昆明市东川区不同海拔高度水稻生长的差异性分析

Difference Analysis of Rice Growth at Different Altitudes in Dongchuan District of Kunming City

【目的】为深入认识不同生长环境对水稻生长和产量性状的影响。【方法】在昆明市东川区4个不同海拔地点进行籼稻和粳稻盆栽试验。【结果】随海拔高度升高,因有效积温减少、热量强度减弱,水稻孕穗期最大净光合速率和表观量子效率降低、光饱和点和CO2饱和点增大,即光合强度下降;并引起水稻生殖生长后期光饱和点减小,暗呼吸和光呼吸速率及光补偿点增大,即光合效率和光合积累量下降。进而造成茎鞘和叶片干重、叶面积、有效穗数和穗粒数明显下降。【结论】昆明市东川区适宜籼稻和粳稻种植的海拔上限分别为低于1500 m和低于2000 m。较高海拔区低温对籼稻有效穗数、对粳稻穗粒数和有效穗数影响突出。不同海拔高度水稻生长特征指标和产量性状的差异,主要是气温变化而引发水稻光合效应、生长发育变化和低温不利影响的结果。

【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 Dongchuan 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 Dongchuan 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 the 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.