Abstract
• Bacillus velezensis KB21 promotes cucumber growth under optimal inoculation conditions. • B. velezensis KB21 enhances salt tolerance by modulating ion balance and antioxidant defenses. • B. velezensis KB21 upregulates stress-responsive and phytohormone biosynthesis genes. • Whole-genome analysis reveals genes linked to plant growth and stress adaptation. • B. velezensis KB21 shows promise as a biofertilizer for sustainable agricultural practices. This study investigates the genomic and functional traits of Bacillus velezensis KB21, a plant growth–promoting rhizobacterium, and its effects on cucumber ( Cucumis sativus ) growth and salt stress tolerance. Whole–genome sequencing revealed a 4.12 Mb circular chromosome with 27 rRNA genes, 86 tRNA genes, and 4,015 coding sequences, including those involved in auxin (IAA), gibberellin (GA), and volatile organic compound biosynthesis. Inoculation at optimal concentration (log 5 and log 3 CFU/mL) significantly enhanced cucumber growth, increasing fresh and dry biomass, leaf area, and root colonization. Growth promotion was linked to the enhanced expression of CsSAUR50 and CsGA20ox , which regulate auxin and GA biosynthesis during seed germination. Under salt stress conditions, KB21–treated plants showed improved growth, a favorable Na + /K + ratio, and increased antioxidant enzyme activities (SOD, POD, and CAT). The treatment upregulated stress–responsive genes, including HKT, NHX , and AQP , and ABA–related genes ( CsNCED1 and CsCYP707A1 ), demonstrating its role in ion homeostasis and ABA–mediated stress adaptation. These findings highlight the potential of B. velezensis KB21 as a sustainable biofertilizer for enhancing plant growth and resilience under abiotic stress conditions
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc-nd. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 12
Claim · model-written summary
Inoculation with B. velezensis KB21 at optimal concentration increased fresh and dry biomass and leaf area of cucumber.
- Taxon
- cucumber
Cucumis sativust0 - Treatment
- Inoculation at optimal concentration (log 5 and log 3 CFU/mL)e1
- Interactor
- Bacillus velezensis KB21
Bacillus velezensist1symbiont - Outcome
- fresh and dry biomass, leaf areae1
- Direction
- increasinge1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
t1“Bacillus velezensis KB21”
e1“Inoculation at optimal concentration (log 5 and log 3 CFU/mL) significantly enhanced cucumber growth, increasing fresh and dry biomass, leaf area, and root colonization”
Claim · model-written summary
Inoculation with B. velezensis KB21 at optimal concentration increased root colonization of cucumber.
- Taxon
- cucumberCucumis sativust0
- Treatment
- Inoculation at optimal concentration (log 5 and log 3 CFU/mL)e1
- Interactor
- Bacillus velezensis KB21Bacillus velezensist1symbiont
- Outcome
- root colonizatione1
- Direction
- increasinge1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
t1“Bacillus velezensis KB21”
e1“Inoculation at optimal concentration (log 5 and log 3 CFU/mL) significantly enhanced cucumber growth, increasing fresh and dry biomass, leaf area, and root colonization”
Claim · model-written summary
The B. velezensis KB21 genome has a 4.12 Mb circular chromosome.
- Taxon
- cucumberCucumis sativust0
- Outcome
- circular chromosomee2
- Value
- 4.12 Mbe2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e2“Whole–genome sequencing revealed a 4.12 Mb circular chromosome with 27 rRNA genes, 86 tRNA genes, and 4,015 coding sequences”
Claim · model-written summary
The B. velezensis KB21 genome contains 27 rRNA genes.
- Taxon
- cucumberCucumis sativust0
- Outcome
- rRNA genese2
- Value
- 27e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e2“Whole–genome sequencing revealed a 4.12 Mb circular chromosome with 27 rRNA genes, 86 tRNA genes, and 4,015 coding sequences”
Claim · model-written summary
The B. velezensis KB21 genome contains 86 tRNA genes.
