Studies on optimal temperature and time to treat corn stalk by Pleurotus ostreatus Effects of Pulsed Magnetic Field on the Biochemical and Physiological Characters and Ultrastructure of Pine Wood Nematode Relationship Between Cellulase Secreted by Microdochium bolleyi and Total Organic Matter Degradation of Two Kinds of Lawn Grass Litter Optimization of Submerged Culture Requirements for the Cellulase Activity by Phlebiopsis gigantea and Screening the Most Effective Strain Ultrastructural Localization of Cellulase Acitvity in Lytic Root Cortical Cells during Aerenchyma Formation of Flooded Maize