Arthropods as possible loss or solution sources on Acacia mangium (Fabales: Fabaceae) saplings

Abstract

Acacia mangium (Willd.) (Fabales: Fabaceae) tree shows applicability in programs to recover degraded areas due to its fast-growing, rustic, pioneer species, with the potential to fix nitrogen. However, this plant is attacked by pests. It is important to know, among them, the most important. This study aims to evaluate the herbivorous insects (loss sources) and their natural enemies (solution sources) on 48 A. mangium saplings. They were classified according to their ability to damage or reduce the source of damage on these saplings using the percentage of the Importance Index-Production Unknown (% I.I.-P.U.). The loss sources Trigona spinipes Fabr. (Hymenoptera: Apidae), Aleyrodidae (Hemiptera), Phenacoccus sp. (Hemiptera: Pseudococcidae), Aethalion reticulatum L. (Hemiptera: Aethalionidae), and Tropidacris collaris Stoll. (Orthoptera: Romaleidae), showed the highest % I.I.-P.U. on leaves of A. mangium saplings. The solution sources Oxyopidae (Araneae), Pseudomyrmex termitarius (Smith) (Hymenoptera: Formicidae), and Brachymyrmex sp. (Hymenoptera: Formicidae), showed the highest % I.I.-P.U. on leaves of A. mangium saplings. The number of Lordops sp. (Coleoptera: Curculionidae) was reduced per number of Brachymyrmex sp.; that of T. collaris those of Oxyopidae and Brachymyrmex sp.; and that of Tettigoniidae that of P. termitarius, totaling 8.93% of reduction of these herbivorous insects (numbers) on A. mangium saplings. These herbivorous insects turn into problems in commercial plantations of this plant since to are related to pests in some crops. These tending ants and Oxyopidae can be important on A. mangium commercial crops because they can reduce the number of these herbivorous insects.