Identification and Evaluation of Resistance to TuMV of Brassica campestris L. ssp. chinensis Germplasm Resources QTL Mapping for TuMV Resistance in Chinese Cabbage [Brassica campestris L. ssp. pekinensis (Lour. ) O lssom] Construction of TuMv Virus-expressing Vector of Green-fluorescent Protein Gene Genetic Transformation of Anti-TuMV-Nib into Transgenic Chinese Cabbages Genetic Transformation of Anti-TuMV-Nib into Transgenic Chinese Cabbages QTL Mapping for TuMV Resistance in Chinese Cabbage [Brassica campestris L. ssp. pekinensis (Lour. ) O lssom] Cloning, sequencing of p3 gene of Turnip mosaic virus isolates in Changchun and preparation of P3 protein antiserum