[Effects of transplanting date and density on appearance quality of greenhouse single-flower cut chrysanthemum]. 
Transplanting date and density are the important factors affecting the appearance quality of chrysanthemum.  The study on the greenhouse single-flower cut chrysanthemum (Chrysanthemum morifolium cv.  Shenma) showed that within the ranges of test transplanting date and density, the plant height and neck length increased, while the leaf number per plant, stem diameter, plant fresh mass and flower diameter decreased with the delay of transplanting date and the increase of transplanting density.  No effect of transplanting density was observed on plant height.  For the production of single-flower cut chrysanthemum in non-heated greenhouse in Shanghai, the optimal transplanting date and density to achieve the top rank of quality (rank A) were the middle ten days of August and 64 plants x m(-2), and those to achieve the second rank of quality (rank B) were from mid August to early September and 72-80 plants x m(-2), respectively.  The results obtained in this study offered references in establishing the prediction model of greenhouse single-flower cut chrysanthemum appearance quality based on light, temperature, and transplanting date and density.