Combination of antibiotics and chitin synthesis inhibitors for the control of Microcerotermes diversus (Isoptera: Termitidae)

Abstract

Abstract The symbiotic microorganisms in the gut of termites play a key role in the digestion of cellulose and nitrogen metabolism. Therefore, disruption of these symbioses activity can open a door toward termite management. Thus, the current study aimed to exploit termite gut bacterial capacity in order to utilize it for efficient termite control. So, in the current study, gut bacteria of Microcerotermes diversus have been extracted, cultivated on both liquid and solid media, and screened with a range of antibiotics to find the most effective antibiotics. Results showed that chloramphenicol and nalidixic acid were the most effective antibiotics in preventing the colony unit formation of the gut bacteria amongst 16 antibiotics tested. Also, from two chitin synthesis inhibitors tested hexaflumuron with an LC50 of 613.9 µg ml−1 was more toxic than lufenuron with an LC50 of 1414.5 µg ml−1. Thus, two antibiotics (chloramphenicol and nalidixic acid) were used simultaneously with a sub-lethal concentration of hexaflumuron against the termite and a variety of factors such as wood consumption rate, running speed, body water content, and tunneling activity were evaluated under laboratory conditions. Results showed that the combination of these two antibiotics (chloramphenicol and nalidixic acid) with hexaflumuron caused a significant decrease in termite consumption rate, running speed, and tunneling behavior, but didn’t affect the body water contents of termites. These results suggest that using a combination of antibiotic/s and hexaflumuron is a promising management practice to get a suitable control measure for the studied termite.