Potato Late Blight (Phytophthora Infestans (Mont.) de Bary) Disease Development and Tuber Yield with Response to Planting Dates and Fungicides Application In Nepal
S. GAIRE (1) (1) Agriculture and Forestry University, Nepal

A field experiment was conducted to find out the effects of different planting dates and fungicides in the control of potato late blight (Phytophthora infestans (Mont.) de Bary) on commercial TPS potato, variety HPS 7/67, at Rampur, Chitwan, during October 2011- March, 2012 under natural epidemiological conditions. The study consisted of four different planting dates, starting from 25 th Oct. at ten days intervals and three fungicidal sprays (Acrobat, Dithane M-45, Jeebatu) and without spray as a check in split plot design with three replications. Planting dates were assigned to the main plots and fungicides to the sub-plots. The data revealed highly significant (p<0.01) difference between dates of planting for RAUDPC and tuber yield (t ha -1 ). Potato planted on 25 th Oct. showed minimum RAUDPC value (0.34) of late blight and maximum tuber yield (16.65 t ha -1 ). Delaying in planting time, there was increased in RAUDPC value and decreasing tuber yield. Fungicides application was found highly significant (P<0.01) on RAUDPC and tuber yield (t ha -1 ). Acrobat sprayed plot had minimum RAUDPC (0.2114), maximum tuber yield (11.86 t ha -1 ). The increase in tuber yield over check was also highest in Acrobat-sprayed plots (67.63%), followed by Dithane M-45 (63.25%), and minimum in Jeebatu (5.98%). Considering disease development, tuber yield, efficacy and cost of fungicide application, Plantation of potato on 25 th October and Dithane M-45 spray just after initiation of disease resulted most effective management of late blight of potato.

Abstract Number: P17-524
Session Type: Poster