author(s)
Parul Dobhal, RP Maurya, VR Bhatnagar and L Brijwal

abstract
Manipulation of date of sowing of crops is an important cultural practice to avoid the peak infestation of insect pests on the crop. Hence, present investigation was carried out to study the impact of sowing dates on the incidence of insect pests of pigeonpea in the Tarai region of Uttarakhand during 2016 and 2017. Four different sowing dates (viz, 10^th June, 20^th June, 10^th July and 10^th August) were selected for this study. The crop sown at 10^th June showed significantly lower incidence of Empoasca kerri, Clavigralla gibbosa, Helicoverpa armigera and Maruca vitrata at early stage of the crop as against to other three sowing dates. Hence, the crop was escaped from early infestation of insect pests. The percent pod damage caused by H. armigera (1.85%) and M. vitrata (12.80%) was also found to be lowest on the crop sown at 10^th June, while the pod damage by M. obtusa was lowest (21.05%) on the late sown crop (10^th August). The yield data indicated that the crop sown on 10^th June recorded significantly higher yield (1219 kg/ha) as compared to subsequent sowing, while the lowest yield (747 kg/ha) was noticed in crop sown on 10^th August. Thus, this study showed that the first flush of the pigeonpea crop was escaped from peak activity of the M. vitrata, H.armigera and other sucking pests at early sowing. It is, therefore, 10^th June would be the most suitable date of sowing for pigeonpea in the Tarai region of Uttarakhand.