INSECTS ASSOCIATED WITH Terminalia ivorensis A. CHEV. IN FACULTY OF AGRICULTURE, UNIVERSITY OF BENIN, BENIN CITY

ABSTRACT

The study was carried out to evaluate the insects associated with Terminalia ivorensis, identify and study the stages of these insect and proffer a possible solution to these attacks. Ten(10) stands of Terminalia ivorensis were randomly selected from a mixed plantation of timber species in Faculty of Agriculture, University of Benin, Benin City. The stands were selected based on height of the first branches for ease of data collection. The stands were tagged T₁, T₂, T₃…………T₁₀. The stands were visited once in a week for a period of ten weeks. Observation was made early morning and in the evening per visit to the stands. Data collected were species of insects, numbers of insects present, damage done the parts of plant affected. A total of 1149 insects belong to five orders and ten (10) species were observed during the course of this study. Coccinnella septempuntata (lady beetle) had the highest (50%) abundance. This was closely followed by Hetenonychus arata (black beetle) 49%, while the least were Reduvius personatus (True bugs) and Componotus pennysulvanicus (Capenter ant) with 0.1% each. The data collected were analyzed using descriptive statistics of frequency and percentages summarized in table and chart, and inferential statistics with the use of analysis of variance (ANOVA) at 5% significance. Duncan multiple range test was used to separate the means of variables. The mean weekly insect observed on the sampled trees ranges from 8.6 to 14.8. The result revealed significant difference (P<0.05) in insects observation among the sampled trees. Insect observed in sample tree 1 dominated every other trees considered for this study. Based on this insect survey carried out, it is then concluded that there are two main species of insects associated with Terminalia ivorensis in this zone which are Coccinella septempunctata and Heteronychus arator, others include Brumus quadripustulatus, Chrysolophus spectabilitis, Gynnidomorpha alisman, Componotus pennysylvanicus, Pollistes exclamans,. Reduvius personatus, Mantis religiosa. It was also concluded that the main stage of insect that attack Terminalia ivorensis in this zone is the adult stage and that height as well will determine the species of insect that will attack a particular tree species. It was then recommended that Coccinenids (prediators) should be allowed on Terminalia ivorensis Tree which serves as a biological control of insects and Oecophylla smaragdina (weaver ant) should be allowed to accumulate on Terminalia species as a biological control method.