Abstract
Abstract Background Soils affected by salinity are a recurring problem that is continually increasing due to the impact of climate change on weather conditions and ineffective agricultural management practices. The use of plant growth promoting (PGP) Bacteria can alleviate its effects. In this regard, the genus Rhizobium has demonstrated excellent PGP capabilities through various plant growth promotion mechanisms and may therefore be a promising biofortifier under saline conditions. However, little is known about the production of volatile organic compounds (VOCs) by bacteria of this genus and their effects on plant development. Here, we aim to characterize the volatilome (the set of volatile metabolites synthesized by an organism) of Rhizobium for the first time and to further investigate the direct and VOC-mediated interaction between a strain of this genus and lettuce, a crop severely affected by salinity, both under saline and non-saline conditions. Results In this study, it was shown that the use of Rhizobium sp. GPTR29 was able to increase the production of lettuce ( Lactuca sativa L.) under normal and saline conditions. We analyzed the Rhizobium volatilome under non-saline (0 mM NaCl) and saline (100 mM NaCl) conditions by HS-SPME-GC‒MS and found a differential composition in response to salinity. We detected 20 different compounds, where 3-methyl-1-butanol, 2-methyl-1-butanol, and α-pinene were the backbone of the Rhizobium volatilome. Exposure to these compounds in bicameral plates under salt stress resulted in increases in plant development of 17.1%, 16.0% and 33.1% in aerial part size, number of leaves and root length, respectively. Under greenhouse conditions and salinity, the inoculation of Rhizobium sp. GPTR29 resulted in an increase of 17.8% and 27.4% in shoot fresh and dry weight, respectively. Phenolic compounds were analyzed by HPLC–DAD-MS, revealing an increase in total flavonoid content under salinity conditions (100 mM NaCl) and apigenin derivative, luteolin 7- O -glucoside and quercetin 3- O -glucuronide individually. Conclusions These results provide new avenues for the study of PGP mechanisms in this bacterial genus, such as VOCs and their effects on plant growth, which play an important role in mediating plant–microorganism interactions. Graphical abstract
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. 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 11
Claim · model-written summary
Rhizobium sp. GPTR29 increased lettuce production under normal and saline conditions.
- Taxon
- lettuce
Lactuca sativae0 - Treatment
- the use of Rhizobium sp. GPTR29e0
- Interactor
- Rhizobium sp. GPTR29e0symbiont
- Outcome
- production of lettucee0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the use of Rhizobium sp. GPTR29 was able to increase the production of lettuce ( Lactuca sativa L.) under normal and saline conditions”
Claim · model-written summary
Rhizobium volatilome composition differed in response to salinity.
- Taxon
- lettuceLactuca sativat0
- Treatment
- salinitye0
- Outcome
- differential compositione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“found a differential composition in response to salinity”
Claim · model-written summary
Twenty compounds were detected in the Rhizobium volatilome.
- Taxon
- lettuceLactuca sativat0
- Outcome
- Rhizobium volatilomee0
- Value
- 20 different compoundse0
RhizobiumOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“We detected 20 different compounds, where 3-methyl-1-butanol, 2-methyl-1-butanol, and α-pinene were the backbone of the Rhizobium volatilome”
Claim · model-written summary
3-methyl-1-butanol, 2-methyl-1-butanol, and α-pinene formed the backbone of the Rhizobium volatilome.
