Seasonal abundance of Helicoverpa armigera (Hubner) on cotton based cropping system in Haryana

A study on seasonal abundance of H. armigera showed that during kharif season, the pest started its activity from the beginning of July in groundnut and then it moved on to cotton and simultaneously also observed on sunflower and bajra. However, from September, the population moved from cotton to pigeon pea but disappeared as the crop reached maturity. During rabi season (2005–06 and 2006–07), the pest was active on chickpea and mustard showing its shifting from pigeon pea. The highest population on chickpea was during February (2005–06) and March (2006–07) when the crop was in pod formation stage. From March onwards the pest survived on summer sunflower and remained up to the beginning of June. Thus, if the host crops are available in a given ecosystem, the pest remains active throughout the year.