@article {47063, title = {Rhizobacterial consortium mediated aroma and yield enhancement in basmati and non-basmati rice ( Oryza sativa L.)}, journal = {Journal of Biotechnology}, volume = {328}, year = {2021}, month = {FEB}, pages = {47-58}, type = {Article}, abstract = {

Basmati and non-basmati rice varieties are commercially important. Aromatic rice varieties are low yielding and recently depletion in aroma is observed due to the shift towards modern agriculture. Therefore, it is necessary to restore the aroma and increase the yield through sustainable agriculture. The use of microbial bioinoculants is one of the promising ways to achieve these targets. With these objectives, rhizospheric bacterial strains Enterobacter hormaechei (AM122) and Lysinibacillus xylanilyticus (DB25) having the property of synthesizing 2acetyl-1-pyrroline (2AP) were isolated from the rhizosphere of two aromatic rice varieties, Ambemohar-157 and Dehradun Basmati respectively and their effect on plant growth, aroma and yield enhancement under mono-inoculation and consortium conditions was analyzed. The bacterial inoculum in consortium resulted in significant improvement in vegetative growth, yield and 2AP content over mono inoculation and control. The study highlights the potential of E. hormaechei and L. xylanilyticus in plant growth, yield and aroma enhancement in basmati and non-basmati rice varieties. These strains can be taken up further for developing a commercial bioformulation.

}, keywords = {2-Acetyl-1-pyrroline, Basmati rice, Non-basmati rice, plant growth promotion, Rhizosphere, yield}, issn = {0168-1656}, doi = {10.1016/j.jbiotec.2021.01.012}, author = {Dhondge, Harshal V. and Pable, Anupama A. and Barvkar, Vitthal T. and Dastager, Syed G. and Nadaf, Altafhusain B.} } @article {48177, title = {Exploring the core microbiota in scented rice (Oryza sativa L.) rhizosphere through metagenomics approach}, journal = {Microbiological Research}, volume = {263}, year = {2022}, month = {OCT}, pages = {127157}, type = {Article}, abstract = {

Rice is a major food crop cultivated around the globe. Specially scented rice varieties are of commercial importance but they are low-yielding. The rhizospheric microflora plays a significant role in improving yield and aroma. However, the core microbiome of the scented rice rhizosphere is comparatively less explored. Here, we analyzed the core microbiome associated with the rhizosphere of the scented (Ambemohar-157 and Dehradun basmati) in comparison with non-scented rice (Kolam and Arize 6444 Gold) cultivated at two different geoclimatic zones of India (Maharashtra and Uttarakhand) using the metagenomics approach. The alpha and beta diversity analysis showed that the microbial communities associated with scented and non-scented varieties significantly changes with respect to richness, diversity, and evenness. The taxonomic profiling revealed the variation in composition, diversity, and abundance of the microbiome in terms of phyla and genera associated with scented rice varieties over non-scented. The cluster analysis distinguishes the microbial communities based on their geographical positions. The core microbiome analysis revealed that scented rice rhizosphere shelters distinct and unique microbiota. 28.6 \% of genera were exclusively present only in the scented rice rhizosphere. The putative functional gene annotation revealed the high abundance of genes related to the biosynthesis of 2-acetyl-1-pyrroline (2AP) precursors in scented rice. The precursor feeding analysis revealed proline as a preferred substrate by 2AP synthesizing bacteria. The 2AP precursor proline and proline metabolism genes showed a positive correlation. The scented rice-specific rhizobacteria pointed out in this study can be used as bioinoculants for enhancing aroma, yield, and sustainable rice cultivation.

}, keywords = {Metagenome, Microbial community, Microbiome, Oryza sativa, Rhizosphere, rice}, issn = {0944-5013}, doi = {10.1016/j.micres.2022.127157}, author = {Dhondge, V. Harshal and Barvkar, Vitthal T. and Paul, Dhiraj and Dastager, Syed G. and Pable, Anupama A. and Nadaf, Altafhusain B.} } @article {48478, title = {Role of ions and their transporters in combating salt stress in Pandanus odorifer (Forssk.) Kuntze}, journal = {Acta Physiologiae Plantarum}, volume = {45}, year = {2023}, month = {MAY}, pages = {66}, type = {Article}, abstract = {

