Physiological, biochemical and molecular responses to low pH stress in citrus junos seedlings

ABSTRACT

Excessive soil acidity negatively affects citrus growth and development worldwide. However, less information has been presented on its tolerance to low pH stress (LPS). Here, the way in which citrus plants respond to LPS was investigated at morphological, physiological and molecular levels. Under LPS, the root length and diameter were significantly decreased. The malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents and catalase (CAT) activity were significantly enhanced. LPS increased the root indole-3-acetic acid (IAA) and gibberellins (GAs) contents, and leaf chlorophyll content. Additionally, nutrient uptake was significantly affected by LPS. RNA-seq data revealed that a total of 1319 genes responded to LPS, of which 573 and 746 genes were up- and down-regulated, respectively. These differentially expressed genes (DEGs) were mainly linked to carbon metabolism, reactive oxygen species scavenging, nutrient uptake and transport, and hormone synthesis/signalling. Taken together, our data provided an essential foundation for future elucidation of the LPS tolerance of citrus plants.

KEYWORDS:

• C. junos
• low ph
• soil acidity
• stress tolerance
• nutrient elements

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

We make Table S1 and Table S2 available in the supplementary materials.

Credit author statement

Rangjin Xie: Supervision, Conceptualisation, Writing-review & editing, Funding acquisition. Li Zheng: Methodology, Investigation. Li Zhu: review & editing. All authors commented on previous versions of the manuscript and approved the final one.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14620316.2023.2297219

Additional information

Funding

This study was supported by Ningbo Science and Technology Plan Project [202002N3019].