Martinez Henao Julian, Demers Louis Erik, Grosser Katharina, Schedl Andreas, van Dam Nicole M, Bede Jacqueline C
Department of Plant Science, McGill University, Ste-Anne-de-Bellevue, QC, Canada.
German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Friedrich-Schiller-University Jena, Leipzig, Germany.
Front Plant Sci. 2020 Jan 16;10:1636. doi: 10.3389/fpls.2019.01636. eCollection 2019.
The predicted future increase in tropospheric carbon dioxide (CO) levels will have major effects on C plants and their interactions with other organisms in the biosphere. In response to attack by chewing arthropod herbivores or nectrotrophic pathogens, many plants mount a rapid and intense increase in jasmonate-related phytohormones that results in a robust defense response; however, previous studies have shown that C plants grown at elevated CO may have lower induced jasmonate levels, particularly in well nitrate-fertilized plants. Given the relationship between atmospheric CO, photorespiration, cellular reductant and redox status, nitrogen assimilation and phytohormones, we compared wound-induced responses of the C plant . These plants were fertilized at two different rates (1 or 10 mM) with nitrate or ammonium and grown at ambient or elevated CO. In response to artificial wounding, an increase in cellular oxidative status leads to a strong increase in jasmonate phytohormones. At ambient CO, increased oxidative state of nitrate-fertilized plants leads to a robust 7--jasmonyl-L-isoleucine increase; however, the strong fertilizer rate-associated increase is alleviated in plants grown at elevated CO. As well, the changes in ascorbate in response to wounding and wound-induced salicylic acid levels may also contribute to the suppression of the jasmonate burst. Understanding the mechanism underlying the attenuation of the jasmonate burst at elevated CO has important implications for fertilization strategies under future predicted climatic conditions.
对流层二氧化碳（CO）水平预计在未来会上升，这将对C4植物及其与生物圈中其他生物的相互作用产生重大影响。许多植物在受到咀嚼式节肢动物食草动物或坏死营养型病原体攻击时，会迅速且强烈地增加茉莉酸相关植物激素，从而引发强大的防御反应；然而，先前的研究表明，在高浓度CO环境下生长的C4植物诱导产生的茉莉酸水平可能较低，尤其是在硝酸盐施肥充足的植物中。鉴于大气CO、光呼吸、细胞还原剂和氧化还原状态、氮同化以及植物激素之间的关系，我们比较了C4植物的创伤诱导反应。这些植物分别以两种不同的速率（1或10 mM）用硝酸盐或铵施肥，并在环境CO浓度或高浓度CO环境下生长。对人工创伤的反应中，细胞氧化状态的增加会导致茉莉酸植物激素的强烈增加。在环境CO浓度下，硝酸盐施肥植物氧化状态的增加会导致茉莉酸 - L - 异亮氨酸强劲增加；然而，在高浓度CO环境下生长的植物中，与高施肥速率相关的强劲增加会有所缓解。此外，创伤引起的抗坏血酸变化以及创伤诱导的水杨酸水平变化也可能导致茉莉酸爆发的抑制。了解高浓度CO环境下茉莉酸爆发减弱的机制，对于未来预测气候条件下的施肥策略具有重要意义。
