作　　者： ; ; ; ; ; ;

机构地区： 中国气象局兰州干旱气象研究所

出　　处： 《生态学报》 2008年第4期1646-1654,共9页

摘　　要： 针对作物水分胁迫较为严重的西北半干旱区,应用CI301-PS光合作用仪对春小麦开花到乳熟期间的生理特征和环境因子进行了近1个月的观测,并研究分析了3种作物干旱指标叶水势、作物水分胁迫指数以及气孔导度随时间变化和对气象因子的响应。发现干旱胁迫增加时,叶片水分减少,作物水分胁迫指数增大,叶水势降低,气孔导度有所减小。因此,气孔下腔的CO2浓度降低,作物净光合速率有所减小,不利于半干旱区小麦生物量的累积;三者相比,叶水势是反应西北半干旱区作物干旱最敏感的指标;受半干旱区逆湿现象的影响,9:00或之后一段时间观测叶水势和气孔导度对小麦等作物缺水状况反映得更客观。 Aimed at severe crop water stress over semi-arid region in Northwest China, Some physiological and environmental parameters are observed during the Spring wheat＇ s flowering and ripe period by CI301-PS photosynthesis instrument,the observation lasts for 1 month, based on the observed value, crop water stress index （CWSI） is calculated, and leaf water potential （LWP） is evaluated. The variations of CWSI, LWP and stomatic conduction with the time and climate change are analyzed. The results show that with the increase of water stress, leaf water will decrease, and CWSI will increase, and leaf water potential will decrease, and stomatic conduction will decrease. As a result, CO2concentration entering stomata will reduce, and the crop net photosynthesis ratio will decrease, and all of these go against biomass accumulation. By Comparison with these three indexes, it is found that CWSI is the worst index responsing to climate change and crop drought, leaf water potential is better than the stomatic conduction. Because of the reverse humidity in the arid regions, it is the most suitable time to observe leaf water potential and stomatic conduction at 9：00 AM. or after 9：00 AM.

关 键 词： 作物水分胁迫指数 气孔导度 叶水势 干旱 蒸腾速率

领　　域： [生物学]