative in the control of plant diseases in organic agriculture.