Abstract
The longhorn date palm stem borer, Jebusaea hammerschmidtii (Reiche), is a highly destructive beetle of edible date palm Phoenix dactylifera L. The flight capabilities and dispersal potential of this beetle are unknown, which hinders the planning for its proper management in date palm groves. In this study, the flight propensity of this insect pest was investigated using a computerized flight-testing system. The flight system consisted of a flight mill, a digitally controlled testing chamber, and a data logging and processing unit with a USB digital oscilloscope connected with a laptop. A total of 40 field-collected beetles of unknown sex and mating history were used in the experiments; about 34% of this number failed to fly on the flight mill. The relationship between temperature treatments (degrees C) and flight speed (m/min), cumulative flight time (min), and cumulative flight distance (km) of the test beetles were studied using regression equations with correlation coefficients (R-2) of 0.91, 0.98, and 0.98, respectively. The maximum cumulative distance flown by the beetle was 11.5 km at a temperature of 35 degrees C, and a minimum distance of 2.4 km was recorded at 45 degrees C. The flight threshold of the beetle was 20 degrees C, at which flight activities ceased utterly. The velocity of the beetle increased with increasing temperature and reached a maximum of 107 m/min at 40 degrees C, before starting to decline. The obtained information on the flight characteristics of the J. hammerschmidtii may aid in understanding the dispersal of this pest in date palm plantations and in setting up management strategies.