Management of Pyrilla perpusilla Walker in sugarcane with ecto-parasitoid Epiricania melanoleuca Fletcher during epidemics in sub-tropical India

Abstract

The bio-suppression of sugarcane leaf hopper, Pyrilla perpusilla Walker during epidemics in 2007 by its potential nymphal and adult ecto-parasitoid, Epiricania melanoleuca Fletcher in command area of three sugar mills of Uttar Pradesh covering an area of approximately 40,000 ha with commendable success could serve as a model for pest management in other areas also. The sugarcane Pyrilla, which initially appeared on wheat, fodder sorghum, barley and grown up sugarcane, later migrated to autumn, spring plant and ratoon during March-April. The over wintering population of nymphs survived to a great extent due to mild winter which favored the fast multiplication of nymphs into adults. These nymphs developed into adults during March and started breeding profusely and caused the havoc. The population of Pyrilla and its parasitoid was assessed during rapid roving survey. The leaves bearing parasitoids were redistributed in sugarcane fields @ 5000 cocoons + 5 lacs eggs/ha or 10000 cocoons/ha in absence of eggs of Epiricania. The E. melanoleuca played a major role to control the Pyrilla population. The insecticidal spraying operation, which was not recommended, resulted in a saving of about Rs.1600/ha besides avoiding environmental pollution. The splendid control of the Pyrilla epidemic has once again proved that conservation of natural enemies and augmentation through field redistribution could be effective components in bio-suppression of Pyrilla. Hence, it is inferred that if ecto-parasitoid Epiricania melanoleuca cocoon is available in field @1–5/leaf at Pyrilla population level ranging from 20 to 150 nymphs+adults/leaf, the insecticides should not be sprayed at all.