Seed osmopriming invokes stress memory against post-germinative drought stress in wheat (Triticum aestivum L.)
Seed osmopriming invokes stress memory against post-germinative drought stress in wheat (Triticum aestivum L.)
复制标题
种子渗透启动激发小麦（Triticum aestivum L.）发芽后干旱胁迫的胁迫记忆
DOI：
10.1016/j.envexpbot.2017.10.002
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发表时间：
2018-01-01
影响因子：
5.7
通讯作者：
Dai, Tingbo
中科院分区：
文献类型：
--
作者：
Abid, Muhammad;Hakeem, Abdul;Dai, Tingbo
种子萌发引发提高了种子在正常和胁迫环境条件下的发芽性能，这一特征可能与“胁迫记忆”有关。为了研究小麦种子萌发后的干旱胁迫，我们通过遵循-0.9MPaPEG的预标准化方案在18 ℃下引发干旱敏感品种（扬麦16）的种子30小时，然后在室温下干燥。在分蘖期（Feekes 2期）和拔节期（Feekes 6期）分别对未引发和引发种子的植株进行了严重的干旱胁迫处理，研究了干旱期间叶片水分关系、光合作用、膜脂过氧化、抗氧化防御和相对生长速率的变化。此外，在成熟时记录谷物产量性状。干旱胁迫导致叶水势，相对含水量，净光合作用，量子产率，叶绿素和类胡萝卜素的含量减少，但这些性状的下降是在引发种子植物相比，unprimed种子植物。在干旱胁迫下，引发种子植物表现出较低的活性氧的形成和脂质过氧化，和较高的活性过氧化氢酶，抗坏血酸过氧化物酶，谷胱甘肽还原酶比未引发种子植物。种子萌发引发处理使小麦植株在干旱期间保持更大的相对生长速率，从而导致相对于非引发处理的更高的干物质和籽粒产量生产。由此可见，小麦种子萌发引发可产生持久的胁迫记忆，通过改变小麦对萌发后干旱胁迫的生理生化反应，稳定小麦的生长和产量。
Seed osmopriming improves gemination performance of seeds under normal and stressed environmental conditions, a feature possibly associated with 'stress memory'. To investigate whether seed osmopriming could develop tolerance to drought stress during post-germinative stages of wheat (Triticum aestivum L.), we primed the seeds of a drought-sensitive cultivar (Yangmai 16) by following a pre-standardized protocol of -0.9 MPa PEG at 18 degrees C for 30 h, and then dried at room temperature. The plants from unprimed and primed seeds were simultaneously exposed to a severe drought stress during tillering (Feekes 2 stage) and jointing (Feekes 6 stage), respectively, and we investigated the changes in leaf water relations, photosynthetic processes, lipid peroxidation, antioxidative defense, and relative growth rate during drought. Moreover, grain yield traits were recorded at maturity. Drought stress caused a reduction in leaf water potential, relative water content, net photosynthesis, quantum yield, and contents of chlorophylls and carotenoids; however, the decrease in these traits was less in primed-seed plants as compared to unprimed-seed plants. During drought stress, primed-seed plants showed lower reactive oxygen species formation and lipid peroxidation, and higher activities of catalase, ascorbate peroxidase, and glutathione reductase than unprimed-seed plants. Seed osmopriming treatment allowed wheat plants to maintain a greater relative growth rate during the drought period, resulting in higher dry matter and grain yield production relative to non-priming treatments. It was concluded that seed osmopriming resulted in long-lasting stress memory, which stabilized plant growth and productivity by altering physiological and biochemical responses to post-germinative drought stress in wheat.