Efficacy test of Melaleuca leucadendra and Callistemon viminalis essential oils on in vitro control of a strain of Aspergillus flavus isolated from peanut seeds in Senegal

Abstract

This study consists of an efficacy test of essential oils of two plant species of the Myrtacae family (Melaleuca
leucadendra and Callistemon viminalis) on the in vitro control of a strain of Aspergillus flavus potentially
aflatoxinogen isolated from peanut seeds in Senegal. To do this, different doses (750, 500, 250 and 100 ppm) of
each oil were associated with the culture medium Czapek Yeast Extract Agar (CYA) and the development of the
strain on the different culture media was followed for 7 days, after which the mycelial growth (mean colony
diameter) and the sporulation density (average number of conidia per mm2) were evaluated in the 4 repetitions
of each treatment. The results showed that C. viminalis essential oil at the higher dose of 750 ppm (T5) was
found to be more effective, just after Mancozeb at 500 ppm (T9) used as the reference control, with no
significant difference. This T5 was closely followed by the T6 (Callistemon 500 ppm), T1 (Melaleuca 750 ppm)
and T2 (Melaleuca 500 ppm) treatments on the inhibition of fungus growth and reproduction.