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[Objective] The purpose of the paper is to further understand the effects of different growth environments on the growth and yield characteristics of rice. [Method] Two varieties, indica and japonica rice, were selected and pot cultured to test at four different altitudes in Dongehuan District of Kunming City. [ Result] With the increase of planting altitude, the effective accumulated temperature of rice decreased and the heat intensity decreased, resulting in the decline of maximum net photosynthetic rate and apparent quantum efficiency and the increase of light saturation point and CO2 saturation point during the booting stage of rice, which meant the weakening of photosynthetic intensity in vigorous grow stage. Meanwhile, the photosynthetic efficiency and photosynthetic accumulation of rice decreased during the later period of rice reproductive stage because of the decrease of photosaturation point, dark respiration rate, photorespiration rate and photosynthetic compensation point. Then the dry matter of leaf and stem sheath ,leaf area, the number of effective panicles and effective grains per spike were significantly reduced. [Conclusion] The upper limit of suitable altitudes for indica rice and japonica rice in Dongehuan District of Kunming City were lower than 1500 meters and 2000 meters respectively. Cold injury had significant effects on the effective-panicles number of indica rice, the effective-grains number and effective-panicles number of japonica rice. The differences of rice growth characteristics and yield traits among different planting altitudes were mainly ascribed to tiny photosynthetic physiological effects of rice, the growth and development change of rice resulting from the disparity of air temperature and the adverse effect of low temperature. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to provide theoretical basis for the rational application of potassium and chlorine fertilizer in the flue-cured tobacco production in Yunnan raw material base of Yunyan brand.【Method】 1130 soil samples from 37 counties of Kunming, Qujing, Honghe, Baoshan, Wenshan were used as materials to determine the content of potassium and chlorine in tobacco samples. The characteristics of potassium and chlorine ratio in different regions, main varieties, soils at different altitudes and tobacco leaves in Yunnan raw material base of Yunyan brand were analyzed. The potassium chlorine ratio of tobacco leaves was regionalized by ArcGIS. 【Result】The results showed that the samples with potassium chloride ratio more than 10 % were the most, accounting for 43.2 %; The samples with potassium chloride ratio between 4.0 % and 6.0 % were the least, accounting for 11.7 %. Qujing had the largest number of towns with low K/C ratio(< 4 %) and Wenshan had the smallest; Qujing had the largest number of towns with high K/C ratio(> 10 %), while other cities had the same number. The main cultivar with the highest mean of K/C ratio in middle tobacco leaves was Yunyan 85, which was 14.41; The lowest was Yunyan 97, which was 7.30; The others were between 8.44 and 12.73. The highest mean of K/C ratio of middle tobacco leaves in different altitude areas was 11.72, which was mainly distributed in the altitude area of 1100-1400 meters; The lowest was 8.91, which was mainly distributed in the altitude area of 2000-2300 meters. 【Conclusion】In order to production of high-quality flue-cured tobacco in Yunnan raw material base of Yunyan brand, areas with high K/C ratio of tobacco leaves in Kunming, Qujing, Honghe, Baoshan and Wenshan could be selected. K326, Yunyan 87, Yunyan 85 and other high efficient flue-cured tobacco varieties for potassium accumulation and utilization could be selected. It could be planted at the altitude of 1100-2000 meters. [ABSTRACT FROM AUTHOR]