Influence of weather parameters on Aphis craccivora and Bean common mosaic virus disease incidence in Vigna unguiculata L. Walp

ABSTRACT

Aim: Many crop modelling and climate simulation studies have reported variability in pest and pathogen distribution as well as their interaction with host. These prediction encourages to revisit the pest and pathogen epidemological and distribution studies in light of changing climate. In line with above assumption, the present field study was carried out to study the population dynamics of cowpea aphid (Aphis craccivora) and its influence on BCMV disease incidence. Methodology: In this field experiment, A. craccivora population and BCMV disease incidence data were collected in different standard meteorological weeks of 2013-2014 and 2014-2015. Impact of weather parameters on A. craccivora and BCMV disease incidence was statistically analyzed. Results: The significant change in A. craccivora population and BCMV disease incidence was documented during the study. The maximum aphid population was observed during rabi season and less was observed in kharif and summer season. Whereas, incidence of BCMV was recorded maximum in rabi season. Correlation analysis affirmed, minimum temperature (Tmin) and rainfall had negative impact on A. craccivora whereas weather parameters had non-significant impact on BCMV disease incidence. The regression models developed from the present study explained 41.4 % to 78.8 % and 18.5 % to 46.1% variability (R2) of aphid population and BCMV incidence, respectively. Interpretation: The weather parameters had more impact on A. craccivora population than BCMV disease incidence and merely presence of maximum number of A. craccivora was not a deciding factor for outbreak of virus disease incidence.