Evaluation of Fulgoraecia melanoleuca (Fletcher) (Lepidoptera: Epipyropidae) Releases for the Management of Pyrilla perpusilla (Walker) (Hemiptera: Lophopidae) on Sugarcane in Punjab, India
摘要
Fulgoraecia melanoleuca (Fletcher) is an important ecto-parasitoid of Pyrilla perpusilla (Walker) nymphs and adults. The study aimed to standardize the augmentative releases of F. melanoleuca life stages (eggs and cocoons) for eco-friendly management of P. perpusilla in sugarcane crop. The releases of F. melanoleuca cocoons (2000, 4000, and 6000 cocoons ha−1) and eggs (0.2, 0.4, and 0.6 million eggs ha−1) were compared with chemical control (chlorpyriphos 20 EC @1500 ml ha−1) and untreated control. Two releases were carried out at monthly interval during 1st week of August and 1st week of September. The pyrilla population decreased progressively with increase in released cocoons (2000, 4000, and 6000 ha−1) and eggs (0.2, 0.4, and 0.6 million ha−1). The augmentative releases play a noteworthy role in increasing the parasitoid count (egg masses, cocoons and adults) in the released plots. Overall, the parasitism (nymph + adult) increased with increase in doses and it was significantly higher when parasitoids were released at higher doses, i.e. 0.6 million eggs ha−1 (52.80%) and 6000 cocoons ha−1 (50.60%). However, chlorpyriphos 20 EC (1500 ml ha−1) was found to be highly detrimental to the parasitoid as no parasitism was observed in insecticide-sprayed plots. In conclusion, two releases of F. melanoleuca parasitoid (0.6 million eggs ha−1 or 6000 cocoons ha−1) at monthly interval (1st week of August and 1st week of September) proved better due to higher parasitism rate, increase in parasitoid population, and reduction in pyrilla population and also rendered higher cane yield and better juice quality. The findings will help in the eco-friendly management of P. perpusilla in sugarcane.