Effects of Salt Stress on the Antioxidant Activity and Malondialdehyde, Solution Protein, Proline, and Chlorophyll Contents of Three <i>Malus</i> Species

Understanding the different physiological responses of <i>Malus</i> species under salt stress in the seedling stages will be useful in breeding salt-tolerant dwarfing apple rootstocks. Seedlings of <i>Malus Zumi</i> (Mats.) Rehd. (<i>M. zumi</i>), <i>Malus s...

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Bibliographic Details
Main Authors: Dajiang Wang, Yuan Gao, Simiao Sun, Xiang Lu, Qingshan Li, Lianwen Li, Kun Wang, Jihong Liu
Format: Article
Language:English
Published: MDPI AG 2022-11-01
Series:Life
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Online Access:https://www.mdpi.com/2075-1729/12/11/1929
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Summary:Understanding the different physiological responses of <i>Malus</i> species under salt stress in the seedling stages will be useful in breeding salt-tolerant dwarfing apple rootstocks. Seedlings of <i>Malus Zumi</i> (Mats.) Rehd. (<i>M. zumi</i>), <i>Malus sieversii</i> (Led.) Roem. (<i>M. sieversii</i>), and <i>Malus baccata</i> (L.) Borkh. (<i>M. baccata</i>) were treated with solution of 0, 0.20%, 0.40%, and 0.60% salinity. Physiological parameters of their leaves and roots were measured at 0 d, 4 d, 8 d and 12 d after salinity treatments. Superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), malondialdehyde (MDA), solution protein (SP), and proline (PRO) initially increased and then decreased. The activities and contents of these parameters were higher in the 0.40% and 0.60% NaCl treatments than in the 0.20% treatment and in the 0% control. <i>M. zumi</i> was the most resistant to salt stress, showing the lowest content of MDA in the leaves and roots, which increased slightly under salt stress. <i>M. baccata</i> had the highest increase in both the content and proportion of MDA. High enzyme activity was shown to play an important role in the salt resistance of <i>M. zumi</i>. Moreover, it can be speculated that there are other substances that also play a major role. We found that osmotic regulation played a key role in response to salt stress for <i>M. baccata</i> even though it was sensitive to salt stress. For <i>M. sieversii</i>, both the osmotic regulation and enzymatic antioxidants were observed to play a major role in mitigating salt stress.
ISSN:2075-1729