- Taxon
- lettuceLactuca sativat0
- Outcome
- 3-methyl-1-butanol, 2-methyl-1-butanol, and α-pinenee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“3-methyl-1-butanol, 2-methyl-1-butanol, and α-pinene were the backbone of the Rhizobium volatilome”
Claim · model-written summary
Volatile exposure under salt stress increased lettuce aerial part size by 17.1%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- Exposure to these compoundse0
- Outcome
- aerial part sizee0
- Direction
- increasese0
- Value
- 17.1%e0
- Setting
- bicameral platese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“Exposure to these compounds in bicameral plates under salt stress resulted in increases in plant development of 17.1%, 16.0% and 33.1% in aerial part size, number of leaves and root length, respectively”
Claim · model-written summary
Volatile exposure under salt stress increased lettuce leaf number by 16.0%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- Exposure to these compoundse0
- Outcome
- number of leavese0
- Direction
- increasese0
- Value
- 16.0%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“Exposure to these compounds in bicameral plates under salt stress resulted in increases in plant development of 17.1%, 16.0% and 33.1% in aerial part size, number of leaves and root length, respectively”
Claim · model-written summary
Volatile exposure under salt stress increased lettuce root length by 33.1%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- Exposure to these compoundse0
- Outcome
- root lengthe0
- Direction
- increasese0
- Value
- 33.1%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“Exposure to these compounds in bicameral plates under salt stress resulted in increases in plant development of 17.1%, 16.0% and 33.1% in aerial part size, number of leaves and root length, respectively”
Claim · model-written summary
Rhizobium inoculation under greenhouse salinity increased shoot fresh weight by 17.8%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- inoculation of Rhizobium sp. GPTR29e0
- Interactor
- Rhizobium sp. GPTR29e0symbiont
- Outcome
- shoot freshe0
- Direction
- increasee0
- Value
- 17.8%e0
- Setting
- greenhouse conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“Under greenhouse conditions and salinity, the inoculation of Rhizobium sp. GPTR29 resulted in an increase of 17.8% and 27.4% in shoot fresh and dry weight, respectively”
Claim · model-written summary
Rhizobium inoculation under greenhouse salinity increased shoot dry weight by 27.4%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- inoculation of Rhizobium sp. GPTR29e0
- Interactor
- Rhizobium sp. GPTR29e0symbiont
- Outcome
- dry weighte0
- Direction
- increasee0
- Value
- 27.4%e0
- Setting
- greenhouse conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“Under greenhouse conditions and salinity, the inoculation of Rhizobium sp. GPTR29 resulted in an increase of 17.8% and 27.4% in shoot fresh and dry weight, respectively”
Claim · model-written summary
Total flavonoid content increased under 100 mM NaCl salinity.
- Taxon
- lettuceLactuca sativat0
- Treatment
- salinity conditions (100 mM NaCl)e0
- Outcome
- total flavonoid contente0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“revealing an increase in total flavonoid content under salinity conditions (100 mM NaCl)”
Claim · model-written summary
Apigenin derivative, luteolin 7- O -glucoside and quercetin 3- O -glucuronide increased individually under salinity.
- Taxon
- lettuceLactuca sativat0
- Treatment
- salinity conditions (100 mM NaCl)e0
- Outcome
- apigenin derivative, luteolin 7- O -glucoside and quercetin 3- O -glucuronidee0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“lettuce plants”
e0“an increase in total flavonoid content under salinity conditions (100 mM NaCl) and apigenin derivative, luteolin 7- O -glucoside and quercetin 3- O -glucuronide individually”
The same questions in other papers
sodium chloride · molecular: metabolites · Lactuca sativa (garden lettuce)Positive and negative results
1 paper in the same direction as this paper · 2 in the opposite direction
- negative
- no effect
- positive
Rhizobium · growth · Lactuca sativa (garden lettuce)Results agree
2 papers in the same direction as this paper
- positive
- positive
sodium chloride · quality: phytochemicals · Lactuca sativa (garden lettuce)Results agree
2 papers in the same direction as this paper
- positive
- positive
salinity · quality: phytochemicals · Lactuca sativa (garden lettuce)Positive and negative results
4 papers in the same direction as this paper · 1 in the opposite direction
- positive
- no effect
- positive
2 papers more in this group
See all 6 papers →salinity · molecular: metabolites · Lactuca sativa (garden lettuce)Positive and negative results
4 papers in the same direction as this paper · 7 in the opposite direction
- negative
- negative
- negative
8 papers more in this group
See all 12 papers →inoculation · growth · Lactuca sativa (garden lettuce)Positive and negative results
96 papers in the same direction as this paper · 12 in the opposite direction · 2 reporting no difference from an alternative
- no effect
- negative
- negative
107 papers more in this group
See all 111 papers →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.