scholarly journals The Growth Promotion of Two Salt-Tolerant Plant Groups with PGPR Inoculation: A Meta-Analysis

2019 ◽  
Vol 11 (2) ◽  
pp. 378 ◽  
Author(s):  
Jing Pan ◽  
Fei Peng ◽  
Xian Xue ◽  
Quangang You ◽  
Wenjuan Zhang ◽  
...  

Understanding the primary mechanisms for plant promotion under salt stress with plant growth promoting rhizobacteria (PGPR) inoculation of different salt-tolerant plant groups would be conducive to using PGPR efficiently. We conducted a meta-analysis to evaluate plant growth promotion and uncover its underlying mechanisms in salt-sensitive plants (SSP) and salt-tolerant plants (STP) with PGPR inoculation under salt stress. PGPR inoculation decreased proline, sodium ion (Na+) and malondialdehyde but increased plant biomass, nutrient acquisition (nitrogen, phosphorus, potassium ion (K+), calcium ion (Ca2+), and magnesium ion (Mg2+)), ion homeostasis (K+/Na+ ratio, Ca2+/Na+ ratio, and Mg2+/Na+ ratio), osmolytes accumulation (soluble sugar and soluble protein), antioxidants (superoxide dismutase), and photosynthesis (chlorophyll, carotenoid, and photosynthetic rate) in both SSP and STP. The effect size of total biomass positively correlated with the effect sizes of nutrient acquisition and the homeostasis of K+/Na+, and negatively correlated with the effect size of malondialdehyde in both SSP and STP. The effect size of total biomass also positively correlated with the effect sizes of carotenoid and the homeostasis in Ca2+/Na+ and Mg2+/Na+ and negatively correlated with the effect size of Na+ in SSP, but it only negatively correlated with the effect size of Ca2+ in STP. Our results suggest that the plant growth improvement depends on the nutrient acquisition enhancement in both SSP and STP, while ion homeostasis plays an important role and carotenoid may promote plant growth through protecting photosynthesis, reducing oxidative damage and promoting nutrient acquisition only in SSP after PGPR inoculation under salt stress.

Author(s):  
Md. Shoaib Arifin ◽  
Md. Shafiul Islam Rion ◽  
Atiqur Rahman ◽  
H. M. Zakir ◽  
Quazi Forhad Quadir

Plant growth-promoting rhizobacteria can effectively reduce the severity of different abiotic stresses like water stress, temperature stress, salt stress, etc. on plant growth and development. The study aimed at isolating salt-tolerant rhizobacteria followed by their morphological, biochemical and plant growth promotion traits evaluation. Sixteen root samples of nine different plant species were collected from two locations of Patuakhali, a coastal southern district of Bangladesh. Thirty rhizobacteria were isolated, fifteen from each location, to assess their halotolerance and plant growth promoting potential. The isolated rhizobacteria were subjected to morphological (viz. shape, colour and elevation), biochemical (viz. Gram reaction, catalase test and HCN production) and growth-promoting traits [viz. phosphate solubilizing ability, salt tolerance, indole-3-acetic acid (IAA) production, and N2-fixation] characterization. Twenty-eight isolates were Gram positive, 27 were catalase positive, and nine showed varying degrees of phosphate solubilization on National Botanical Research Institute of Phosphate (NBRIP) medium. Isolate PWB5 showed the highest phosphate solubilizing index (PSI = 3.83±0.098) on the 6th day. To screen salt-tolerant rhizobacteria, the isolates were cultured in NBA media containing different (0%, 2.5%, 5%, 7.5%, 10%, 12%, 15%) NaCl concentrations. Isolate PWB12 and PWB13 grew at 15% NaCl concentration. Eleven isolates exhibited IAA producing ability on Winogradsky medium amended with L-tryptophan among which four (PMB13, PMB14, PMB15 and PWB6) were strong IAA producers. Twenty-seven isolates were potential N2-fixer and among them, 20 were highly efficient, but none of the isolates was HCN producer. The rhizobacteria isolated in the current research work showed some potential plant growth-promoting traits which seem applicable for crop production, especially, under salt stress condition.


2016 ◽  
Vol 5 (12) ◽  
pp. 5118 ◽  
Author(s):  
Anukool Vaishnav* ◽  
Sarita Kumari ◽  
Shekhar Jain ◽  
Devendra Kumar Choudhary ◽  
Kanti Prakash Sharma

Salinity is a major limiting factor for soybean crop productivity. To enhance the tolerance of soybean against salt stress, it is essential to understand the diversity of microbiota harboured by soybean rhizosphere. Earlier studies have demonstrated that local adaptation of plants to habitat imposed stresses is driven by their closely associated microbes. The present study aimed to isolation and characterization of salt tolerant rhizobacteria with respect to their functional plant growth promotion ability. A total of 43 bacterial isolates were recovered from soybean rhizospheric soil grown in Bundi district, Rajasthan, India. Out of them, one bacterial isolate strain AU was found to tolerate 10% NaCl stress and significantly enhanced soybean seedlings growth under 100mM NaCl condition. Molecular phylogenetic analysis placed this isolate closely to Pseudomonas simiae OLiT with 99.93% similarity. Molecular characterization of functional genes revealed that AU bacterium possessed genes like IaaM (IAA production), g6pd (Pi-solubilization) and sid (siderophore production). Here, we show that soybean rhizosphere possessed a salt tolerant plant growth promoting bacterium strain AU, which may have impacts on alleviation and tolerance of salt stress in legume plants.


