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【Objective】This paper aimed to provide a theoretical basis for rational planting of tobacco in Guizhou yellow soil. 【Method】A field experiment was conducted with two plant patterns of rotation and continuous cropping in Zunyi city in the year of 2016 and 2017, and total amount of nitrogen, phosphorus and potassium were consistent within a rotation period. Root morphology, yield and nutrient utilization of rotation and continuous were determined and soil nutrition was analyzed after flue-cured tobacco harvested. 【Result】Compared with continuous cropping of tobacco, root length, total surface area, total volume was obviously increased by 5601.1 cm, 1976.3 cm2 and 59.17 cm3 under rotation cropping of rice and tobacco, the average diamond was decreased by 0.17 cm. The yield and output of tobacco of the continuous pattern were 1098 kg·hm-2 and 28 548 yuan·hm-22, respectively, lower than that under the rotation cropping pattern. The absorption of N and K under rotation cropping were higher than continuous cropping. Soil pH at 0-20 and 20-40 cm were decreased after crop harvested, and the soil alkali hydrolyzable nitrogen, available phosphorus, available potassium, nitrate nitrogen and ammonium nitrogen were increased in continuous cropping of tobacco. 【Conclusion】The nutrients uptake, yield and economic benefits of tobacco under rotation of rice and tobacco were better than continuous cropping of tobacco, so we should pay attention to the rotation of tobacco and rice or other crops to increase yield and output, thus to promote sustainable development of tobacco industry. [ABSTRACT FROM AUTHOR]

[Objective] The effects of commercial organic fertilizer as the substitution of 20% chemical fertilizer on the growth, yield of spring maize and the soil fertility are explored, which provides reference for enhancing effect and reducing fertilizer application amount of maize in Guizhou. [Method] Taking Jingfeng 8 as the test material, the fertilization experiments of field-grown maize with cover film are implemented with conventional chemical fertilizer ( treatment 1, CK),80% nitrogen fertilizer + 3000 kg/hm² commercial organic fertilizer (treatment 2) and 80% nitrogen fertilizer + 4500 kg/hm2 commercial organic fertilizer( treatment 3) . [ Result] The yield of treatment 3 was the highest, which increases by 6. 83 % compared with treatment 1, and reached to the significant level. There were little differences in spike length, spike number and barren ear tip with different treatment, but treatment 3 owns the thickest spike (54.46 mm),the shortest barren ear tip (0. 83 cm) and the most kernel number per row (40). The plant height, stem diameter and ear height of treatment 2 was the best, which was obviously better than other treatments. The absorption amount of N, P and K in the stem of treatment 3 was the highest, which increases 3.33 %, 3. 06% and 1. 50% respectively compared with treatment 1,and increases by 5. 54%,6. 93% and 3. 70% respectively compared with treatment 2. The pH of treatment 3 was bigger than other treatments, and the total nitrogen and alkaline-hydrolysis nitrogen content was the highest too. [Conclusion] Commercial organic fertilizer as the substitution of 20% nitrogen fertilizer is beneficial for the growth, yield of spring maize, and fertility improvement. The stable yield of corn can be realized when 3000 kg/hm² commercial organic fertilizer is substituted for 20% nitrogen fertilizer. The yield, yield composition, total nitrogen and alkaline-hydrolysis nitrogen content are the best, and the soil acid improvement is better when 4500 kg/hm² commercial organic fertilizer is substituted for 20% nitrogen fertilizer. 4500 kg/hm² commercial organic fertilizer is recommended in substituting 20% nitrogen fertilizer for spring maize in Guizhou. [ABSTRACT FROM AUTHOR]