Details of this species in Samoa Status: Alien Invasiveness: Invasive Occurrence: Present/controlled Source: Stechmann & Semisi 1984, in PestNet 2002; Voegele 1989; Voegele Klingauf & Engelhardt 1989 Arrival Date: 1980 Introduction: Species Notes for this Location: Brontispa longissima was first recorded in Western Samoa in 1980 (Stechmann & Semisi 1984, in PestNet 2002). Management Notes for this Location: Biological control of Brontispa longissima was used in Samoa and pest leaflets were used for information and education purposes in the mid-1980s (PestNet 2002). Metarhizium anisopliae is a widely distributed soil-inhabiting entomopathogenic fungus. Isolated from Brontispa in several locations is has successfully been used for the control of B. longissima in Samoa and Taiwan. Another fungus, Beauveria bassiana was also shown to be effective against the pest in Samoa when sprayed on coconut trees with 5 x 105 conidia/ml (Rethinam & Singh 2007). Hollingsworth Meleisea & Iosefa (1988, in PestNet 2002) sampled coconut plantations in Western Samoa during early 1985 to identify natural parasitoids and diseases. Chrysonotomyia sp. was the most important cause of larval mortality. An fungus (probably Metarhizium anisopliae) was found on adults in three of the plantations sampled. The pupal parasitoid Tetrastichus brontispae was recovered from only one plantation and was not an important cause of mortality. Chelisoches morio was common in infested coconut spears and fed on larvae and pupae of B. longissima in the laboratory (Hollingsworth Meleisea & Iosefa, In PestNet, 2002) Tetrastichus brontispae has been mass-released in Samoa since 1981. From 1984 to 1987, a steady decline in damage from 42.4 percent to 15.4 percent in was observed due to the biocontrol project. The larval parasitoid, Asecodes sp. was also released between 1981 and 1986. An extensive survey of damage to 37 000 trees in Western Samoa showed that B. longissima was under control and did not cause any significant yield losses. Impacts: Economic/Livelihoods: In Western Samoa initial coconut production losses due to the coconut palm beetle were estimated to be as high as 50 to 70 percent (Voegele 1989). Last Modified: 16/02/2009 1:49:05 p.m.
|