Agricultural Institute, Centre for Agricultural Research, Martonvásár, 2462, Hungary.
Botany Department, Faculty of Science, Benha University, Benha, 13518, Egypt.
Plant Physiol Biochem. 2020 Apr;149:75-85. doi: 10.1016/j.plaphy.2020.02.003. Epub 2020 Feb 4.
Cold-acclimation is essential for the development of adequate frost-hardiness in cereals and therefore sudden freezes can cause considerable damage to the canopy. However, timely adding of an appropriate signal in the absence of cold acclimation may also harden wheat for the upcoming freeze. The feasibility of the promising signal molecule methylglyoxal was tested here for such applications and the signal mechanism was studied in bread wheat (Triticum aestivum L.) and durum wheat (Triticum turgidum L. ssp. durum). Spraying with 10 mM methylglyoxal did not decrease the fresh weight and photosynthetic parameters in most wheat varieties at growth temperature (21 °C). Photosynthetic parameters even improved and chlorophyll content increased in some cases. Increased transcript level of glutathione-S-transferases and omega-3 fatty acid desaturases was detected by qPCR 6 h after the last methylglyoxal spray. Aldo-keto reductase and glyoxalase enzyme activities, as well as sorbitol content of wheat plants increased 24 h after the last 10 mM methylglyoxal spray in most of the cultivars. These mechanisms may explain the increased freezing survival of methylglyoxal pretreated wheat plants from less than 10% to over 30%. Our results demonstrate that exogenous methylglyoxal treatment can be safely added to wheat plants as preparatory treatment without detrimental effects but inducing some of the stress-protective mechanisms, which contribute to frost-hardiness.
冷驯化对于谷类作物充分抗冻性的发展至关重要，因此突然的冻结会对冠层造成相当大的损害。然而，在没有冷驯化的情况下及时添加适当的信号也可以使小麦为即将到来的冻结做好准备。在这里，我们测试了有前途的信号分子甲基乙二醛在这种应用中的可行性，并研究了其信号机制在普通小麦（Triticum aestivum L.）和硬粒小麦（Triticum turgidum L. ssp. durum）中的作用。在生长温度（21°C）下，用 10mM 甲基乙二醛喷洒大多数小麦品种不会降低鲜重和光合作用参数。在某些情况下，光合作用参数甚至提高，叶绿素含量增加。用 qPCR 检测到最后一次甲基乙二醛喷雾后 6 小时，谷胱甘肽-S-转移酶和 ω-3 脂肪酸去饱和酶的转录水平增加。醛酮还原酶和甘油醛酶的活性以及小麦植物中的山梨糖醇含量在大多数品种中最后一次用 10mM 甲基乙二醛喷雾 24 小时后增加。这些机制可以解释预处理用甲基乙二醛处理的小麦植物的抗冻存活率从低于 10%提高到 30%以上。我们的研究结果表明，外源甲基乙二醛处理可以作为一种预备处理安全地添加到小麦植株中，不会产生有害影响，但会诱导一些应激保护机制，从而提高抗冻性。
