Verification of water-use efficiency estimates via carbon isotope discrimination in potato under varying nutrient statuses and CO2 conditions
Verification of water-use efficiency estimates via carbon isotope discrimination in potato under varying nutrient statuses and CO2 conditions
复制标题
通过不同营养状况和二氧化碳条件下马铃薯碳同位素辨别来验证用水效率估计
DOI：
10.1111/ppl.13660
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发表时间：
2022
影响因子：
6.4
通讯作者：
Yan Yi & Katsuya Yano
中科院分区：
文献类型：
--
作者：
Masakaze Imamura;Taiga Kuhara;Daisuke Hamanaka;Yan Yi & Katsuya Yano
升高的CO2（eCO2）有可能增加植物生物量，同时由于提高了水分利用效率（WUE）而降低了对水的需求，这与营养状况相互作用。碳同位素分辨率（Δ 13 C）已被证明是估算WUE的有效替代指标，但在CO2和营养相互作用强烈影响WUE的环境中，其有效性尚不确定。使用一个单一的马铃薯品种（爱尔兰Cobbler），我们研究了其有效性，通过三个独立的试验，不同水平的P，N，或K（试验P，N和K，分别）在生长室在两个CO2浓度。植物水平上的WUE随CO2条件和养分供应速率而变化。在试验P和K中，植物生物量与WUE呈正相关，在试验N中，植物生物量与水分利用呈正相关。在不同的养分供应速率下，WUE与Δ 13 C呈负相关。然而，WUE和Δ 13 C之间的关系随着CO2的增加而改变，增加了沿着y轴（WUE）的截距，而不影响斜率，这意味着呼吸或光呼吸中的同位素歧视。这些结果表明，Δ 13 C不仅可以用于当前CO2条件下的水分利用效率估算，而且可以用于eCO2条件下的水分利用效率估算。
Elevated CO2(eCO2) has the potential to increase plant biomass while decreasing water demand due to enhanced water‐use efficiency (WUE), which interacts with nutritional status. Carbon isotope discrimination (Δ13C) has been shown to be a valid proxy for estimating WUE; however, its validity is uncertain for plants in an environment where the interaction between CO2and nutrition strongly affects WUE. Using a single potato cultivar (Irish Cobbler), we examined its validity through three independent trials with varying levels of P, N, or K (Trial P, N, and K, respectively) in growth chambers at two CO2concentrations. WUE at the plant level varied with CO2conditions and nutrient supply rates. Plant biomass was positively regressed against WUE in Trials P and K, and water use in Trial N. WUE was negatively regressed against Δ13C across various nutrient supply rates within each CO2environment. However, the relationship between WUE and Δ13C was altered with CO2enrichment by elevating the intercept along they‐axis (WUE) without affecting the slope, implying the involvement of isotopic discrimination in respiration or photorespiration. These results suggest that Δ13C can be used to estimate WUE across various nutrient statuses, not only at the current CO2but also at eCO2when the comparisons are made within each CO2condition.