Department of Horticulture, College of Aburaihan, University of Tehran, Tehran, Iran.
Department of Plant Biotechnology, Faculty of Science and Biotechnology, Shahid Beheshti University, Tehran, Iran.
Mol Biol Rep. 2022 Jan;49(1):433-441. doi: 10.1007/s11033-021-06893-x. Epub 2021 Nov 6.
Soil drought stress is a limiting factor of productivity in walnut (Juglans regia L). Ferredoxin (Fd) level decreases under adverse environmental stress. Functional replacement of decreased Fd by Fld (Flavodoxin) had been shown to have protective effect under abiotic stress condition. This study aimed to evaluate four transgenic lines (L3, L4, L13 and L17) along with non-transgenic line under three osmotic stresses levels (0, 10 and 12% PEG).
This experiment carried out based on a completely randomized design with four replications. To confirm that the Fld gene is successfully integrated into the walnut genome, PCR and dot blot analysis were carried out. The transgenic lines of walnut expressing Fld displayed increased tolerance to osmotic stress at 10 and 12% PEG condition. Lines expressing Fld exhibited increasing tolerance to drought stress and maintained health of plants under osmotic conditions. Results of real time PCR showed that expression level of Fld gene in L4 was higher than the others. Among transgenic lines, L4 was more tolerant than other lines under osmotic stress.
These findings indicate that expression of Fld gene can increase tolerance to osmotic stress in Persian walnut and is useful tool for walnut production in arid and semi-arid regions.
土壤干旱胁迫是影响核桃（Juglans regia L.）生产力的限制因素。在不利的环境胁迫下，铁氧还蛋白（Fd）水平下降。已经表明，在非生物胁迫条件下，通过 Flavodoxin（Fld）替代减少的 Fd 具有保护作用。本研究旨在评估四个转基因品系（L3、L4、L13 和 L17）以及三个渗透胁迫水平（0、10 和 12% PEG）下的非转基因品系。
本实验采用完全随机设计，设四个重复。为了证实 Fld 基因成功整合到核桃基因组中，进行了 PCR 和斑点杂交分析。表达 Fld 的核桃转基因品系在 10%和 12% PEG 条件下对渗透胁迫表现出更高的耐受性。表达 Fld 的品系在干旱胁迫下表现出更高的耐受性，并在渗透条件下保持植物的健康。实时 PCR 结果表明，L4 中的 Fld 基因表达水平高于其他品系。在转基因品系中，L4 在渗透胁迫下比其他品系更耐受。
这些发现表明，Fld 基因的表达可以提高核桃对渗透胁迫的耐受性，是干旱和半干旱地区核桃生产的有用工具。
