Palms (Phoenix canariensis) infested by red PALM weevil (Rhynchophorus ferrugineus Olivier): insecticidal efficacy tests of chipping treatment

Abstract

The provision n° A6505/29-11-2010 of the Lazio Region Agricultural Department states that the plant material resulting from the felling of palms infested by RPW (Rhynchophorus ferrugineus Olivier) must be disinfested by heat treatment or fine mechanical chipping, ensuring that the resulting materials obtained are of a size smaller than 2 cm. This paper describes changes made on one machine chipper FARMI mod. FOREST CH260 for use in the cutting of trees and palm leaves in accordance with the above mentioned provision. The analyzes carried out on the plant material shredded, according to methodology UNI CEN/TS 15149-1 - 2006, show that 94,78% of the fragments is smaller than 16 mm and a water content of 52.5%. In all fragments of the material shredded at least one of the three dimensions was less than 2 cm. A mix of chipped stipes and leaves of palm tree was tested at ENEA facilities to evaluate the ability of RPW larvae to feed and survive on this substrate. Ten plastic containers (130 liters) were filled up with 26 kg each of chipped matter and infested with larvae grouped by weight into 3 classes ranged from < 0.15 g, 0.15 -;- 0.35 g and > 0.35 g till 2 cm (3 containers for each class and 1 as control; 30 larvae for each container). Containers, covered with a metallic net, were kept in an isolated chamber, controlling temperature in order to maintain the substrate around 30°C. The substrate was inspected at 45 dd after infestation. No survival was recorded on the larvae, indicating that chipping technique could be a suitable method to destroy infested palm avoiding potential risks of re-infestation from the disposal sites.