Discover the Most Effective Disease Management Strategies for Fusarium Dry Rot of Potato through Comprehensive Bio-assay of Three Techniques (Chemical, Plant extracts, and Bio-control)

Abstract

Potato (Solanum tuberosum) is a multicultural staple food and cash crop. Unfortunately, production of potatoes is predominantly constrained by diseases including dry rots. To evaluate management of dry rots, three in vitro sub-trials were set up using the completely randomized design with each treatment replicated thrice for each trial. Firstly, synthetic fungicides were assayed against Fusarium oxysporum f.sp. tuberosi. Secondly, plant extracts were assessed against F. oxysporum. Finally, the efficacy of Trichoderma harzianum applied against F. oxysporum was evaluated. The colony radii were measured. The inhibition of F. oxysporum by Ketoconazole (at 100% concentration) was significantly (p≤0.05) highest, followed by Ketoconazole (50% concentration), Itraconazole (100% concentration), Itraconazole (50% concentration), Sulphur (100% concentration), Ridomil (100% concentration), Sulphur (50% concentration), and finally Ridomil (50% concentration). Percentage inhibition of the growth of the Fusarium species by fungicides ranged from 39.5-95.7%. Blue gum (Eucalyptus globulus) (at 100% concentration) gave the highest inhibition, followed by blue gum (50% concentration), Sweet alligator-pepper (Aframomum melegueta) at 100% concentration, locust bean (Parkia biglobosa) at 100% concentration, Sweet alligator-pepper (50% concentration), candle bush (Senna alata) (100% concentration), locust bean (50% concentration), and Senna alata (50% concentration) in descending order of percentage inhibition. Plant extracts caused a percentage inhibition of the fungus between 20.6-100% inhibition with time. Inhibition of Fusarium by T. Harzianum isolate BGMZ4 was significantly (p≤0.05) highest, followed by T. Harzianum isolate NSBM then T. Harzianum isolate BGMZ3. Control of F. Oxysporum by T. Harzianum ranged from 23.5-94.1% inhibition. All the methods evaluated successfully inhibited the pathogen compared to the control.