Research on Variation of Stem-leaf Angle and Leaf's SPAD during the Maturity Period of Flue-cured Tobacco under Different Fertilizer Levels

• WANG Na, 
• ZHAN Enneng, 
• LI Zhonghuan, 
• YANG Zhengquan, 
• DENG Qiao, 
• QIN Chunli, 
• FANG Zhengfen, 
• ZHAO Zhengxiong, 
• JIAO Yuhang, 
• LU Hong