Contribution of inflorescences to seed filling have attracted great attention given the resilience of this photosynthetic organ to stressful conditions. However, studies have been almost exclusively focused to small grain cereals. In this study, we aimed to explore these responses in quinoa, as a climate resilient seed crop of elevated economic and nutritious potential. We compared the physiological and metabolic performance of panicles and leaves of two quinoa cultivars growing under contrasting salinity levels. Plant growth, photosynthetic and transpiratory gas exchange and chlorophyll fluorescence were monitored in inflorescences and leaves throughout the experiment. At flowering stage, young and mature leaves and panicles were sampled for key metabolic markers related to carbon, nitrogen and secondary metabolisms. When subjected to salt stress, panicles showed attenuated declines on photosynthesis, water use, pigments, amino acids, and protein levels as compared to leaves. In fact, the assimilation rates, together with a high hexose content evidenced an active photosynthetic role of the panicle under optimal and salt stress conditions. Moreover, we also found significant genotypic variability for physiological and metabolic traits of panicles and leaves, which emphasizes the study of genotype-dependent stress responses at the whole plant level. We conclude that quinoa panicles are less affected by salt stress than leaves, which encourages further research and exploitation of this organ for crop improvement and stress resilience considering the high natural diversity.

鉴于这种光合器官对应激条件的恢复能力，花序对种子灌浆的贡献引起了人们的极大关注。然而，研究几乎完全集中在小粒谷物上。在这项研究中，我们旨在探索藜麦的这些反应，藜麦是一种具有较高经济和营养潜力的气候适应种子作物。我们比较了在不同盐度水平下生长的两个藜麦品种的圆锥花序和叶子的生理和代谢性能。在整个实验过程中，对花序和叶子中的植物生长、光合作用和蒸腾气体交换以及叶绿素荧光进行监测。在开花阶段，对幼嫩和成熟的叶子和圆锥花序进行取样，以获取与碳、氮和次生代谢相关的关键代谢标记物。当遭受盐胁迫时，与叶子相比，圆锥花序的光合作用、水分利用、色素、氨基酸和蛋白质水平的下降有所减弱。事实上，同化率以及高己糖含量证明了穗在最佳条件和盐胁迫条件下具有活跃的光合作用作用。此外，我们还发现穗和叶的生理和代谢性状存在显着的基因型变异，这强调了在整个植物水平上研究基因型依赖性胁迫反应。我们的结论是，藜麦穗受盐胁迫的影响比叶子小，考虑到高度的自然多样性，这鼓励进一步研究和利用这一器官来改善作物和提高抗逆能力。