College of Life Sciences, Zaozhuang University, Zaozhuang, China; State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, Shandong, China; Shandong Shofine Seed Technology Co., Ltd, China.
State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, Shandong, China; College of Agriculture and Bioengineering, Heze University, He'ze, Shandong, China; Shandong Shofine Seed Technology Co., Ltd, China.
J Plant Physiol. 2021 May;260:153404. doi: 10.1016/j.jplph.2021.153404. Epub 2021 Mar 9.
Isochorismate synthase (ICS) is a key enzyme for the synthesis of salicylic acid (SA) in plants. SA mediates plant responses to both biotic and abiotic stresses. In previous studies, we found that overexpression of ICS (ICS) or suppression of ICS (ICS) affected the host response to Fusarium graminearum in barley. However, whether the barley ICS gene plays a role in adapting to abiotic stresses remains to be determined. In the present study, expression of the ICS gene was upregulated when treated with 20 % PEG6000, and ICS lines were more drought tolerant than wild type (WT) and ICS. In addition, the abscisic acid (ABA) levels in the ICS lines were higher than those in the WT and ICS lines under drought stress. High ABA levels significantly reduced Gs and E, which may impact water retention under drought stress. Under drought conditions, the activity of antioxidant enzymes was significantly higher in the ICS lines, correlating with a lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Enhanced antioxidant competence also contributed to drought tolerance in ICS lines. These findings help elucidate the abiotic stress resistance of the ICS pathway in barley.
分支酸合酶（ICS）是植物中合成水杨酸（SA）的关键酶。SA 介导植物对生物和非生物胁迫的反应。在之前的研究中，我们发现 ICS 的过表达（ICS）或抑制（ICS）会影响大麦对禾谷镰刀菌的宿主反应。然而，大麦 ICS 基因是否在适应非生物胁迫中发挥作用仍有待确定。在本研究中，用 20%PEG6000 处理时，ICS 基因的表达上调，ICS 系比野生型（WT）和 ICS 系更耐旱。此外，在干旱胁迫下，ICS 系中的脱落酸（ABA）水平高于 WT 和 ICS 系。高 ABA 水平显著降低了 Gs 和 E，这可能会影响干旱胁迫下的水分保持。在干旱条件下，ICS 系中的抗氧化酶活性显著升高，与活性氧（ROS）和丙二醛（MDA）水平较低相关。增强的抗氧化能力也有助于 ICS 系的耐旱性。这些发现有助于阐明大麦 ICS 途径的非生物胁迫抗性。
