Y. Sarrafi; Gh.R. Moradi Robati; M.H. Fatemi
Abstract
The objective of this study was to investigate the antifungal effects of liquid smoke from tobacco waste on three plant pathogenic fungi and identification and measurement of compounds effective on the antifungal properties of liquid smoke. The waste was pyrolyzed in furnace in the absence of oxygen, ...
Read More
The objective of this study was to investigate the antifungal effects of liquid smoke from tobacco waste on three plant pathogenic fungi and identification and measurement of compounds effective on the antifungal properties of liquid smoke. The waste was pyrolyzed in furnace in the absence of oxygen, and smoke was converted to liquid smoke by refrigerant. Antifungal effects of liquid smoke were tested against Sclerotinia sclerotiorum, Rhizoctonia solani and Phytophthora nicotianae causing tobacco sore shin, collar rot and black shank disease agents, respectively. Six concentrations of the liquid smoke 0, 250, 500, 1000, 2000 and 4000 ppm were prepared and mixed with culture medium. The results of variance analysis showed that the effect of liquid smoke, concentration and the interaction of liquid smoke on concentration in limiting the fungal growth were significant at 1% probability level. Mean comparison of the effect of liquid smoke on these fungi showed that liquid smoke of 25% midrib + 75% scrap pyrolysis in 4000 ppm concentration had 100 percent mycelial growth control on the above fungi. In addition, the liquid smoke pyrolysis of above treatment in low concentrations caused 100 percent mycelia growth control of Rhizoctonia and Sclerotinia. According to research reports, the presence of phenolic compounds, organic acids and alkaloids constituents in liquid smoke is an agent of antifungal effects. Therefore, extraction of these constituents from liquid smoke was carried out and qualitative analysis was done by gas chromatography and mass spectrometry (GC/MS) and quantitative analysis of total phenol and alkaloids was done by spectrophotometer method. The results of this research showed that the effects of alkaloids constituents on the control of fungi were more than phenolic and organic acids constituents in liquid smoke from tobacco waste. The results showed the high potential of the liquid smoke of pyrolysis to be used as a biological control of pathogenic fungi.