Abstract:

Abstract In order to improve the quality of tobacco-leaf in Zhaotong Yunnan, the paper strived to explore the relationships between the climates in tobacco planting and chemical quality of tobacco. Based on numerous observed data related to tobacco quality and meteorological condition, contrast analysis method and Hierarchical clustering method were used to investigate tobacco climates in Yunnan Zhaotong and their influence on chemical quality of tobacco leaf. In this paper, the sorts of chemical quality of tobacco leaves yielded in Zhaotong were objectively compartmentalized. Then the causes that climatic conditions in Zhaotong are suitable to producing tobacco leaves of 4 chemical quality types were probed and finally discovered. And the superiority and defects of tobacco climates in Zhaotong were illustrated. Referring to the gross of three climatic elements (average temperature, rainfall and sunshine duration) during tobacco field-growth season, the tobacco planting area in Zhaotong was always inferior to most other tobacco planting areas in Yunnan and Guizhou province. But it surpassed most tobacco planting areas in Guizhou province in sunshine duration from April to June, and had an advantage over most other tobacco planting areas in Yunnan province in quantity of sunshine and heat from July to August. These climatic characteristics in Zhaotong were advantageous to the formation of its individualized chemical quality for tobacco leaf, which has medium sugar, nitrogen and nicotine but low potassium, still less content of petroleum ether extract (only slightly higher than the one for tobacco in central Yunnan).