کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
82797 | 158416 | 2008 | 14 صفحه PDF | دانلود رایگان |
Despite the agronomic importance of potato (Solanum tuberosum L.), the interaction of atmospheric carbon dioxide concentration ([CO2]) and drought has not been well studied. Two soil–plant–atmosphere research (SPAR) chamber experiments were conducted concurrently at ambient (370 μmol mol−1) and elevated (740 μmol mol−1) [CO2]. Daily irrigation for each chamber was applied according to a fixed percentage of the water uptake measured for a control chamber for each [CO2] treatment. We monitored diurnal and seasonal canopy photosynthetic (AG) and transpiration rates and organ dry weights at harvest. Plants grown under elevated [CO2] had consistently larger photosynthetic rates through most of the growth season, with the maximum AG at 1600 μmol photons m−2 s−1 14% higher at the well-watered treatments. Water stress influenced ambient [CO2] plants to a larger extent, and reduced maximum canopy AG, growth season duration, and seasonal net carbon assimilation up to 50% of the control in both [CO2] treatments. Water use efficiency increased with water stress, particularly at elevated [CO2], ranging from 4.9 to 9.3 g dry mass L−1. Larger photosynthetic rates for elevated [CO2] resulted in higher seasonal dry mass and radiation use efficiency (RUE) as compared with ambient [CO2] at the same irrigation level. This extra assimilate was partitioned to underground organs, resulting in higher harvest indices. Our findings indicate that increases in potato growth and productivity with elevated [CO2] are consistent over most levels of water stress. This work can support various climate change scenarios that evaluate different management practices with potato.
Journal: Agricultural and Forest Meteorology - Volume 148, Issues 6–7, 30 June 2008, Pages 1109–1122