Background Over the past decades, the structural and functional genomics of rice have been deeply studied, and high density of molecular genetic markers have been developed. However, the genetic variation in leaf photosynthesis, the most important trait for rice yield improvement, was rarely studied. The lack of photosynthesis phenotyping tools is one of the bottlenecks, as traditional direct photosynthesis measurements are very low-throughput, and recently developed high-throughput methods are indirect measurements. Hence, there is an urgent need for a fast, accurate and direct measurement approach. Result We reported a fast photosynthesis measurement (FPM) method for phenotyping photosynthetic capacity of rice, which measures photosynthesis of excised tillers in environment-controlled lab conditions. The light response curves measured using FPM approach coped well with that the curves measured using traditional gas exchange approach. Importantly, the FPM technique achieved an average throughput of 5.4 light response curves per hour, which was 3 times faster than the 1.8 light response curves per hour using the traditional method. Tillers sampled at early morning had the highest photosynthesis, stomatal conductance and the lowest variability. In addition, even 12 h after sampling, there was no significant difference of photosynthesis rate between excised tillers and in situ. We finally investigated the genetic variations of photosynthetic traits across 568 F2 lines using the FPM technique and discussed the logistics of screening several hundred samples per day per instrumental unit using FPM to generate a wealth of photosynthetic phenotypic data, which might help to improve the selection power in large populations of rice with the ultimate aim of improving yield through improved photosynthesis. Conclusions Here we developed a high-throughput method that can measure the rice leaf photosynthetic capacity approximately 10 times faster than traditional gas exchange approaches. Importantly, this method can overcome measurement errors caused by environmental heterogeneity under field conditions, and it is possible to measure 12 or more hours per day under lab conditions.

中文翻译：

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用于表型分析水稻光合能力的快速光合作用测量。

背景在过去的几十年里，水稻的结构和功能基因组学得到了深入的研究，并开发了高密度的分子遗传标记。然而，叶片光合作用的遗传变异是水稻增产最重要的性状，却很少被研究。缺乏光合作用表型工具是瓶颈之一，因为传统的直接光合作用测量的通量非常低，而最近开发的高通量方法是间接测量。因此，迫切需要一种快速、准确和直接的测量方法。结果 我们报道了一种快速光合作用测量 (FPM) 方法，用于对水稻光合能力进行表型分析，该方法在环境控制的实验室条件下测量离体分蘖的光合作用。FPM法测得的光响应曲线与传统气体交换法测得的光响应曲线吻合较好。重要的是，FPM 技术实现了每小时 5.4 条光响应曲线的平均吞吐量，这比使用传统方法每小时 1.8 条光响应曲线快 3 倍。在清晨取样的分蘖具有最高的光合作用、气孔导度和最低的变异性。此外，即使在取样后 12 小时，离体分蘖与原地之间的光合速率也没有显着差异。我们最终使用 FPM 技术研究了 568 个 F2 系的光合性状的遗传变异，并讨论了使用 FPM 每天每个仪器单位筛选数百个样品以生成大量光合表型数据的逻辑，这可能有助于提高选择能力在大量水稻种群中，最终目的是通过改善光合作用来提高产量。结论 在这里，我们开发了一种高通量方法，可以比传统的气体交换方法快约 10 倍地测量稻叶光合能力。重要的是，这种方法可以克服野外条件下环境异质性造成的测量误差，在实验室条件下每天可以测量12小时或更多小时。这可能有助于提高大量水稻群体的选择能力，最终目的是通过改善光合作用来提高产量。结论 在这里，我们开发了一种高通量方法，可以比传统的气体交换方法快约 10 倍地测量稻叶光合能力。重要的是，这种方法可以克服野外条件下环境异质性造成的测量误差，在实验室条件下每天可以测量12小时或更多小时。这可能有助于提高大量水稻群体的选择能力，最终目的是通过改善光合作用来提高产量。结论 在这里，我们开发了一种高通量方法，可以比传统的气体交换方法快约 10 倍地测量稻叶光合能力。重要的是，这种方法可以克服野外条件下环境异质性造成的测量误差，在实验室条件下每天可以测量12小时或更多小时。