Abstract
The present study demonstrates the plant growth promoting (PGP) potential of a bacterial isolate CDP-13 isolated from ‘Capparis decidua’ plant, and its ability to protect plants from the deleterious effect of biotic and abiotic stressors. Based on 16S rRNA gene sequence analysis, the isolate was identified as Serratia marcescens. Among the PGP traits, the isolate was found to be positive for ACC deaminase activity, phosphate solubilization, production of siderophore, indole acetic acid production, nitrogen fixation, and ammonia production. CDP-13 showed growth at an increased salt (NaCl) concentration of up to 6%, indicating its potential to survive and associate with plants growing in saline soil. The inoculation of S. marcescens enhanced the growth of wheat plant under salinity stress (150–200 mM). It significantly reduced inhibition of plant growth (15 to 85%) caused by salt stressors. Application of CDP-13 also modulated concentration (20 to 75%) of different osmoprotectants (proline, malondialdehyde, total soluble sugar, total protein content, and indole acetic acid) in plants suggesting its role in enabling plants to tolerate salt stressors. In addition, bacterial inoculation also reduced the disease severity caused by fungal infection, which illustrated its ability to confer induced systemic resistance (ISR) in host plants. Treatment of wheat plants with the test organism caused alteration in anti-oxidative enzymes activities (Superoxide dismutase, Catalase, and Peroxidase) under various salinity levels, and therefore minimizes the salinity-induced oxidative damages to the plants. Colonization efficiency of strain CDP-13 was confirmed by CFU count, epi-fluorescence microscopy, and ERIC-PCR-based DNA fingerprinting approach. Hence, the study indicates that bacterium CDP-13 enhances plant growth, and has potential for the amelioration of salinity stress in wheat plants. Likewise, the results also provide insights into biotechnological approaches to using PGPR as an alternative to chemicals and pesticides.
Highlights
Salinity is the most common abiotic stressor, which severely affects the plant growth and productivity
To evaluate the possible roles of the antioxidant defence system and osmolytes for salinity tolerance, we investigated the activities of several antioxidant enzymes (SOD, POX, and CAT) as well as accumulation of major solutes, including proline (Pro), total soluble sugar (TSS) and total soluble protein (TSP) following inoculation of selected bacterium
Luxuriantly growing bacterial isolate CDP-13 was selected for further characterization and experimental studies
Summary
Salinity is the most common abiotic stressor, which severely affects the plant growth and productivity. More than 6% of the total land area of the world is salt affected especially in arid and semiarid zones [1]. Salinity affects 19.5% of irrigated land and 2.1% of dry land agriculture worldwide. In India, salinity alone affects 7 million hectares of land [2]. Accumulation of salt-rich water decreases the osmotic potential, thereby decreasing the availability of water to the plants. In addition to deleterious osmotic effects, salt stress causes the toxic ionic effect to the plants. Plants subjected to salinity stress generate the reactive oxygen species (ROS) causing oxidative damages that adversely affect the plant development [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
