Efficacy of different biological and chemical treatments on control of powdery scab of potato

The study assesses the efficacy of biological and chemical treatments to control potato powdery scab at the farmer’s field of Dadeldhura district. The experiment was conducted in a randomized complete block design with 5 treatments and 4 replications. The treatments were Mancozeb, Boric acid, Trichoderma viride, Pseudomonas fluorescens and Non-Treated Control. Cardinal variety of potato was chosen as planting material. The effectiveness of different treatments against potato powdery scab disease was evaluated along with different growth and yield parameters. Significant influences of treatments on disease and yield parameters were observed. Among the treatments, Pseudomonas fluorescens treated tubers showed the least disease incidence (45%) and severity percentage (23.35%). Although, the disease incidence (52.5%) and severity percentage (28.70%) of Trichoderma viride treated plots were found higher but were statistically at par with pseudomonas treated plots while the highest disease incidence (92.5%) and severity percentage (42%) was observed under Non Treated control (NTC). Moreover, Marketable yield (mt ha-1 ) was observed highest from (34.62mt ha-1 ) Pseudomonas followed by Trichoderma viride (28.62mt ha-1 ) and the least yield (15.81mt ha-1 ) was obtained in boric acid) and Non Treated Control (16.76 mt ha-1 ). Similarly, higher returns (NRs. 1315910) and B:C ratio (4.79) were obtained in Pseudomonas fluorescens followed by Trichoderma viride (NRs. 1087795 and 3.97 respectively) and least in Boric acid (NRs.600945 and 2.21). From the results, it can be concluded that antagonistic such as Pseudomonas fluorescens and Trichoderma viride are effective and more economical for reducing potato powdery scab severity and increasing the marketable yield of potato tubers under Dadeldhura conditions.