The effect of weaver ants Oecophylla smaragdina on the shoot borer Hypsipyla robusta on African mahoganies in Australia

Abstract

1 African mahogany Khaya senegalensis is a high-value timber tree species widely grown in central Africa, south-east Asia and northern Australia. Pilot plantings show that the tree grows well in the wet-dry tropical areas of northern Australia, and the shoot borer Hypsipyla robusta (Lepidoptera: Pyralidae) is a potential pest of the tree. The weaver ant Oecophylla smaragdina is an efficient biocontrol agent in some horticulture crops. To investigate whether the ants control shoot borers, field experiments were conducted at two sites near Darwin, Australia from April 2006 to January 2009. 2 In the weaver ant treatments, the overall percentage of trees damaged by shoot borers was 0-2.7% at Berrimah Farm and 0-4.2% at Howard Springs, and the damaged trees were attacked once only. In the treatments without weaver ants, however, 9.9-52.1% trees were damaged at Berrimah Farm, and 6.3-64.6% at Howard Springs, and the damaged trees were generally attacked more than once. 3 At both sites, significantly fewer trees on each monitoring occasion were damaged in weaver ant treatments than in treatments without weaver ants. 4 The mean percentage of overall flushing shoots damaged by the pest at both sites was significantly lower in weaver ant treatments compared with treatments without weaver ants. 5 Fewer shoots were damaged per damaged tree in weaver ant treatments compared with treatments without weaver ants. 6 The data obtained suggest that weaver ants were effective biological control agents of the shoot borer, and that the ants can be used to manage the pest on African mahogany trees.

Biological control of the fruit‐spotting bug Amblypelta lutescens using weaver ants Oecophylla smaragdina on African mahoganies in Australia

“…In the present study, in the treatments without weaver ants, over 80% of trees at Berrimah Farm and 30-100% of trees at Howard Springs were attacked by fruit-spotting bugs (Table 1), and 10-65% of trees at Berrimah Farm and 10-52% at Howard Springs were attacked by Hypsipyla shoot borers (Peng et al, 2011b). robusta is essential.…”

Using weaver antsOecophylla smaragdinato control two important pests on African mahoganyKhaya senegalensisin the Northern Territory of Australia

“…As African mahoganies are widely distributed in tropical and subtropical African countries, and new plantations are heavily attacked by Hypsipyla shoot borers (Opuni-Frimpong et al 2008), it would be worthwhile conducting an assessment of the effects of local O. longinoda ants on the shoot borers and other pests on African mahoganies in tropical Africa. Peng et al (2011b) reported that O. smaragdina is an effective bio-control agent of Hypsipyla shoot borers on African mahogany trees in the Northern Territory.…”

“…Alexander). The impacts of fruit-spotting bugs and shoot borers and the control strategies have been reported (Peng et al 2011b(Peng et al , 2012. Although the damage caused by the yellow looper and bush crickets does not kill the trees, the resultant stem deformation reduces the production of timber (Peng et al 2009).…”

“…Wylie 1974;Macfarlane et al 1976;Lim and Kirton 2003;Peng et al 2010aPeng et al , 2011bPeng et al , 2012 and in horticultural crops (e.g. Stapley 1972;Huang and Yang 1987;Van Mele et al 2002;Peng et al 2004Peng et al , 2010bPeng and Christian 2005a).…”

Comparing different methods for trapping mated queens of weaver ants (Oecophylla longinoda; Hymenoptera: Formicidae)

“…Being generalist predators, Oecophylla spp. can significantly reduce the abundance of several insect pests of tropical crops (Adandonon, Vayssières, Sinzogan, & Van Mele, 2009;Peng & Christian, 2004;Peng, Christian, & Gibb, 1995;Peng, Christian, & Reilly, 2011;Way & Khoo, 1989). Furthermore, Oecophylla ants are targeted as mini livestock for sustainable protein production, as they are used as food by humans and animals (Cèsard, 2004;FAO report, 2013;Offenberg, 2011;Sribandit, Wiwatwitaya, Suksard, & Offenberg, 2008;Van Itterbeeck, Sivongxay, Praxaysombath, & Van Huis, 2014).…”