Ecological interaction of leaf and fruit scarring beetle (Nodostoma viridipenne) of Banana in Assam

The beetles fed on young leaves and fruits by making scars; thereby reducing the yield and market value of the fruits in particular. Population of this pest started increasing with the raise of atmospheric temperature from March onwards to reach its maximum during August- September and gradually decreased from October and reached its minimum during January-February. Lower activity of the pest was observed during the winter months. Number of leaf scars also increased or decreased in relation to the population of scarring beetle on each plant. A significant positive correlation was observed between the population build up as well as number of leaf scars with climatic factors, like maximum and minimum temperatures and rainfall. Correlation of both the dependent variables with relative humidity was non significant and negative. Regression equation explained 93–95 and 88–96% variability of beetle population and leaf scars due to weather parameters, respectively.