The Effect Of Plastic-mulching Cultivation Measures On The Soil Environment, Growth, Leaf Yield And Quality Of Flue-cured Tobacco Of Chuxiong

Field experiment was carried in Chuxiong state, Yunnan province in 2007. To study the effect of several agronomic measures, such as plastic-mulching, ridge height, transplant-watering and organic fertilizer, on the tobacco growth, leaf yield and value, soil environment, the orthogonal experiment was selected and conducted. The result are as follows:1. The plastic-mulching measures could increase the soil temperature obviously. The soil temperature in plastic-mulching field was 5 V higher than that in unplastic-mulching field. The effect was not identical at the whole growing period. The soil temperature increased greatly under the plastic-mulching measures before the vigorous growing stage, but not after that stage.2. Unplastic-mulching and higher ridge could maintain the humidity of soil. Upon the transplanting day, plastic-mulching and watering 2kg/plant water would benefit for maintaining the water content in soil, while unplastic-mulching wound do the same effect for the later growing period. As for the soil bulk density, the most effective factors was plastic-mulching measures on 55 d after transplanting and ridge height after harvest. The results suggested that plastic-mulching and higher ridge wound increase the soil bulk density and that wound baden the soil porosity and aeration. Therefore, removing the plastic after plastic-mulching at a reasonable stage and selecting suitable ridge height in practice were very important.3. Plastic-mulching could made the tobacco grow faster during the root extending stage, but removing plastic measures wound benefit for the root growing during the vigorous growing and budding stage. The root volume and biomass increased with the ridge height and watering amount.4. The ridge height, transplant-watering and organic fertilizer did not affect the growing period of flue-cured tobacco, but the plastic-mulching measures. The total growing period for plastic-mulching field was 6 days shorter than that of the removing plastic treatment.5. Before harvest, both plastic-mulching and removing plastic measures could promote the plant height. The leaf area was largest under removing plastic treatment, while that was least under the unplastic-mulching treatment. However, there was reversed result for the biomass per plant.6. Plastic-mulching could made the most effective on leaf yield, value, average price per kilogram and ratio of high-rate leaves. The values of these four economic factors: leaf yield, yield value, average price and ratio of high-rate leaves were higher under plastic-mulching treatment and removing plastic treatment than unplastic-mulching treatment.