Soil salinity is a major environmental constraint causing huge losses in crop production. Pandanus odorifer (Forssk.) Kuntze is an aromatic monocot plant species belonging to the family Pandanaceae, which grows naturally on the saline soils along the coasts of Asia, Southeast Asia, and Polynesia. The plants are dioecious and highly fertile, and the consistent saline sprays, strong winds, and severe soil salinity hardly affect their growth and fertility. Hence, understanding the mechanism of high salinity tolerance in P. odorifer could provide major advances in overcoming salinity stress in crop plants. In the present study, we analyzed control (0 M NaCl) and treated (1 M NaCl treatment for 3 weeks) plants of P. odorifer to understand the role of ion distribution, ion transport, and related mechanisms under salt stress. Using a combination of ionomics and transcriptomics approaches, we identified the molecular mechanisms contributing to the high salinity stress in P. odorifer. Under NaCl stress, there was a significant increase in Na, Cl, and other ions in leaves, while the concentrations of Si, Fe, Ni, and Ti decreased. Similarly, in roots, the levels of Na, Mg, Cd, and Cr were significantly high, while the levels of other ions decreased. Most of the genes related to ion transport and homeostasis, such as NHX1, CLC-C, SOS1, HAK, and ABC transporters, were upregulated in 1 M NaCl stress conditions. This study revealed that vacuolar sequestration of Na+ and the distribution of ions in the roots and shoots play significant roles in the salt-stress tolerance mechanism of P. odorifer.

}, keywords = {Ion transport, Ionomics, Pandanus, Salinity tolerance, Transcriptomics, Vacuolar sequestration}, issn = {0137-5881}, doi = {10.1007/s11738-023-03541-8}, author = {Rashmi, Deo and Ansari, Waquar A. and Kadoo, Narendra Y. and Barvkar, Vitthal T. and Deshmukh, Rupesh and Nadaf, Altafhusain B.} } @article {49102, title = {Genome sequencing and protein modeling unraveled the 2AP biosynthesis in Bacillus cereus DB25}, journal = {International Journal of Food Microbiology}, volume = {413}, year = {2024}, month = {MAR }, pages = {110600}, type = {Article}, abstract = {

2-Acetyl-1-pyrroline (2AP) is an important and major flavor aroma compound responsible for the fragrance of basmati rice, cheese, wine, and several other food products. Biosynthesis of 2AP in aromatic rice and a few other plant species is associated with a recessive Betaine aldehyde dehydrogenase 2 (BADH2) gene. However, the literature is scant on the relationship between the functional BADH2 gene and 2AP biosynthesis in prokaryotic systems. Therefore, in the present study, we aimed to explore the functionality of the BADH2 gene for 2AP biosynthesis in 2AP synthesizing rice rhizobacterial isolate Bacillus cereus DB25 isolated from the rhizosphere of basmati rice (Oryza sativa L.). Full-length BcBADH2 sequence was obtained through whole genome sequencing (WGS) and further confirmed through traditional PCR and Sanger sequencing. Then the functionality of the BcBADH2 gene was evaluated in-silico through bioinformatics analysis and protein docking studies and further experimentally validated through enzyme assay. The sequencing and bioinformatics analysis results revealed a full-length 1485 bp BcBADH2 coding sequence without any deletion or premature stop codons. Full-length BcBADH2 was found to encode a fully functional protein of 54.08 kDa with pI of 5.22 and showed the presence of the conserved amino acids responsible for enzyme activity. The docking studies confirmed a good affinity between the protein and its substrate whereas the presence of BcBADH2 enzyme activity confirmed the functionality of BADH2 enzyme in B. cereus DB25. In conclusion, the findings of the present study suggest that B. cereus DB25 is able to synthesize 2AP despite a functional BADH2 gene and there may be a different molecular mechanism responsible for 2AP biosynthesis in bacterial systems, unlike that found in aromatic rice and other eukaryotic plant species.

}, keywords = {2-Acetyl-1-pyrroline, Basmati rice flavor, Betaine aldehyde dehydrogenase 2, Protein-ligand docking, Rhizobacteria, Whole-genome sequence}, issn = {0168-1605}, doi = {10.1016/j.ijfoodmicro.2024.110600}, author = {Dhondge, Harshal V. and Barvkar, Vitthal T. and Dastager, Syed G. and Dharne, Mahesh S. and Rajput, Vinay and Pable, Anupama A. and Henry, Robert J. and Nadaf, Altafhusain B.} }