EFFICACY OF THREE ESSENTIAL OILS AND GARLIC BULBS EXTRACT AGAINST Tetranychus urticae KOCH (Acari: Tetranychidae)
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Abstract
The acaricidal, ovicidal and repellent activity of three essential plant oils viz. neem oil,
black cumin oil, mahagoni oil and garlic bulbs extract were evaluated against
Tetranychus urticae Koch under laboratory condition. The selected oils and extract were
tested at 0.5, 1.0, 1.5, 2.0 and 3% concentration. The results showed that mahagoni oil
acted most efficient acaricidal agent against T. urticae followed by black cumin oil,
neem oil and garlic bulbs extract. The LC50 values of neem oil, black cumin oil,
mahagoni oil and garlic bulbs extracts for adults were 1.070, 1.294, 0.639 and 1.712
respectively and for eggs LC50 values were 1.781 , 1.714, 1.095 and 2.148 respectively.
In persistence test, the mites were exposed to 1, 24, 48 and 72 hours old residue and
found that lethal concentration effects of the plant oils and extracts fade within two or
three days. In the repellents test, mahagoni oil, black cumin oil, neem oil and garlic bulbs
extract showed repellent effects and significantly decreased the number of eggs on
treated bean leaves. Mahagoni oil was found more effective as repellent effects against
adult females of T. urticae followed by black cumin oil, garlic bulbs extract and neem oil
causing reduction in egg production per female by 98.17%, 94.69%, 94.66% and 88.25%
respectively. The results suggest that oils of mahagoni, black cumin, neem and garlic
bulbs extract have the potential to use for the management of T. urticae.