Foliar Application of Fungicides Registered Against Late Blight Influences Main Potato Tuber Diseases and Key Quantitative Characteristics of Tubers

Abstract

Adequate integrated management of potato leaf diseases can have an influence on pathogens which are challenging to control and cause main potato tuber diseases. Deriving from this hypothesis, an experiment was designed to evaluate the efficacy of foliar application of twelve fungicides on late blight in tubers, common scab, black scurf and silver scurf. In the period of 2013 to 2017, the fungicides were equally applied six times in registered doses during the growing seasons. Eight tuber disease indicators and eight yield characteristics were then evaluated in harvested tuber samples. Significant differences were found among the fungicides used. In comparison to the negative control (n. c.), the application of Infinito, Ranman Top and Revus Top reduced the quantity of tubers infected by late blight by 72% on average. The incidence of common scab increased by 65% of n. c. under the effect of copper oxychloride, while an average reduction by 19% of n. c. was observed with the use of Acrobat MZ WG, Curzate Gold and Consento. The occurrence of silver scurf was significantly enhanced by Curzate Gold and Consento (105% of n. c.), while it was suppressed by Revus Top and Revus (85% of n. c.). All fungicides were ineffective on black scurf yet had a positive influence on the potato yield and quality, with the choice of fungicide having a great impact on the quality of tubers. The application of any safe fungicide is important, especially in years similar to 2015, which was the most devastating recent year for potato production in terms of structural changes in yield of tubers.

Combined effects of fungicides formulations and potato varieties on late blight management, yield and net farm income in Kenya

“…This approach is insufficient and unsustainable. Studies on the use of biocontrols (El-Hasan et al, 2022), seed dressing (Wharton et al, 2012), cultural practices (Hussain et al, 2013) and integrated late blight management (Sedlák et al, 2022); Khadka et al (2020); Kassaw et al (2021) have also been proposed. Unfortunately, biocontrol methods (one of the eco-friendly approaches) are not yet effective to suppress the disease (Yao et al, 2016;Kilonzi et al, 2020).…”

Endophytic Bacillus subtilis H17‐16 effectively inhibits Phytophthora infestans, the pathogen of potato late blight, and its potential application

“…is the most important means. 6,7 However, long-term overuse of chemical fungicides may lead to environmental pollution, food safety and human health threats. 8 Moreover, Phytophthora infestans can quickly develop resistance to fungicides, making them ineffective.…”

“…Chemical control by spraying fungicides (infinito, mancozeb, fluazinam, dimethomorph, cyazofamid, etc.) is the most important means 6,7 . However, long‐term overuse of chemical fungicides may lead to environmental pollution, food safety and human health threats 8 .…”