摘要
以盆栽5年生云锦杜鹃苗木为材料,分对照(土壤水分含量为最大田间持水草的75%~80%)、轻度胁迫(60%~65%)、中度胁迫(45%~50%)、重度胁迫(30%~35%)4组,研究了土壤干旱对水分利用效率等生理指标的影响,结果表明:随着干旱胁迫的加重,叶片净光合速率、蒸腾速率、气孔导度依次降低,水分利用效率在轻度胁迫下增高,在重度胁迫下降低.高温使净光合速率降低,蒸腾速率升高,水分利用效率进一步降低。
5-year-old potted Rhododendron fortunei seedlings were used as experiment materials to simulate different soil water statuses, including 4 levels of drought stress: no stress (control), mild stress, moderate stress, severe stress. The resuits showed as follows. Under the condition of temperature of 30 ℃ and photosynthetic active radiation (PAR) of 800μmol · m^-2· s^-1 , with the increases in drought stress, net photosynthetic rate (Pn), transpiration rate (T r) and stomatal conductance (Gs) decreased, while water use efficiency (WUE) increased under mild stress, but became lower under moderate stress and severe stress. Under the condition of 800μmol · m^-2 · s^-1 PAR, the test of photosynthetic response to temperature exhibited an obvious decline of Pn and increase of Tr under higher temperature. There also existed a much decline in WUE under higher temperature.
出处
《河南师范大学学报(自然科学版)》
CAS
CSCD
北大核心
2007年第2期150-153,共4页
Journal of Henan Normal University(Natural Science Edition)
基金
浙江省自然科学基金(Y504256)
浙江省教育厅科研计划资助项目(20030769)
关键词
干旱胁迫
水分利用效率
温度响应
云锦杜鹃
drought stress
water use efficiency
response to temperature
Rhododendron fortunei