Chemical composition, Insecticidal and antifungal activities of Pinus halepensis mill. and Acacia cyanophylla sp. wood tars

Pyrolysis of plant through the rotative oven is a promising and more eco-friendly way to produce charcoal, tar and pyroligneous acid, and other gaseous products with useful purposes. In this research using the Tar of 2 of the most common species in Tunisia Pinus halepensis and Acacia cyanophylla we tried to prove their Insecticidal and fungal activities. For that we started by assessing the Tars' secondary metabolites. Both tars presented important rates but P. halepensis tar presented higher levels of secondary metabolites especially flavonoids with 1.92 mg/ml QE comparing to 1.47 mg/ml QE for A. cyanophylla tar. The antioxidant activity and antioxidant capacity of the 2 tars revealed more pronounced antioxidant activity of P. halepensis tar with 89.5% (%DPPH) and 2.91 mg/ml AAE compared to 75.70% (%DPPH) and 2.72 mg/ml AAE for A. cyanophylla tar. The insecticidal activity against Aphis spiraecola showed faster and stronger efficiency of A. cyanophylla tar extract 25% inducing 73.3% mortality within 2 Hours of exposure and reached 100% mortality after 10H. P. halepensis tar extract 75% showed slower response with 73.3% mortality after 6H of exposure. The results of the antifungal activity of P. halepensis tar extract 10% and A. cyanophylla tar extract 0.75% revealed that P. halepensis tar was more inhibiting of the mycelium growth of many fungi including F.solani, F.nyagami and M.nivale with an inhibition rate of 77% but less effective on other like F.rodelens that reached 77% mycelium growth. On the other hand, cyanophylla tar extract 0.75% was less effective with only 30% inhibition rate of Phoma sp. the other fungi had more than 79% mycelium growth.