Effects of Date of Planting on Red Ant (Dorylus orientalis) Management and Tuber Yield of Potato

An experiment was conducted to identify the appropriate time of planting for red ant management and increase the tuber yield of potato at Agriculture Research Station (ARS), Jaubari, Ilam, Nepal (2900 masl) during 2020 and 2021 planting season. Seed potatoes were planted in 9 different plant dates that were December 1, December 15, January 1, January 15, February 1, February 15, March 1, March 15 and April 1. The experiment was laid out in Completely Randomized Block Design (RCBD) with three replications. The variety used for experiment was Janakdev. The plot size for the experiment for each treatment was 4.5m2 with spacing of 75 cm x 25 cm. Data were collected on vegetative characteristics, tuber yield parameters, red ant damage scoring (1-5 scale), red ant incidence (%) in tuber and red ant infested yield (t/ha). Potatoes planted at first January produced highest tuber yield and minimum red ants infestation. Early planting delayed emergence but had maximum ground coverage. In both the years tuber was highest (19.86 t/ha and 25.48 t/ha respectively in 2020 and 2021) with seed tuber planted on January 1. Tuber yield was less both in early and late planted potatoes. Along with higher tuber yield potatoes planted on January 1 had the lowest red ant damaged score, red ant incidence (%) and less red ant infested potato tuber yield (t/ha) in both the years. It is recommended that for maximum tuber yield and minimum red ants infestation seed potatoes should be planted during first week of January in Jaubari area and similar conditions in the hills of Nepal.