TY - JOUR
T1 - Halotolerant rhizobacteria isolated from a mangrove forest alleviate saline stress in Musa acuminata cv. Berangan
AU - Kaleh, Abdussabur M.
AU - Singh, Pooja
AU - Mazumdar, Purabi
AU - Chua, Kah Ooi
AU - Harikrishna, Jennifer A.
N1 - Funding Information:
This work was supported by the Innovate at University of Malaya Research Grant Programme (PPSI-2020-HICOE-06) and CEBAR Research University Grant (RU004-2020) and Post-Doctoral Fellowship Grant (RU006-2020PDCEBAR). Author PS acknowledges the financial support received from the Monash University Malaysia Post-Doctoral Fellowship Grant (STG-000058). The authors thank Dr Kien-Thai Yong, Institute of Biological Sciences & “Rimba Ilmu” (University of Malaya Botanical Gardens, University of Malaya, Malaysia), for assisting in the identification of botanical samples.
Funding Information:
This work was supported by the Innovate at University of Malaya Research Grant Programme ( PPSI-2020-HICOE-06 ) and CEBAR Research University Grant ( RU004-2020 ) and Post-Doctoral Fellowship Grant ( RU006-2020PDCEBAR ). Author PS acknowledges the financial support received from the Monash University Malaysia Post-Doctoral Fellowship Grant ( STG-000058 ). The authors thank Dr Kien-Thai Yong, Institute of Biological Sciences & “Rimba Ilmu” (University of Malaya Botanical Gardens, University of Malaya, Malaysia), for assisting in the identification of botanical samples.
Publisher Copyright:
© 2022 Elsevier GmbH
PY - 2022/12
Y1 - 2022/12
N2 - Saline soils resulting from anthropogenic activity and climate change present a challenge to future food security. Towards addressing this, we isolated and characterized halotolerant bacteria from a Malaysian mangrove forest, and explored their effect on morpho-physiological and biochemical parameters of banana plantlets under salt stress. A total of 88 rhizobacterial and 16 endophytic bacterial isolates collected from the roots and rhizosphere of Rhizophora apiculata, Avicennia alba and Sonneratia alba, were found to tolerate up to 400 mM of sea salt. Based on best performance in multiple plant growth traits, three rhizobacterial strains RB1, RB3 and RB4 and three endophytic bacterial strains EB1, EB2 and EB3 were used for further analysis. The rhizobacterial strains were identified as Bacillus sp. and endophytic bacteria as Pseudomonas sp. based on 16 S rRNA gene sequence. SEM observation confirmed colonization of each strain on banana plantlet roots. When colonized plantlets were subjected to 90 mM salt and compared to uninoculated (control) and mock inoculated plants, improved plant growth was observed with each of the strains, especially with bacterial strains EB3 and RB3. Biochemical analysis of plantlets revealed that root colonization with EB3 and RB3 enhanced levels of plant chlorophyll (> 5-fold), carotenoid (> 2.85-fold) and proline (2.6-fold and 2.3-fold), while plantlets also showed reduced MDA content (0.45-fold and 0.51-fold), significantly reduced generation of ROS (0.23-fold and 0.47-fold) and lower levels of electrolyte leakage (0.77 and 0.51-fold). Antioxidant enzymes also showed enhanced activity with EB3 and RB3. Our results indicate that these halotolerant Bacillus and Pseudomonas strains from the mangrove have multifunctional plant growth promoting activity and can reduce salt stress in bananas. This data provides a reference for exploring halotolerant microbes from hypersaline environments to overcome salt stress in plants.
AB - Saline soils resulting from anthropogenic activity and climate change present a challenge to future food security. Towards addressing this, we isolated and characterized halotolerant bacteria from a Malaysian mangrove forest, and explored their effect on morpho-physiological and biochemical parameters of banana plantlets under salt stress. A total of 88 rhizobacterial and 16 endophytic bacterial isolates collected from the roots and rhizosphere of Rhizophora apiculata, Avicennia alba and Sonneratia alba, were found to tolerate up to 400 mM of sea salt. Based on best performance in multiple plant growth traits, three rhizobacterial strains RB1, RB3 and RB4 and three endophytic bacterial strains EB1, EB2 and EB3 were used for further analysis. The rhizobacterial strains were identified as Bacillus sp. and endophytic bacteria as Pseudomonas sp. based on 16 S rRNA gene sequence. SEM observation confirmed colonization of each strain on banana plantlet roots. When colonized plantlets were subjected to 90 mM salt and compared to uninoculated (control) and mock inoculated plants, improved plant growth was observed with each of the strains, especially with bacterial strains EB3 and RB3. Biochemical analysis of plantlets revealed that root colonization with EB3 and RB3 enhanced levels of plant chlorophyll (> 5-fold), carotenoid (> 2.85-fold) and proline (2.6-fold and 2.3-fold), while plantlets also showed reduced MDA content (0.45-fold and 0.51-fold), significantly reduced generation of ROS (0.23-fold and 0.47-fold) and lower levels of electrolyte leakage (0.77 and 0.51-fold). Antioxidant enzymes also showed enhanced activity with EB3 and RB3. Our results indicate that these halotolerant Bacillus and Pseudomonas strains from the mangrove have multifunctional plant growth promoting activity and can reduce salt stress in bananas. This data provides a reference for exploring halotolerant microbes from hypersaline environments to overcome salt stress in plants.
KW - Bacillus
KW - Banana
KW - Mangrove
KW - Plant growth promoting bacteria (PGPB)
KW - Pseudomonas
KW - Salinity
UR - https://www.scopus.com/pages/publications/85137175666
U2 - 10.1016/j.micres.2022.127176
DO - 10.1016/j.micres.2022.127176
M3 - Article
C2 - 36088726
AN - SCOPUS:85137175666
SN - 0944-5013
VL - 265
JO - Microbiological Research
JF - Microbiological Research
M1 - 127176
ER -
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