Global Change Research Institute CAS, 603 00, Brno, Czech Republic.
Faculty of Science, University of South Bohemia, 37005, České Budějovice, Czech Republic.
Plant Cell Physiol. 2018 Jan 1;59(1):30-43. doi: 10.1093/pcp/pcx144.
Response of rice (Oryza sativa) exposed to both biotic and abiotic stresses can be quantified by employing fast and accurate optical methods. In this study, the overall stress responses of (i) 12 near-isogenic lines (NILs) in the genetic background of the rice blast-susceptible cultivar Lijiangxintuanheigu (LTH) and (ii) four NILs in the genetic background of the bacterial blight-susceptible cultivar IR24, were inspected by means of Chl fluorescence (Chl-F) imaging. The distribution of the maximum and effective quantum yield of PSII (Fv/FM and QY) and steady-state Chl-F (Ft) were found to be effective in differentiating symptomatic leaf tissue for both rice blast and bacterial blight, which correlated well with 30 cycles of rice blast and six cycles of bacterial blight previously screened using classical (manual) approaches. Subsequently, identified Chl-F parameters allowing detection under ambient light (QY and Ft) were tested across both biotic and abiotic (drought) stress experiments, for rice cultivars contrasting for drought stress response (N22, IR64 and NSIC Rc 222). Their applicability has been proven for both rice blast and bacterial blight; however, QY failed to detect the effect of drought. In addition to Chl-F, the usefulness of 11 selected vegetation indices (Vis) was tested on these three cultivars exposed to particular stresses: (i) rice blast was detectable by Vis calculated from the visible spectrum; (ii) bacterial blight by near-infrared-related Vis; and (iii) drought by Vis calculated from the visible spectrum. The key Chl-F parameters and/or Vis have been summarized and discussed.
采用快速准确的光学方法可以定量测定水稻受到生物和非生物胁迫的响应。在这项研究中，通过叶绿素荧光（Chl-F）成像，检测了（i）12 个在水稻白叶枯病敏感品种丽江新团黑谷（LTH）遗传背景下的近等基因系（NILs）和（ii）4 个在细菌性条斑病敏感品种 IR24 遗传背景下的 NILs 的整体胁迫响应。发现最大和有效 PSII 量子产量（Fv/FM 和 QY）和稳态 Chl-F（Ft）的分布能够有效区分水稻白叶枯病和细菌性条斑病的症状叶组织，与之前使用经典（手动）方法筛选的 30 个水稻白叶枯病循环和 6 个细菌性条斑病循环密切相关。随后，在生物和非生物（干旱）胁迫实验中测试了能够在环境光下检测到的鉴定出的 Chl-F 参数（QY 和 Ft），这些实验涉及对干旱胁迫反应不同的水稻品种（N22、IR64 和 NSIC Rc 222）。结果证明，这些参数既适用于水稻白叶枯病，也适用于细菌性条斑病；然而，QY 无法检测到干旱的影响。除了 Chl-F，还在这三个品种上测试了 11 种选定的植被指数（Vis）在特定胁迫下的有效性：（i）通过计算可见光谱的 Vis 可以检测到水稻白叶枯病；（ii）通过近红外相关 Vis 检测到细菌性条斑病；（iii）通过计算可见光谱的 Vis 检测到干旱。总结并讨论了关键的 Chl-F 参数和/或 Vis。
