The field experiment conducted at Regional Agricultural Research Station, Lam farm, Guntur during 2013-14 on pigeonpea (Cajanus cajan (L) Millsp) yielded a good amount of information on the trend of population build up and seasonal abundance of spotted pod borer, M. vitrata. The larval population/plant gradually increased from third week of November (47th standard week) and reached peak level (12.6 larvae/plant) at the third week of December (51st standard week), which coincides with the peak flowering stage of the crop. The pest remained active up to last week of January. Highly significant correlation was obtained between M. vitrata and minimum temperature, mean temperature and wind speed with correlation coefficient (r) being -0.759, -0.815 and -0.838, respectively. Moderately significant correlation was obtained between M. vitrata and sunshine hours and evening relative humidity (RH-II) with correlation coefficients (r) being 0.656 and -0.609, respectively.
Key words: Maruca vitrata, Pigeonpea, Population, Seasonal incidence.
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