Abstract:There are more and more concerning on application of biochar in agriculture. Aiming to avoid excessive use of peat resource and explore its substitute, a pepper seeding experiment in the greenhouse was carried out. Three biochars (pyrolysised in 350℃, herb residue biochar, sawdust biochar and pig manure biochar as follow) were selected to be mixed with vinegar residue as the organic substrate, vermiculite and perlite as the inorganic substrate, and then those materials were mixed at four ratios to study their effects on the growth of pepper seedlings with peat substrate as control. After mixed with vinegar residue at different ratios, the pH and air filled porosity of biochar substrate became more appropriate for seeding. As a whole, the treatments containing 20% biochar showed better in height, stem diameter, leaf area, ground biomass of pepper seedlings, the treatments including 20% and 40% herb residue showed better in root surface and root volume while showed no significant difference with the control in short term, but better significantly than peat substrate in later period. The seedling index of treatments (B1A2(herb residue biochar︰vinegar residue︰vermiculite︰perlite=4︰2︰3︰1), B1A4(herb residue biochar︰ vinegar residue︰vermiculite︰perlite=2︰4︰3︰1), B2A4(sawdust biochar︰vinegar residue︰vermiculite︰perlite = 2︰4︰3︰1)) were higher significantly than other treatments. Considering the multiple growth indicators of pepper seedling, the treatments B1A2 and B1A4 performed best among all treatments. So it is concluded that the two substates can replace peat for the pepper seedlings growth.