Evaluation of Two Mark-Release-Recapture Dyes for Marking Microcerotermes diversus Silvestri (Isoptera:Termitidae )

Mark-Release-Recapture methods are used for delineating foraging territories of termite colonies and estimating their foraging populations. In this research, marking of termites was evaluated by the use of two ingested dyes: Nile Blue (NB) and Neutral Red (NR). In this experiment, filter paper circles were wetted with 1 ml of each dye at concentrations of 0.1%, 0.25% and 0.5% (treatments) and placed into Petri dishes(9.0 cm in diameter), each containing 50 workers (the final stage). In the control treatment, filter papers were moistened with 1 ml of distilled water. Each treatment had four replicates for each dye marker and was kept in a dark incubator (90±5% RH, 28±2˚ C) for one week. The changes in the weight of workers before and after marking were also compared and analyzed using SAS software and means were compared using LSD test. The mean comparison of NB treatments and NR treatments with control through survival, the percentage of stained workers (after Arcsin transformation) and the change in the weight of workers showed that concentrations of 0.1% and 0.25% NB and concentrations 0.25% and 0.5% NR did not show significant differences with control. In order to determine the best concentration for fast marking, in the second experiment, marking was studied after 8h thirsty condition. The termites were stained in one day at concentrations of 0.1% NB and 0.5% NR. Therefore, it is recommended to use concentrations of 0.1% NB and 0.5% NR plus 8h thirsty condition for fast marking. Laboratory experiments and preliminary field studies indicated that dye markers can be used for investigation of M. diversus foraging behavior, determining number of colony, distinguishing nestmates in aggressive behavior experiments and examining the transfer of toxicants between test termites.