A Survey of Wood Borer Apate terebrans Tunnels on Terminalia mantaly in Nigeria with Special Reference to the Niger Delta Region

Abstract

This study was conducted to count Apate terebrans opened tunnels in Terminalia mantaly at the 3 Parks of the University of Port Harcourt. All trees were assessed visually for the presence and absence of tunnels, frass, and exudates during the 6-months (January-July) field survey in 2018. The mean numbers of tunnels/tree were 16.12±2.13 from 58 trees representing 19.9% of 291 total trees. The spread of attack was fairly scattered and more closely associated with diameter at breast height (DBH) of tree (χ2= 12.763, df = 4, α0.012*). While a majority (67.0%) of the trees experienced breaking reflecting both the immediate and residual impact of opened and closed tunnels, respectively, 10.7% experienced tearing of branches, and 5.5% experienced both breaking and tearing. Strong wind was found as a contributory factor to breaking and tearing. The findings suggest T. mantaly as a poor adaptable environmental species in Nigeria ecosystems and its current utilisation as ornamental tree may be revisited. Contribution/Originality:This study documents the resurgence of wood borer, Apate terebrans and its impacts on the Terminalia mantaly used as one of the current popular urban trees in Nigeria. INTRODUCTIONA world-wide-spread problem in wood utilisation is related to the protection of wood products that are often attacked by insects. The same problem is encountered in the environmental utilisation of trees (living woods). Until now a satisfactory solution to control the trees' degradation by wood-boring beetles had not been found, and the applied conservation methods offered only temporary reduced controls [1, 2] without guaranteeing a real and durable effectiveness. Beetles are one of the major devastating pests of plants worldwide with many types economically, environmentally and socially attacking healthy trees [3,4]. Among these, wood-boring beetles are the most common disturbance of trees worldwide [5,6] with a high prevalence from Bostrichidae [7, 8] and higher incidence in introduced species than native ones [9]. The black beetle, Apate terebrans (Pallas, 1772) (Coleoptera: Bostrichidae), is a widely distributed pest in Africa and Neotropical climes [10,11]. Also, the occurrence of this beetle in Austria, and Europe has been reported [1]. Its primary hosts include many agricultural and forest trees [12]. In Nigeria, Murray [13] in 1867 listed A.