The relationship between uptake and use of resources has always been highlighted among functional traits to explain the performance of invasive and native species. However, previous studies have shown that, under resource limitation, the species of both groups tend to have similar functional behavior. We measured a group of resource-use traits under controlled drought stress in Cenostigma microphyllum native to Caatinga of Brazil and the invasive species Calotropis procera that has a large occurrence in semiarid regions. The results showed that invasive well-watered plants always had higher CO₂ assimilation rates and lower leaf construction costs than native plants, while stomatal conductance was similar. On the other hand, under water deficit conditions, the invasive plants tolerated more days of drought and showed higher root/shoot biomass ratio, leaf relative water content, lower leaf construction costs and payback time than the native species. Moreover, seven days after stress, the invasive plants displayed higher CO₂ assimilation, photosynthetic nitrogen use efficiency, instantaneous efficiency of energy use and lower leaf construction costs compared with the native species. The ability to acquire and distribute resources among the different plant tissues at the right time seems to be a fundamental combination for the plants used in the experiment. Thus, a more acquisitive strategy is fundamental for having enough carbon to invest in the root biomass in C. procera under drought, which could contribute to maintain higher leaf water status for longer time compared with C. microphyllum.

吸收和利用资源之间的关系一直在功能性特征中得到强调，以解释入侵物种和本土物种的表现。但是，先前的研究表明，在资源有限的情况下，两组的物种倾向于具有相似的功能行为。我们在巴西卡廷加（Caatinga）原生的小叶茅（Cenostigma microphyllum）和半干旱地区大量发生的入侵物种Calotropis procera的干旱胁迫下，测量了一组资源利用特征。结果表明，浸水良好的入侵植物总是具有较高的CO ₂含量与天然植物相比，同化率和叶片建造成本更低，而气孔导度相似。另一方面，在缺水条件下，与本地物种相比，入侵植物能够忍受更多的干旱天数，并且显示出更高的根/茎生物量比，叶片相对含水量，更低的叶片建造成本和投资回报时间。此外，胁迫后七天，入侵植物显示出更高的CO _2。与原生物种相比，具有同化作用，光合氮的利用效率，能量的瞬时利用效率和较低的叶片建造成本。在正确的时间在不同植物组织之间获取和分配资源的能力似乎是实验中所用植物的基本组合。因此，一个更贪婪策略是具有足够的碳在根生物量投资于基本C.的Procera干旱条件下，这可能有助于维持相比更长的时间更高叶水状态C. microphyllum。