Population dynamics of sucking pest complex of okra with relation to abiotic factors

Abstract

The population dynamics of sucking pest complex of okra with relation to abiotic factors was accessed and found that whitefly appearance on okra crop was first noticed during 27th standard week (1.96/3 leaves) whereas its peak was observed (7.59/3 leaves) during 31st standard week. Similarly, the jassid infestation was first observed during 27th standard week (1.81 jassid/ 3 leaves) but its peak population was found during 34th standard week (14.38 jassid/ 3 leaves). The mite incidence was initially noticed during 27th standard week (1.70 mite/ 2 cm2) and continued till the end of cropping season. However, the highest mite population was found during 36th standard week (13.97 mite/ 2 cm2). Correlation study showed that the maximum temperature and minimum temperature (r = 0.521) had positive and significant correlation with whitefly. However, relative humidity at 7 hrs (r = 0.151) and 14 hrs (r = 0.008) were showed positive but non-significant correlation. Further, whitefly population was found negatively correlated with rainfall (r = -0.020) and had non-significant effect. The jassid population had positive and highly significant correlation with maximum temperature (r = 0.690) while minimum temperature (r = 0.447) and relative humidity at 7 hrs (r = 0.343) showed positive and non-significant correlation. Further, relative humidity 14 hrs (r = -0.366) and rainfall (r = -0.413) showed negative and non-significant correlation. The mite population had positive and non-significant correlation with maximum temperature, minimum temperature and relative humidity at 7 hrs (r = 0.296, 0.171 and 0.215 respectively). Contrary to this, relative humidity at 14 hrs (r = -0.206) and rainfall (r = -0.321) showed negative and non-significant correlation with mite population.