Potassium (K) and phosphorus (P) are essential macronutrients for potato (Solanum tuberosum L.); they play crucial roles in photoassimilate production that can also be affected by elevated atmospheric CO₂ concentration (e[CO₂]). However, the interactive effects of K and P nutrition under e[CO₂] in potato have not been investigated. A pot experiment was carried out on potato plants in 1-L pots with five K supply rates at two P supply rates in controlled-environment chambers with ambient CO₂ concentrations (a[CO₂]) and an e[CO₂] level of double a[CO₂]. There was a significant interaction between K supply and P supply, but not between CO₂ and K supply on total plant biomass, water use as well as water-use efficiency (WUE). K supply could remarkably enhance the accumulation of plant biomass under e[CO₂] by promoting tuber formation. The maximum total plant biomass increased by approximately 1.3-fold under e[CO₂] in this study, while the effect of CO₂ was dependent on both P and K supply. Additionally, WUE was increased by e[CO₂] and P and K supply. Both CO₂ enrichment and K supply increased WUE by stimulating biomass accumulation and reducing water consumption. We concluded that the CO₂-fertilization effect and WUE were dependent on both P and K supply. Less biomass accumulation in response to K supply in plants with P deficiency indicates that a balanced nutrient status is crucial for crop production under e[CO₂].

中文翻译：

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马铃薯加倍 CO2 的植物生长和水分经济：钾和磷的相互作用

钾 (K) 和磷 (P) 是马铃薯 ( Solanum tuberosum L.) 的必需常量营养素；它们在光同化物生产中起着至关重要的作用，而光同化物生产也可能受到大气 CO ₂浓度 (e[CO ₂ ])升高的影响。然而，马铃薯中e[CO ₂ ]下钾和磷营养的交互作用尚未得到研究。在具有环境 CO ₂浓度 (a[CO ₂ ]) 和 e[CO ₂ ] 水平的受控环境室中，在具有五个 K 供应速率和两个 P 供应速率的 1-L 盆中对马铃薯植株进行盆栽试验。双a[CO ₂]。钾供应和磷供应之间存在显着的相互作用，但 CO ₂和钾供应之间对植物总生物量、用水和用水效率 (WUE)没有显着的相互作用。钾供应可以通过促进块茎形成显着增强e[CO ₂ ]下植物生物量的积累。在本研究中，在 e[CO ₂ ]下，最大植物总生物量增加了约 1.3 倍，而 CO ₂的影响取决于 P 和 K 供应。此外，WUE 因 e[CO ₂ ] 和 P 和 K 供应而增加。CO ₂富集和钾供应都通过刺激生物量积累和减少水消耗来增加WUE。我们得出结论，CO ₂- 施肥效应和 WUE 取决于 P 和 K 供应。磷缺乏植物响应钾供应的较少生物量积累表明平衡的营养状态对于e[CO ₂ ]下的作物生产至关重要。