Pg. 17-21 Integrated management of litchi pests

Damage surveys of the coconut bug in the Nelspruit and Onderberg areas were completed for the second season. Abortion of stink bug damaged fruit in the Nelspruit region remained constant at ± 45 – 50% while very little damage was observed for the second consecutive year on a number of farms in the Onderberg area. A new stink bug (Leptocoris hexophthalma [Thunberg], Rhopalidae) was observed on litchis in the Onderberg, Nelspruit, Kruger National Park and Hazyview areas. Currently it is expected that incidence of this bug will be of a sporadic nature and no specific precautions are therefore recommended. An application during early October of Cypermethrin 200 g/L EC against the coconut bug significantly reduced early abortion of infested fruit, but final yields of treated trees were not statistically significant different from untreated trees. It was postulated that litchi trees were able to compensate for early crop damage or that C;Oconut bugs only migrated into the orchards at a later stage. A follow-up trial during the 2010 season when lower yields are anticipated is therefore suggested. Isomate reduced the incidence of the litchi moth significantly during the early season, but when insect numbers increased towards the end of the season, differences between treatments were no longer significant.