Czerniewicz Paweł, Sytykiewicz Hubert, Durak Roma, Borowiak-Sobkowiak Beata, Chrzanowski Grzegorz
Department of Biochemistry and Molecular Biology, Siedlce University of Natural Sciences and Humanities, Prusa 12, 08-110 Siedlce, Poland.
Department of Invertebrate Zoology, University of Rzeszów, Zelwerowicza 4, 35-601 Rzeszów, Poland.
Plant Physiol Biochem. 2017 Sep;118:529-540. doi: 10.1016/j.plaphy.2017.07.024. Epub 2017 Jul 29.
One of the earliest responses of plants to insects' attack is generation of reactive oxygen species. However, the elevated level of ROS can elicit oxidative burst within plant tissues, and plants employ antioxidant systems against these radicals. Due to their chemical structures, polyphenols are able to diminish the level of ROS. Thus, we investigated the role of phenolic compounds in oxidative stress within winter triticale caused by Sitobion avenae and Oulema melanopus. It was found, that infestation by insects induced a high increase in the content of hydrogen peroxide and superoxide anion radical within resistant Lamberto cv. 24 hpi, whereas in sensitive Marko cv., an increase in HO content was found within two days of aphid feeding. Moreover, resistant plants showed earlier and much greater induction of l-phenylalanine and l-tyrosine ammonia lyases and chalcone synthase activities, as well as accumulation of phenolic compounds in response to insect feeding than susceptible Marko. On the other hand, strong positive influence of hydrogen peroxide and superoxide radical contents on chalcone synthase activity and furthermore flavonoid biosynthesis was detected in the susceptible cultivar. Negative relationships between level of o-coumaric acid or flavonoid compounds and content of hydrogen peroxide or superoxide radical suggest their antioxidant capacity. Luteolin and o-coumaric acid may attend in scavenging of hydrogen peroxide, whereas quercetin, apigenin and (+)-catechin probably participate in reduction of superoxide anion radical content.
植物对昆虫攻击的最早反应之一是活性氧的产生。然而，活性氧水平的升高会引发植物组织内的氧化爆发，植物会利用抗氧化系统来对抗这些自由基。由于其化学结构，多酚能够降低活性氧水平。因此，我们研究了酚类化合物在由麦长管蚜和黑麦鞘叶甲引起的冬小黑麦氧化应激中的作用。研究发现，在抗性品种Lamberto cv.中，昆虫侵染在接种后24小时诱导过氧化氢和超氧阴离子自由基含量大幅增加，而在敏感品种Marko cv.中，在蚜虫取食两天内发现过氧化氢含量增加。此外，与易感的Marko相比，抗性植物对昆虫取食的反应表现出更早且更强的苯丙氨酸解氨酶、酪氨酸解氨酶和查尔酮合酶活性诱导以及酚类化合物积累。另一方面，在易感品种中检测到过氧化氢和超氧自由基含量对查尔酮合酶活性进而对类黄酮生物合成有强烈的正向影响。邻香豆酸或类黄酮化合物水平与过氧化氢或超氧自由基含量之间的负相关关系表明它们具有抗氧化能力。木犀草素和邻香豆酸可能参与过氧化氢的清除，而槲皮素、芹菜素和（+）-儿茶素可能参与超氧阴离子自由基含量的降低。
