关键词: 缓冲容量, 缓冲容量

Abstract: The properties of medium such as peat, vermiculite, carbonized chaff, corn straw in tobacco floating system was summarized in this paper. The physical properties of substituted medium such as soil bulk density, particle size, porosity were evaluated. The chemical properties such as cation exchange capacity, pH and humic acid were discussed. The agronomic traits and physiological-biochemical indexes of tobacco seedlings which reflected biological properties of the medium were described. The effects of inorganic substituted medium such as sand, fly ash and organic substituted medium such as peanut bran, carbonized chaff, corn straw, vermicompost, mushroom residue were summarized. The future development of substituted medium including the screening, the establishment of standards, the addition of microorganism in tobacco breeding system was suggested.