Bioactlvity of some Essential Oils against the Mediterranean fruit fly (Ceratitis capitata) under Laboratory Condition

Abstract

Mediterranean fruit fly is one of the most important fruit damaging pests. It is a major pest in Ethiopian orchards causing annual loss of about 1,500 tone of orange and mandarin in Upper Awash Agro-Industry Enterprise. Different pest management strategics arc currently employed against the pest and the use o f bio-derived pesticides are known to be widely adopted practical intervention as
major components of integrated pest management (IPM) to tackle the med-fly problems in fruit production. Hence, the bioactivitios of essential oils from local plants were tested against the adult and immature stages o f the fruit fly (C. species). Essential oil bearing local plant materials was collected from Wondo Genet and Addis Ababa areas. Essential oils were produced using hydro-distillation
method using Clavcngcr Apparatus. The repellent action of essential oil of Chenopodiuin ambrosioides. Laggera tomentosa. Schinus /nolle, and Ociinuni suavac were tested against the Mediterranean fruit llics by standard bioassay procedure. The result indicated that more than 90% o f the adult flies were repelled due to application of essential oils on guava fruits in a choice bioassay. Essential oils
extracted from the leaves and succulent parts of O. suavac, showed no significant difference (P> 0.05) in rcpcllency. To determine the prophylactic effects of each essential oil against immature stages (maggots), six levels concentrations (100.150.200,250,300,500 ppm) were studied. Each test preparations were sprayed on pre-infcstcd guava fruits at 12. 24, 36 and 48 hours between infestations
with three replicates for each period. Number of adults emerged from each cage after 21- 30 days were counted and comparison was made with untreated cages to know the efficacy o f the oils. The essential oil extracts caused significant reduction in number of progeny (> 74% mortality) except for extract from O. suave. Thus, products of essential oils both from C. ambrosiodcs and L. tomentosa arc found to be promising against the Mediterranean fruit fly Ccratitis spccics. Hence, the current findings
deserve to be considered as sound inputs for future promotion of detailed practical experiments both under laboratory and field circumstanccs to cnhancc the ongoing Integrated Pest Management Strategy of the country.