MANAGEMENT OF POTATO LATE BLIGHT THROUGH HOST PLANT RESISTANCE AND FUNGICIDE USE IN SOUTH OMO ZONE, SNNPR, ETHIOPIA

The study was carried out in April 2015 at South Ari district, Senmamer kebele of South Omo Zone Southern Nation Nationality People Regional State to test and demonstrate the effects of integrating host resistance and fungicide application for management of potato late blight disease. In this experiment one relatively late blight resistance improved Irish potato variety (Belete) was collected from Holleta Seed producer Association and susceptible local control potato varieties were used. RCBD with four replications (farmers as replication) were used. A recommended rate of CurzateR R WP fungicide was applied while susceptible local variety developed the first blight symptom. GLM procedures were followed to analyze yield, disease incidence and severity. LSD (P<0.01) values were used to separate treatments mean. Total weight of tubers per plot (kg) was show significant difference (P<0.01) among treatments. The highest total weight of tubers per plot (kg) was given by treated belete (T1) (22.625) followed by untreated belete (T3), untreated local (T4) and treated local (T2) (18.525, 11.875and 10.125) respectively (Table 2).  Local potato variety also gave the highest unmarketable tubers weight per plot. The result indicated that there were a significant difference (P<0.01) and (P<0.05) among treatments on late blight incidence and severity respectively. Untreated local variety (T4) showed highest late blight incidence and severity as compare to treated belete variety (T1). The experiment result suggested that application CurzateR R WP fungicide twice on variety belete results in significant reduction on late blight progress, with a corresponding increased tubers yield.