The Multifarious PGPR Serratia marcescens CDP-13 Augments Induced Systemic Resistance and Enhanced Salinity Tolerance of Wheat (Triticum aestivum L.)

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.

Potential of efficient and resistant plant growth‐promoting rhizobacteria in lead uptake and plant defence stimulation in Lathyrus sativus under lead stress

“…Furthermore, inoculation with PGPR significantly increased soluble sugar content in L. sativus, as compared to uninoculated plants, with a maximum in leaves and roots of plants inoculated with I5. Such improvement in total soluble sugars after PGPR inoculation has been reported in other studies (Sandhya et al 2010;Singh & Jha 2016). It has been suggested that soluble sugars serve as signals that not only sense and control photosynthetic activity but also sense and control the ROS balance (Cou ee et al 2006).…”

“…Such improvement in total soluble sugars after PGPR inoculation has been reported in other studies (Sandhya et al . ; Singh & Jha ). It has been suggested that soluble sugars serve as signals that not only sense and control photosynthetic activity but also sense and control the ROS balance (Couée et al .…”

Modulation of Salt Stress Induced Responses in Pea (Pisum sativum L.) Through Salicylic Acid and Trichoderma Application

“…Reactive oxygen species such as superoxide radical and H 2 O 2 content were significantly increased with increase in NaCl concentration in the present study (Singh and Jha, 2016;Hashem et al, 2016). These were found to decrease with application of SA and Trichoderma under salt stress situation by activation of different antioxidative enzymes i.e., SOD and APX under salinity stress.…”

Effects of exogenously applied plant growth regulators in combination with PGPR on the physiology and root growth of chickpea (Cicer arietinum) and their role in drought tolerance

“…Sandhya et al (2010) demonstrated the antagonistic effects of drought stress on plant growth under uninoculated condition may be credited to reduction in the content of starch and sugar. Serratia marcescens CDP-13 enhanced salinity tolerance of chickpea by modulating the concentrations of different osmo-protectants including sugars (Singh and Jha 2016). SA treatments had profound effects on sugar content.…”