Effect of combinatorial essential oil ingredients of Citrus maxima on percent wood weight loss and infestation caused by Indian white termite Odontotermes obesus

Abstract

In the present investigation, various field bioassays were performed to evaluate the anti-termite efficacy of Citrus
maxima essential oil-based combinatorial formulations against Indian white termite. LD50 values of various
formulations were found in the range of 12.73–702.489 μg/g. In subsequent bioassays, crude essential oils and
combinatorial mixtures have shown high toxicity against Odontotermes obesus. LD50 was obtained in the range
of 702.489 μg/g for S-RET-C against O. obesus. Active ingredients present C. maxima essential oil repel and
kill termites in thread binding assays, poison baits, and direct spray in field and garden saplings. Combinatorial
mixtures of Citrus essential oils have shown synergistic activity against termites. Bait formulation (0.125% w/v)
was also used which significantly cut down infestation of crop field termite in various crop fields. Combinatorial
mixtures S-RET-B repelled (80%) termites to the opposite arm in Y-shaped tube. Besides this, C. maxima extracts
have shown significant reduction (89%) in termite infestation in garden saplings. These combinatorial mixtures
were also used for wood seasoning of solid wood sticks and hollow wood sticks which gave very good results as test
wood sticks have shown significantly 70–80% reductions in termite infestation. C. maxima combinatorial mixtures
displayed significant protection to garden saplings and resisted against wood invasion in field experiments. These
gave an overall sustainable way to termite control in crop field mainly maize and millet crops.