Effect of Nitrogen Fertilizer Combined with Biochar on the Biomass and Photosynthetic Characteristics of Flue-cured Tobacco/Silage Corn Relay Intercropping on Slope Farmland

• Li WANG, 
• Hao GU, 
• Jialiang LI, 
• Rui YANG, 
• Jun HE, 
• Yi CHEN, 
• Conglian HE, 
• Chenggang HE