Seasonal incidence of insect-pests of field pea and correlation in relation to weather parameters

Seasonal incidence studies revealed that pod borers and pea aphid were recorded as major pests while grasshopper was minor insect-pests. Peak population of grasshopper (6 grasshopper per quadrate), borers (16 borer larvae/plant) and pea aphid (127 aphids/plant) was recorded on 1^st, 8^th and 4^th standard meteorological weeks (SMW), respectively. Grasshopper population showed negative correlation with minimum and maximum temperature (r = -0.477 and -0.477) as well as with morning relative humidity (r = -0.207). However, evening relative humidity and rainfall show positive correlation with grasshopper population (r = 0.159 and 0.025). Borer population showed negative correlation with minimum and maximum temperature (r = -0.389 and -0.176) as well as with evening relative humidity (r = -0.041). However, morning relative humidity showed mild positive correlation (r = 0.203) and rainfall also had little positive correlation (r = 0.166). Pea aphid population showed negative correlation with minimum and maximum temperature and morning relative humidity (r = -0.464, -0.453 and -0.098, respectively) while it was positive with evening relative humidity and rainfall (r = 0.475 and 0.096).