Effects of Sunlight Radiation on the Production of Quality Winter-Spring Oriental Tobacco in Yunnan Province
In the years of 2001 and 2002, the experimentation of different oriental tobacco population densities and the climate investigation were carried out in Luoming and Kejie regions, two of the staple production bases of the winter-spring oriental tobacco in Yunnan Province. The results indicated the climatic characteristics of the variation of the maximum and the minimum temperature, the average atmospheric temperature, and of the earth temperature etc in the oriental tobacco-growing season. The ten-day average earth temperatures in December and January were 0.5℃ ~ 3.0℃ higher than the atmospheric temperatures in this period. The minimum atmospheric temperature was 3.0℃ ~ 3.4℃ and varied in different periods and locations. The effect of plant density on the rapid growing days, dry-matter accumulation, yields and leaf quality varied with the different climate type. The optimum plant population density is 40cm × 12cm, and the dry weight of the stem of a single plant is about 28.44g ~ 31.33g, the leaves 82.99g~ 91.41 g, the yield is 1 729. 1kg ~ 1 903.8kg/hm2 . The weak sunlight radiation in the winter of the two areas restricted the production of quality tobacco leaves. Leaf quality and yield in the northern tropical zone were better than those in the southern subtropical zone. Higher value of STg-d resulted in better sugar content (16.68%) and higher temperature in 10cm depth of earth resulted in higher level of nicotine content (0.49%). The mathematical model of Plant Height-Temperature was constructed: y' = c0+ a∑i=1 ci· xi.The factors restricting plant height development are the minimum atmospheric temperature in the northern tropical zone and the maximum atmospheric temperature in the southern subtropical zone. Consequently, the agro-biological light and sunlight radiation intensity can be used to judge the effects of heat conditions on the growth of oriental tobacco in different planting regions. The formula was: ST = 1/2 n n∑ i=1 Ti·n ∑ i=1 Si. Some proposals for quality oriental tobacco production are: l) the lower atmospheric temperature in December and January is harmful to the wintertime oriental tobacco production. Therefore, the low altitude areas are not suitable for oriental tobacco planting; 2) Measures for increasing the soil temperature in winter should be taken; 3) The northern tropic zone is more suitable for wintertime oriental tobacco production; 4) Different field management procedures should be considered in the regions of different climate type.
Climatic heat conditionsQuality oriental tobaccoLeaf dry weightChemical componentsPlant height-temperature model
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万方数据
维普
