COMBINATION EFFECTS OF BIOCHAR AND EFFECTIVE MICROORGANISMS ON GROWTH AND PHOTOSYNTHETIC INDEXES OF FLUE-CURED TOBACCO

Due to long-term continuous cropping and over use of chemical fertilizers, it has restricted the growth of flue-cured tobacco seriously, and which caused the decreasing yield and quality of tobacco leaves. Different biochar combined with effective microorganisms (EM) treatments were designed to explore the influences on the growth of flue-cured tobacco in the pot experiment. The results showed that the leaf area index (LAI) of BlE1 (1.5% biochar combined with 1.5% EM) was the largest (3.89), which increased 28.53% more than that of CK. The biochar and EM application have significantly increased net photosynthetic rate (Pn), stomatal conductance (Gs) and intercellular CO2 concentration (Ci), and decreased transpiration rate (Tr). The yield of B1E1 was the highest (2546.61 kg.hm(-2)), which have a significant difference with other treatments (P<0.05), and it has increased more than 33.6% and 25.83% compared with B2E2 (2.5% biochar combined with 2.5% EM) and CK. Therefore, appropriate amount of biochar combined with EM application have a significantly effect on the growth of flue cured tobacco, but the excessive biochar and EM will inhibit it, BlE1 is the best coupling treatments, and the results could provide theoretical and practical guidance for the growth of crop.