2021 ◽  
Vol 138 ◽  
pp. 94-104
Author(s):  
Guendouz Dif ◽  
Hadj Ahmed Belaouni ◽  
Yacine Goudjal ◽  
Amine Yekkour ◽  
Nadjette Djemouai ◽  
...  

2015 ◽  
Vol 3 (3) ◽  
pp. 552-560 ◽  
Author(s):  
Mohamed A.M. El-Awady ◽  
Mohamed M. Hassan ◽  
Yassin M. Al-Sodany

This study was designed to isolate and characterize endophytic and rhizospheric bacteria associated with the halophyte plant Sesuvium verrucosum, grown under extreme salinity soil in Jeddah, Saudi Arabia. The plant growth promotion activities of isolated bacterial were evaluated in vitro. A total of 19 salt tolerant endophytic and rhizospheric bacterial isolates were obtained and grouped into six according to genetic similarity based on RAPD data. These six isolates were identified by amplification and partial sequences of 16S rDNA as Enterobacter cancerogenus,Vibrio cholerae, Bacillus subtilis, Escherichia coli and two Enterobacter sp. Isolates were then grown until exponential growth phase to evaluate the atmospheric nitrogen fixation, phosphate solubilization, and production of phytohormones such as indole-3-acetic acid, as well as 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. While, All of the six strains were negative for ACC deaminaseactivity, two isolates showed Nitrogen fixation activity, three isolates produce the plant hormone (Indole acetic acid) and two isolates have the activity of solubiliztion of organic phosphate. Among the six isolates, the isolate (R3) from the soil around the roots is able to perform the three previous growth promoting possibilities together and it is ideal for use in promoting the growth of plants under the high salinity conditions. This isolate is candidate to prepare a friendly biofertelizer that can be used for the improvement of the crops performance under salinity conditions.Int J Appl Sci Biotechnol, Vol 3(3): 552-560


2020 ◽  
Author(s):  
Razieh Kiani ◽  
Ahmad Arzani ◽  
S. A. M. Mirmohammady Meibody ◽  
Mehdi Rahimmalek ◽  
Khadijeh Razavi

AbstractAegilops cylindrica Host is one of the most salt-tolerant species in the Triticeae tribe. Amphidiploid plants derived from hybridization of ‘Roshan’ × Aegilops cylindrica and ‘Chinese Spring’ × Ae. cylindrica genotypes contrasting in salt tolerance were assessed for their morpho-physiological responses and the expression patterns of two genes related to ion homeostasis under 250 mM NaCl. Results showed that salt stress caused significant declines in both their morphological and phenological traits. Moreover, salt stress reduced not only their chlorophyll content but also their root and shoot K contents and K/Na ratios, while it led to significant enhancements in the remaining traits. Similar to Ae. cylindrica, the amphidiploids subjected to salt stress exhibited significantly higher H2O2 levels, root and shoot K contents, and root and shoot K/Na ratios accompanied by lower root and shoot Na contents and MDA concentrations when compared with the same traits in the wheat parents. Quantitative Real-Time PCR showed significant differential expression patterns of the NHX1 and HKT1;5 genes between the amphidiploids and their parents. The transcript level of HKT1;5 was found to be higher in the roots than in the shoots of both the amphidiploids and Ae. cylindrica while NHX1 exhibited a higher expression in the shoot tissues. The consistency of these data provides compelling support for the hypothesis that active exclusion of Na from the roots and elevated vacuolar sequestration of Na in the leaves might explain the declining Na levels in the shoots and roots of both the amphidiploids and Ae. cylindrica relative to those measured in wheat parents. It is concluded that the hybridized amphiploids are potentially valuable resources for salt improvement in bread wheat through the backcrossing approach.


2020 ◽  
Vol 66 (2) ◽  
pp. 144-160 ◽  
Author(s):  
Shahnaz Sultana ◽  
Sumonta C. Paul ◽  
Samia Parveen ◽  
Saiful Alam ◽  
Naziza Rahman ◽  
...  

Growth and productivity of rice are negatively affected by soil salinity. However, some salt-tolerant rhizosphere-inhabiting bacteria can improve salt resistance of plants, thereby augmenting plant growth and production. Here, we isolated a total of 53 plant-growth-promoting rhizobacteria (PGPR) from saline and non-saline areas in Bangladesh where electrical conductivity was measured as >7.45 and <1.80 dS/m, respectively. Bacteria isolated from saline areas were able to grow in a salt concentration of up to 2.60 mol/L, contrary to the isolates collected from non-saline areas that did not survive beyond 854 mmol/L. Among the salt-tolerant isolates, Bacillus aryabhattai, Achromobacter denitrificans, and Ochrobactrum intermedium, identified by comparing respective sequences of 16S rRNA using the NCBI GenBank, exhibited a higher amount of atmospheric nitrogen fixation, phosphate solubilization, and indoleacetic acid production at 200 mmol/L salt stress. Salt-tolerant isolates exhibited greater resistance to heavy metals and antibiotics, which could be due to the production of an exopolysaccharide layer outside the cell surface. Oryza sativa L. fertilized with B. aryabhattai MS3 and grown under 200 mmol/L salt stress was found to be favoured by enhanced expression of a set of at least four salt-responsive plant genes: BZ8, SOS1, GIG, and NHX1. Fertilization of rice with osmoprotectant-producing PGPR, therefore, could be a climate-change-preparedness strategy for coastal agriculture.


Sign in / Sign up

Export Citation Format

Share Document