- Taxon
- cucumberCucumis sativust0
- Outcome
- tRNA genese2
- Value
- 86e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e2“Whole–genome sequencing revealed a 4.12 Mb circular chromosome with 27 rRNA genes, 86 tRNA genes, and 4,015 coding sequences”
Claim · model-written summary
The B. velezensis KB21 genome contains 4,015 coding sequences.
- Taxon
- cucumberCucumis sativust0
- Outcome
- coding sequencese2
- Value
- 4,015e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e2“Whole–genome sequencing revealed a 4.12 Mb circular chromosome with 27 rRNA genes, 86 tRNA genes, and 4,015 coding sequences”
Claim · model-written summary
Under salt stress, KB21 treatment improved cucumber growth.
- Taxon
- cucumberCucumis sativust0
- Treatment
- salt stress conditionse4
- Interactor
- Bacillus velezensis KB21Bacillus velezensist1symbiont
- Outcome
- growthe4
- Direction
- improvede4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
t1“Bacillus velezensis KB21”
e4“Under salt stress conditions, KB21–treated plants showed improved growth, a favorable Na + /K + ratio, and increased antioxidant enzyme activities (SOD, POD, and CAT)”
Claim · model-written summary
Under salt stress, KB21-treated cucumber plants had a favorable Na+/K+ ratio.
- Taxon
- cucumberCucumis sativust0
- Treatment
- salt stress conditionse4
- Outcome
- Na + /K + ratioe4
- Direction
- favorablee4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e4“Under salt stress conditions, KB21–treated plants showed improved growth, a favorable Na + /K + ratio, and increased antioxidant enzyme activities (SOD, POD, and CAT)”
Claim · model-written summary
Under salt stress, KB21-treated cucumber plants showed increased antioxidant enzyme activities (SOD, POD and CAT).
- Taxon
- cucumberCucumis sativust0
- Treatment
- salt stress conditionse4
- Outcome
- antioxidant enzyme activities (SOD, POD, and CAT)e4
- Direction
- increasede4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e4“Under salt stress conditions, KB21–treated plants showed improved growth, a favorable Na + /K + ratio, and increased antioxidant enzyme activities (SOD, POD, and CAT)”
Claim · model-written summary
KB21 treatment upregulated stress-responsive genes HKT, NHX and AQP in cucumber.
- Taxon
- cucumberCucumis sativust0
- Treatment
- The treatmente5
- Gene
- HKT, NHX , and AQPe5
- Outcome
- stress–responsive genese5
- Direction
- upregulatede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e5“The treatment upregulated stress–responsive genes, including HKT, NHX , and AQP , and ABA–related genes ( CsNCED1 and CsCYP707A1 )”
Claim · model-written summary
KB21 treatment upregulated ABA-related genes CsNCED1 and CsCYP707A1 in cucumber.
- Taxon
- cucumberCucumis sativust0
- Treatment
- The treatmente5
- Gene
- CsNCED1 and CsCYP707A1e5
- Outcome
- ABA–related genese5
- Direction
- upregulatede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e5“The treatment upregulated stress–responsive genes, including HKT, NHX , and AQP , and ABA–related genes ( CsNCED1 and CsCYP707A1 )”
Claim · model-written summary
Growth promotion in cucumber was linked to enhanced expression of CsSAUR50 and CsGA20ox.
- Taxon
- cucumberCucumis sativust0
- Gene
- CsSAUR50 and CsGA20oxe3
- Outcome
- expressione3
- Direction
- enhancede3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“stress tolerance in cucumber”
e3“Growth promotion was linked to the enhanced expression of CsSAUR50 and CsGA20ox”
The same questions in other papers
salinity · soil: biology · Cucumis sativus (cucumber)Positive and negative results
2 papers in the same direction as this paper · 1 in the opposite direction
- negative
- positive
- positive
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.