Abstract：To explore the effects of two cultivation measures of double ridge tillage and straw returning as well as their interaction on soil nutrients and tobacco yield and quality, the flue-cured tobacco variety K326 was used as the experimental material, and a field trial with randomized block design was conducted in a flue-cured tobacco planting area in Yizhang County, Hunan Province, based on two kinds of ridge tillage methods (one is one-time ridge tillage, and the other is the first ridge tillage followed by soil exposure to sun-light, and then the second ridge tillage) and whether rice straw returns to field or not. The results showed that, compared with one-time ridge tillage (T1+T2) and no straw returning (T1+T3), the double ridge tillage (T3+T4) and straw returning (T2+T4) significantly increased soil organic matter content, and improved the sugar-nicotine and nitrogen-nicotine ratios of tobacco leaves as well as the tobacco yield, output value and productivity. The positive interaction between double ridge tillage and straw returning was significant. In ad-dition, the double ridge tillage also significantly raised the total sugar and reducing sugar contents of tobacco leaves, and significantly lowered the nicotine content, leading to more suitable sugar-nicotine and nitrogen-nicotine ratios. In terms of sensory evaluation, rice straw returning could significantly improve the sensory quality of tobacco leaves. Due to a higher production cost resulted from double ridge tillage, for the sandy soil with good basic fertility, one-time ridge tillage combined with rice straw returning could achieve better economic returns. The study provides scientific evidence for better cultivation of flue-cured tobacco in to-bacco-rice rotation areas in Hunan Province.
