1
|
Sun Z, Zou Y, Xie C, Han L, Zheng X, Tian Y, Ma C, Liu X, Wang C. Brassinolide improves the tolerance of Malus hupehensis to alkaline stress. FRONTIERS IN PLANT SCIENCE 2022; 13:1032646. [PMID: 36507405 PMCID: PMC9731795 DOI: 10.3389/fpls.2022.1032646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
Malus hupehensis is one of the most widely used apple rootstocks in china but is severely damaged by alkaline soil. Alkaline stress can cause more serious harmful effects on apple plants than salt stress because it also induces high pH stress except for ion toxicity, osmotic stress, and oxidative damage. Brassinolide (BL) plays important roles in plant responses to salt stress. However, its role and function mechanism in apple plants in response to alkaline stress has never been reported. This study showed that applying exogenous 0.2 mg/L BL significantly enhanced the resistance of M. hupehensis seedlings to alkaline stress. The main functional mechanisms were also explored. First, exogenous BL could decrease the rhizosphere pH and promote Ca2+ and Mg2+ absorption by regulating malic acid and citric acid contents and increasing H+ excretion. Second, exogenous BL could alleviate ion toxicity caused by alkaline stress through enhancing Na+ efflux and inhibiting K+ expel and vacuole compartmentalization. Last, exogenous BL could balance osmotic stress by accumulating proline and reduce oxidative damage through increasing the activities of antioxidant enzymes and antioxidants contents. This study provides an important theoretical basis for further analyzing the mechanism of exogenous BL in improving alkaline tolerance of apple plants.
Collapse
Affiliation(s)
- Zhijuan Sun
- College of Life Science, Qingdao Agricultural University, Qingdao, China
| | - Yawen Zou
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Cheng Xie
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Lei Han
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Xiaodong Zheng
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Yike Tian
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Changqing Ma
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Xiaoli Liu
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| | - Caihong Wang
- College of Horticulture, Qingdao Agricultural University, Qingdao, China
- Qingdao Key Laboratory of Genetic Improvement and Breeding in Horticulture Plants, Qingdao, China
| |
Collapse
|
2
|
Sun Z, Guo D, Lv Z, Bian C, Ma C, Liu X, Tian Y, Wang C, Zheng X. Brassinolide alleviates Fe deficiency-induced stress by regulating the Fe absorption mechanism in Malus hupehensis Rehd. PLANT CELL REPORTS 2022; 41:1863-1874. [PMID: 35781542 DOI: 10.1007/s00299-022-02897-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
Exogenous brassinolide promotes Fe absorption through mechanism I strategy, thus improving the tolerance of Malus hupehensis seedlings to Fe deficiency stress. Iron (Fe) deficiency is a common nutritional disorder that results in decreased yield and poor fruit quality in apple production. As a highly active synthetic analog of brassinosteroids, brassinolide (BL) plays numerous roles in plant responses to abiotic stresses. However, its role in Fe deficiency stress in apple plants has never been reported. Herein, we found that the exogenous application of 0.2 mg L-1 BL could significantly enhance the tolerance of apple seedlings to Fe deficiency stress and result in a low etiolation rate and a high photosynthetic rate. The functional mechanisms of this effect were also explored. We found that first, exogenous BL could improve Fe absorption through the mechanism I strategy. BL induced the activity of H+-ATPase and the expression of MhAHA family genes, resulting in rhizosphere acidification. Moreover, BL could enhance the activity of Fe chelate reductase and absorb Fe through direct binding with the E-box of the MhIRT1 or MhFRO2 promoter via the transcription factors MhBZR1 and MhBZR2. Second, exogenous BL alleviated osmotic stress by increasing the contents of osmolytes (proline, solution proteins, and solution sugar) and scavenged reactive oxygen species by improving the activities of antioxidant enzymes. Lastly, exogenous BL could cooperate with other endogenous plant hormones, such as indole-3-acetic acid, isopentenyl adenosine, and gibberellic acid 4, that respond to Fe deficiency stress indirectly. This work provided a theoretical basis for the application of exogenous BL to alleviate Fe deficiency stress in apple plants.
Collapse
Affiliation(s)
- Zhijuan Sun
- College of Life Science, Qingdao Agricultural University, Qingdao, 266109, China
| | - Dianming Guo
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Zhichao Lv
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Chuanjie Bian
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Changqing Ma
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Xiaoli Liu
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Yike Tian
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Caihong Wang
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China
| | - Xiaodong Zheng
- College of Horticulture, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, 266109, China.
- Engineering Laboratory of Genetic Improvement of Horticultural Crops of Shandong Province, Qingdao, 266109, China.
| |
Collapse
|
3
|
Xudong G, Fengju Z, Teng W, Xiaowei X, Xiaohui J, Xing X. Effects of nitrogen and phosphorus addition on growth and leaf nitrogen metabolism of alfalfa in alkaline soil in Yinchuan Plain of Hetao Basin. PeerJ 2022; 10:e13261. [PMID: 35437473 PMCID: PMC9013234 DOI: 10.7717/peerj.13261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 03/22/2022] [Indexed: 01/13/2023] Open
Abstract
Alkaline soil is widely distributed in China. Its rational utilization is an effective measure to solve land shortage and improve the environment. Alfalfa is characterized by strong salt and alkali tolerance and high yield and protein content. Nitrogen (N) and phosphorus (P) are the main nutrients for plant growth, and N metabolism is one of the primary forms of plant metabolism, which plays a vital role in quality and yield formation. The exploration of the effect of N and P on N metabolism and alfalfa growth will provide a theoretical basis for scientific fertilization for alfalfa in the alkaline soil of the Yinchuan Plain of the Hetao Basin. Therefore, a 2-year experiment of N and P addition was conducted. Six treatments were set up with a randomized block design, including without N (WN), medium N (MN), high N (HN), without P (WP), medium P (MP), and high P (HP). It was found that the MN and MP treatments increased plant height, stem diameter, stem/leaf, dry/fresh, and dry matter of alfalfa. The HN and HP treatments inhibited alfalfa biomass formation. The MN and MP treatments increased key products and enzymes of leaf N metabolism of alfalfa and promoted activities of leaf nitrate reductase (NR), glutamine synthase (GS), glutamate synthase (GOGAT), glutamic-oxalacetic transaminase (GOT), and glutamic-pyruvate transaminase (GPT), and inhibited activities of leaf protease of alfalfa. The MN and MP treatments increased contents of leaf N, P, ammonium nitrogen (NH4 +-N), nitrate nitrogen (NO3 --N), total chlorophyll, and protein and reduced leaf chlorophyll a/b and amino acid, results after HN and HP treatments were opposite. The correlation among leaf P, N, NO3 --N, amino acid, and protein reached significant levels (P < 0.01). It is suggested that MN and MP treatments can improve the yield and quality of alfalfa by increasing key products and enzymes of N metabolism and can be adopted to promote alfalfa production in the alkaline soil of the Yinchuan Plain of the Hetao Basin.
Collapse
Affiliation(s)
- Gu Xudong
- School of Agriculture, Ningxia University, Yinchuan, China
| | - Zhang Fengju
- School of Ecology and Environment, Ningxia University, Yinchuan, China
| | - Wang Teng
- School of Agriculture, Ningxia University, Yinchuan, China
| | - Xie Xiaowei
- School of Agriculture, Ningxia University, Yinchuan, China
| | - Jia Xiaohui
- School of Agriculture, Ningxia University, Yinchuan, China
| | - Xu Xing
- School of Agriculture, Ningxia University, Yinchuan, China
| |
Collapse
|