Low pH alleviated salinity stress of ginger seedlings by enhancing photosynthesis, fluorescence, and mineral element contents

Fengman Yin; Shanying Zhang; Bili Cao; Kun Xu

doi:10.7717/peerj.10832

Low pH alleviated salinity stress of ginger seedlings by enhancing photosynthesis, fluorescence, and mineral element contents

PeerJ. 2021 Feb 11:9:e10832. doi: 10.7717/peerj.10832. eCollection 2021.

Authors

Fengman Yin^#^{1

2

3

4}, Shanying Zhang^#⁵, Bili Cao^{1

2

3

4}, Kun Xu^{1

2

3

4}

Affiliations

¹ College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, Shandong, China.
² Collaborative Innovation Center of Fruit & Vegetable Quality and Efficient Production in Shandong, Tai'an, China.
³ Key Laboratory of Biology and Genetic Improvement of Horticultural Crops in Huanghuai Region, Ministry of Agriculture and Rural Affairs, P.R. China, Tai'an, China.
⁴ State Key Laboratory of Crop Biology, Tai'an, China.
⁵ College of Food Science, Hainan University, Haikou, Hainan, China.

^# Contributed equally.

Abstract

We investigated the effects of low pH on the photosynthesis, chlorophyll fluorescence, and mineral contents of the leaves of ginger plants under salt stress. This experiment involved four treatments: T1 (pH 6, 0 salinity), T2 (pH 4, 0 salinity), T3 (pH 6, 100 mmol L^-1 salinity) and T4 (pH 4, 100 mmol L^-1 salinity). This study showed that photosynthesis (Pn, Gs, WUE and Tr) and chlorophyll fluorescence (qP, Φ PSII, and Fv/Fm) significantly decreased under salt stress; however, all the parameters of the ginger plants under the low-pH treatment and salt stress recovered. Moreover, low pH reduced the content of Na and enhanced the contents of K, Mg, Fe and Zn in the leaves of ginger plants under salt stress. Taken together, these results suggest that low pH improves photosynthesis efficiency and nutrient acquisition and reduces the absorption of Na, which could enhance the salt tolerance of ginger.

Keywords: Photosynthesis; Chlorophyll fluorescence; Ginger; Low pH; Mineral contents; Salt stress.

Grants and funding

This work was supported by the TaiShan Industrial Experts Program, China (Grant No. tscy20190105), the Project of agricultural excellent germplasm in Shandong province (Grant No. 2020LZGC006), the Industrial technology system of national specialty vegetables (Grant No. CARS-24-A-09), and the National Natural Science Foundation of China (Grant No. 31972399). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.