Seasonal Abundance of Fulgoraecia melanoleuca (Fletcher), a Key Parasitoid of Pyrilla perpusilla (Walker) in Different Agro-Climatic Zones of Punjab, India

The study on seasonal abundance of ectoparasitoid Fulgoraecia melanoleuca (Fletcher) life stages and its parasitism on host P. perpusilla (Walker) was conducted in the sugarcane fields selected one each from three different agro-climatic zones of Punjab, i.e. Hoshiarpur (sub-mountainous undulating zone), Jalandhar (Central plain zone) and Fazilka (south-western zone). The population of parasitoid increased with increase in the host population, indicating a density-dependent relationship between them. Among different agro-climatic zones, population count of P. perpusilla and F. melanoleuca as well as natural parasitism on sugarcane crop was more in central plain zone as compared to sub-mountainous undulating zone and was lowest in south-western zone. The total parasitism (nymphs + adult) reached its peak during the second fortnight of September at Hoshiarpur (25.27%) and Fazilka (8.28%). However, it was maximum in the first fortnight of September at Jalandhar (27.60%). Both host and parasitoid populations showed a small peak in the month of May; however, there was decline in the June month. It again accelerated from the month of July and continued to increase abruptly at the faster rate reaching peak in the September month. Thereafter, the population showed a declining trend. During winter months from December to March, the parasitoid F. melanoleuca overwintered in egg and pupal stage (cocoon) on leftover sugarcane trash to overcome unfavourable low temperature and again became active on spring sown crop during the month of April. However, the overwintering was predominantly in the cocoon stage. The findings will help in devising an effective augmentative biological control programme against this pest.