Determination of the in vitro activities of some chemical applications against important fungal pathogens after harvest in potatoes

Fusarium sambucinum, F. oxysporum, detected after harvest in potato, fungal pathogens such as F. acuminatum, Colletotrichum coccodes and Geotrichum candidum are economically important disease agents for the edible, industrial and seed potato industry. The effectiveness of boron products, which are naturally produced and have antifungal effects, against important fungal disease agents seen in potatoes after harvest in in vitro conditions have been investigated in order to investigate the resistance, residue and environmental damage of pesticides in the world recently and to investigate alternative control methods against pesticides. Among these disease agents, Fusarium sambucinum, Fusarium oxysporum and Fusarium acuminatum potato tubers with dry rot in the form of almost mealy and hard white mycelial mass symptoms, anthracnose disease symptoms that cause black spot symptoms as atypical lesions in Colletotrichum coccodes potato tubers, and sour rubber rot in Geotrichum candidum potato tubers. It produces symptoms that emit an odor and cause soft rot in the tissue it has completely infected. In this study; Survey studies were carried out in potato warehouses in Kavak town of Nevşehir, which has the largest share in potato production as well as potato storage between 2019-2020. As a result of survey studies, 5 different potato warehouses were sampled and examined, and 5 different fungal pathogens that cause important postharvest diseases in potatoes were obtained from 250 tuber samples collected. As a result of morphological and molecular diagnoses, these fungal pathogens were determined to be Fusarium sambucinum, Fusarium oxysporum, Fusarium acuminatum, Colletotrichum coccodes and Geotrichum candidum. It has been determined that boric acid completely inhibits the mycelial growth of pathogens in vitro conditions starting from 0.3% dose of Geotrichum candidum species and 0.5% dose of Fusarium oxysporum and F. acuminatum species. However, although there was no complete inhibition in F. sambucinum and C. coccodes species, it was determined that there was a significant decrease in their development. In the effect of borax on the mycelial growth of pathogens in vitro conditions, complete inhibition was detected in the pathogens of F. sambucinum and C. coccodes at 0.3% dose of Geotrichum candidium species and 0.7% of F. oxysporum and F. acuminatum species. In the effect of boric acid+borax mixture on mycelial growth of pathogens in vitro conditions, it completely inhibited G. candidum at a dose of 0.15+0.3%, F. oxysporum and C. coccodes at a dose of 0.2+0.4%, and F. acuminatum at a dose of 0.25+0.5%. Etidot-67 completely inhibited the mycelial growth of pathogens in vitro in 0.2% of G. candidum, 0.4% of F. oxysporum and C. coccodes, and 0.65% of F. acuminatum.The aforementioned study is the most comprehensive and original study conducted in our country to determine alternative control methods against postharvest fungal diseases in potatoes.