Abstract: In order to study the effects of one-time fertilization of slow-controlled-release nitrogen and potassium fertilizer on tobacco growth, three treatments with equal nutrient inputs were set up in loam soil and sandy soil, respectively, which were CF(conventional fertilizer), T1(slow-controlled-release nitrogen and potassium fertilizer), and T2(slow-controlled-release nitrogen and potassium fertilizer + seedling-raising fertilizer). The results showed that, there was no obvious difference in the agronomic traits of tobacco in T1 and T2 compared with CF. The photosynthesis of tobacco had presented similar results. At the maturing stage, there was no significant difference in the biomass of tobacco among T1, T2 and CF in loam soil. However, in sandy soils, application of slow and controlled release nitrogen and potassium fertilizers reduced the biomass of lower leaves of tobacco. Though the frequency of fertilization reduced, T1 and T2 had showed the same or more positive impact on the root growth of tobacco compared with CF, which ensured the absorption of nitrogen, phosphorus and potassium by tobacco, and ultimately ensured the growth of tobacco. Overall, the application of slow and controlled release nitrogen and potassium fertilizers had ensured tobacco growth while reducing the frequency of fertilization in loam soil, but in sandy soil, the amount of application of slow and controlled release nitrogen and potassium fertilizers should be increased compared to CF. Changing multiple fertilization to one-time fertilization by using slow-release nitrogen and potassium fertilizer could save the labor and time cost for tobacco farmers, while ensuring the normal growth of tobacco. It suggested a simplified cultivation method for tobacco.

Key words: tobacco, slow-controlled-release nitrogen and potassium fertilizer, loam soil, sandy soil