Predicted increases in atmospheric concentration of carbon dioxide (CO2 ) coupled with increased temperatures and drought are expected to strongly influence the development of most of the plant species in the world, especially in areas with high risk of desertification like the Mediterranean basin. Helianthemum almeriense is an ecologically important Mediterranean shrub with an added interest because it serves as the host for the Terfezia claveryi mycorrhizal fungus, which is a desert truffle with increasingly commercial interest. Although both plant and fungi are known to be well adapted to dry conditions, it is still uncertain how the increase in atmospheric CO2 will influences them. In this article we have addressed the physiological responses of H. almeriense × T. claveryi mycorrhizal plants to increases in atmospheric CO2 coupled with drought and high vapor pressure deficit. This work reports one of the few estimations of mesophyll conductance in a drought deciduous Mediterranean shrub and evaluated its role in photosynthesis limitation. High atmospheric CO2 concentrations help desert truffle mycorrhizal plants to cope with the adverse effects of progressive drought during Mediterranean springs by improving carbon net assimilation, intrinsic water use efficiency and dispersal of the species through increased flowering events.

中文翻译：

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大气CO 2 升高改变了地中海沙漠松露菌根灌木对水分胁迫和开花的响应

预计大气中二氧化碳 (CO2) 浓度的增加以及气温升高和干旱将强烈影响世界上大多数植物物种的发展，特别是在地中海盆地等荒漠化风险高的地区。Helianthemum almeriense 是一种具有重要生态意义的地中海灌木，具有额外的兴趣，因为它是 Terfezia claveryi 菌根真菌的宿主，这是一种具有越来越多商业价值的沙漠松露。尽管已知植物和真菌都很好地适应了干燥条件，但仍不确定大气 CO2 的增加将如何影响它们。在本文中，我们讨论了 H. almeriense × T. 的生理反应。claveryi 菌根植物增加大气 CO2 加上干旱和高蒸气压不足。这项工作报告了对干旱落叶地中海灌木叶肉电导的少数估计之一，并评估了其在光合作用限制中的作用。大气中高浓度的二氧化碳有助于沙漠松露菌根植物通过增加开花事件来改善碳净同化、内在水分利用效率和物种扩散，从而应对地中海春季逐渐干旱的不利影响。