In vitro Antifungal Activities of Various Plant Crude Extracts and Fractions Against Citrus post-harvest Disease Agent Penicillium digitatum

The aim of the present study is to in vitro evaluate various plant extracts and liquid fractions against citrus post-harvest disease agent Penicillium digitatum. Crude extracts of seven plant materials (fenugreek seeds, harmal seeds, garlic cloves, cinnamon bark, sticky fleabane leaves, and nightshade leaves and fruits). In addition to their methanolic, hexane, and aqueous - fractions were assayed by agar well diffusion and amended agar methods. Regression analysis of results was carried out by using Microsoft Excel and SPSS program. Results indicated that crude extracts of nightshade fruits cinnamon bark have completely inhibited the growth of tested fungal isolates (IC_50 = 57.5 μg ml^(-1), 190-252.5 μg ml^(-1) respectively. Methanolic (except fenugreek), hexane and aqueous fractions of all tested plants have resulted in complete inhibition of tested isolates. The methanolic fraction of cinnamon bark extract has shown the highest antifungal activity as compared with the same fraction from other plants (IC_50 in the range of 5-23 μg ml^(-1 ). Moreover, cinnamon bark hexane fraction was the most effective hexane fraction in all tested plants (IC_50 range: 12.25-14.5 μg ml^(-1 ). Concerning fractions of garlic extract, only methanolic fraction has resulted in complete inhibition of fungal growth (IC50 range: 3.75-18 μg ml-1 ). However, the nightshade leaves aqueous fraction (IC_50 range: 6.75-10.5 μg ml^(-1 ) was the most effective over other fractions of the same plant.