Akbari Mohammad, Mahna Nasser, Ramesh Katam, Bandehagh Ali, Mazzuca Silvia
Department of Horticultural Sciences, Faculty of Agriculture, University of Tabriz, Tabriz, 51666-16471, Iran.
Department of Biological Sciences, College of Science and Technology, Florida A&M University, Tallahassee, FL, 32307, USA.
Protoplasma. 2018 Sep;255(5):1349-1362. doi: 10.1007/s00709-018-1235-z. Epub 2018 Mar 12.
Pistachio, one of the important tree nuts, is cultivated in arid and semi-arid regions where salinity is the most common abiotic stress encountered by this tree. However, the mechanisms underlying salinity tolerance in this plant are not well understood. In the present study, five 1-year-old pistachio rootstocks (namely Akbari, Badami, Ghazvini, Kale-Ghouchi, and UCB-1) were treated with four saline water regimes (control, 8, 12, and 16 dS m) for 100 days. At high salinity level, all rootstocks showed decreased relative water content (RWC), total chlorophyll content (TCHC), and carotenoids in the leaf, while ascorbic acid (AsA) and total soluble proteins (TSP) were reduced in both leaf and root organs. In addition, the total phenolic compounds (TPC), proline, glycine betaine, total soluble carbohydrate (TSC), and HO content increased under salinity stress in all studied rootstocks. Three different ion exclusion strategies were observed in the studied rootstocks: (i) Na exclusion in UCB-1, because most of its Na is retained in the roots; (ii) Cl exclusion in Badami, in which most of its Cl remained in the roots; and (iii) similar concentrations of Na and Cl were observed in the leaves and roots of Ghazvini, Akbari, and Kale-Ghouchi. Transport capacity (ST value) of K over Na from the roots to the leaves was more observable in UCB-1 and Ghazvini. Overall, the root system cooperated more effectively in UCB-1 and Badami for retaining and detoxifying an excessive amount of Na and Cl. The results presented here provide important inputs to better understand the salt tolerance mechanism in a tree species for developing more salt-tolerant genotypes. Based on the results obtained here, the studied rootstocks from tolerant to susceptible are arranged as follows: UCB-1 > Badami > Ghazvini > Kale-Ghouchi > Akbari.
阿月浑子是重要的坚果树种之一，种植于干旱和半干旱地区，盐分是该树种最常见的非生物胁迫。然而，这种植物耐盐性的潜在机制尚不清楚。在本研究中，对5种1年生阿月浑子砧木（即Akbari、Badami、Ghazvini、Kale-Ghouchi和UCB-1）进行了4种盐水处理（对照、8、12和16 dS m），处理100天。在高盐度水平下，所有砧木叶片的相对含水量（RWC）、总叶绿素含量（TCHC）和类胡萝卜素均降低，而叶片和根系器官中的抗坏血酸（AsA）和总可溶性蛋白（TSP）均减少。此外，在所有研究的砧木中，盐分胁迫下总酚类化合物（TPC）、脯氨酸、甘氨酸甜菜碱、总可溶性碳水化合物（TSC）和过氧化氢（HO）含量均增加。在所研究的砧木中观察到三种不同的离子排斥策略：（i）UCB-1中的钠排斥，因为其大部分钠保留在根部；（ii）Badami中的氯排斥，其大部分氯保留在根部；（iii）在Ghazvini、Akbari和Kale-Ghouchi的叶片和根系中观察到相似浓度的钠和氯。从根部到叶片，UCB-1和Ghazvini中钾对钠的转运能力（ST值）更明显。总体而言，UCB-1和Badami的根系在保留和解毒过量的钠和氯方面合作更为有效。本文的研究结果为更好地理解树种的耐盐机制以培育更耐盐的基因型提供了重要依据。根据此处获得的结果，所研究的砧木从耐受到敏感的排序如下：UCB-1 > Badami > Ghazvini > Kale-Ghouchi > Akbari。
