Determining active area and relationship between yellow sticky traps and absolute population estimates of adult Lixus incanescens L. (Col.: Curculionidae)
Subject Areas :
Keywords: distance, Yellow sticky traps, Sugar beet weevil, Lixus incanenscens,
Abstract :
To determine pest population level and in order to make a proper action decision; proposing a prompt, accurate and reliable sampling technique is the most vital issue in IPM programs.The yellow sticky traps are the most common tools for insect sampling. They are easily and quickly used for trapping tiny flying insects such as small weeviles. Sugare beet weevil (SBW) is one of the most important pests of sugare beet that may sampled by this device. Active area of the traps can affect their performance. Hence determining proper distance between them as well as relationship between absolute estimates and trap counts for SBW were the objectives of the present study. In 2011 and 2012, since mid of spring to mid of autumn, weekly sampling were applied through two approaches of “relative sampling: approximation via yellow sticky traps” and “absolute sampling: number per each plant” in 100 replications. The traps were mounted on wooden stocks at four distances of 1.25, 2.5, 5 and 10 meters from each other in 10, 9, 6 and 3 replications, respectively. One week later, the number of insects captured on one side of each trap was counted. One way ANOVA was used to determine possible differences among traps of each distance and post hoc test of Duncan at both levels of 1 and 5% were used for grouping the treatments. Except for two extraordinary cases, no significant difference was recorded amid traps of each groups and treatments. On the other hand, no obvious relationship was observed between absolute estimates and trap counts. So, a strict statement about active area of the trap for SBW adults and their applicability as a surveying tool of density is impossible and needs the experiments be repeated at higher densities in the future.