Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars
In the present study, 217 rhizobacterial isolates were obtained from six different tea estates of Assam, India and subjected to preliminary in vitro plant growth promotion (PGP) screening for indole acetic acid (IAA) production, phosphate solubilization, siderophore production and ammonia production...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2015-11-01
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| Series: | Frontiers in Microbiology |
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| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fmicb.2015.01252/full |
| _version_ | 1818563726418116608 |
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| author | Jintu eDutta Pratap Jyoti Handique Debajit eThakur |
| author_facet | Jintu eDutta Pratap Jyoti Handique Debajit eThakur |
| author_sort | Jintu eDutta |
| collection | DOAJ |
| description | In the present study, 217 rhizobacterial isolates were obtained from six different tea estates of Assam, India and subjected to preliminary in vitro plant growth promotion (PGP) screening for indole acetic acid (IAA) production, phosphate solubilization, siderophore production and ammonia production. 50 isolates showed all the PGP traits and 5 isolates did not exhibit any PGP traits. These 50 potential isolates were further analyzed for quantitative estimation of the PGP traits along with the aminocyclopropane-1-carboxylate (ACC) deaminase, protease and cellulose production. After several rounds of screening, four rhizobacteria were selected based on their maximum ability to produce in vitro PGP traits and their partial 16S rRNA gene sequence analysis revealed that they belong to Enterobacter lignolyticus strain TG1, Burkholderia sp. stain TT6, Bacillus pseudomycoides strain SN29 and Psedumonas aeruginosa strain KH45. To evaluate the efficacy of these four rhizobacteria as plant growth promoters, three different commercially important tea clones TV1, TV19 and TV20 plants were inoculated with these rhizobacteria in greenhouse condition and compared to the uninoculated control plants. Though, all the rhizobacterial treatments showed an increase in plant growth compared to control but the multivariate PCA analysis confirmed more growth promotion by TG1 and SN29 strains than the other treatments in all three clones. To validate this result, the fold change analysis was performed and it revealed that the tea clone TV19 plants inoculated with the E. lignolyticus strain TG1 showed maximum root biomass production with an increase in 4.3 fold, shoot biomass with increase in 3.1 fold, root length by 2.2 fold and shoot length by 1.6 fold. Moreover, two way ANOVA analysis also revealed that rhizobacterial treatment in different tea clones showed the significant increase (p<0.05) in growth promotion compared to the control. Thus, this study indicates that the potential of these indigenous PGPR isolates to use as microbial inoculation or biofertilizer for growth promotion of tea crops. |
| first_indexed | 2024-12-14T01:20:09Z |
| format | Article |
| id | doaj.art-98b52b4ab43344ed96b3b1d8fc60f04d |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-14T01:20:09Z |
| publishDate | 2015-11-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-98b52b4ab43344ed96b3b1d8fc60f04d2022-12-21T23:22:26ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2015-11-01610.3389/fmicb.2015.01252168212Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivarsJintu eDutta0Pratap Jyoti Handique1Debajit eThakur2Institute of Advanced Study in Science and TechnologyGauhati UniversityInstitute of Advanced Study in Science and TechnologyIn the present study, 217 rhizobacterial isolates were obtained from six different tea estates of Assam, India and subjected to preliminary in vitro plant growth promotion (PGP) screening for indole acetic acid (IAA) production, phosphate solubilization, siderophore production and ammonia production. 50 isolates showed all the PGP traits and 5 isolates did not exhibit any PGP traits. These 50 potential isolates were further analyzed for quantitative estimation of the PGP traits along with the aminocyclopropane-1-carboxylate (ACC) deaminase, protease and cellulose production. After several rounds of screening, four rhizobacteria were selected based on their maximum ability to produce in vitro PGP traits and their partial 16S rRNA gene sequence analysis revealed that they belong to Enterobacter lignolyticus strain TG1, Burkholderia sp. stain TT6, Bacillus pseudomycoides strain SN29 and Psedumonas aeruginosa strain KH45. To evaluate the efficacy of these four rhizobacteria as plant growth promoters, three different commercially important tea clones TV1, TV19 and TV20 plants were inoculated with these rhizobacteria in greenhouse condition and compared to the uninoculated control plants. Though, all the rhizobacterial treatments showed an increase in plant growth compared to control but the multivariate PCA analysis confirmed more growth promotion by TG1 and SN29 strains than the other treatments in all three clones. To validate this result, the fold change analysis was performed and it revealed that the tea clone TV19 plants inoculated with the E. lignolyticus strain TG1 showed maximum root biomass production with an increase in 4.3 fold, shoot biomass with increase in 3.1 fold, root length by 2.2 fold and shoot length by 1.6 fold. Moreover, two way ANOVA analysis also revealed that rhizobacterial treatment in different tea clones showed the significant increase (p<0.05) in growth promotion compared to the control. Thus, this study indicates that the potential of these indigenous PGPR isolates to use as microbial inoculation or biofertilizer for growth promotion of tea crops.http://journal.frontiersin.org/Journal/10.3389/fmicb.2015.01252/full16S rRNAPGP traitsPlant growth promoting rhizobacteriaTea growth promotiontea rhizosphere |
| spellingShingle | Jintu eDutta Pratap Jyoti Handique Debajit eThakur Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars Frontiers in Microbiology 16S rRNA PGP traits Plant growth promoting rhizobacteria Tea growth promotion tea rhizosphere |
| title | Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars |
| title_full | Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars |
| title_fullStr | Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars |
| title_full_unstemmed | Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars |
| title_short | Assessment of culturable tea rhizobacteria isolated from tea estates of Assam, India for growth promotion in commercial tea cultivars |
| title_sort | assessment of culturable tea rhizobacteria isolated from tea estates of assam india for growth promotion in commercial tea cultivars |
| topic | 16S rRNA PGP traits Plant growth promoting rhizobacteria Tea growth promotion tea rhizosphere |
| url | http://journal.frontiersin.org/Journal/10.3389/fmicb.2015.01252/full |
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