The modifying effect of different Bacillus subtilis strains on permeability of pine (Pinus taeda) in two different culture media

One of the main reasons for low treatability of pine wood is pit aspiration during drying in free water domain or heartwood formation. In this research, for opening the aspirated pits in heartwood of loblolly Pine (Pinus taeda), biological incising modification method with bacteria was used and the impacts of different environments and strains of bacteria on the wood gas permeability were studied. Several famous and known strains of Bacillus subtilis UT B96 bacteria in collection of plant protection department of University of Tehran (22, 35, 40, and 96) were supplied in two different culture media of bacteria, namely Nutrient Broth and water bacteria solution. Optical microscopy was used to figure out the qualitative bacterial effect on the tracheid pit pairs. Data analysis revealed that bacteria strain no.22 and water bacteria solution are the most suitable selections to open the aspirated pits and improve the wood permeability. The more destructive effect of the best strain of bacteria may be due to its ability to produce more degrading enzyme. The higher impact of bacteria in the aquatic environment is probably due to their easier mobility, limited access to oxygen or lack of access to an alternative food.