Abstract
Soybean [Glycine max (L.) Merr.] is the leading oilseed crop which accounts for 60% of the global oilseed production. Soybean sudden death syndrome (SDS) is among the most important soil-borne fungal diseases that threaten soybean production in US. Rhizobia play an important role as a nitrogen source for soybean via the fixation of atmospheric nitrogen and its subsequent conversion to useable forms. Slow-growing Bradyrhizobium japonicum (BJ) is the best known species nodulating soybean. There are currently a few reports of the use of Bradyrhizobium spp. in row crop diseases management. In literature, Bradyrhizobium isolates successfully reduced symptoms of diseases caused by Macrophomina phaseolina, Fusarium solani, and Fusarium spp. However, to the best of our knowledge, no information on the role of Bradyrhizobium japonicum in the management of SDS is established. In view of this knowledge gap, this study was designed to: (i) determine the effects of B. japonicum seed treatments and/or soil inoculant on the incidence and severity of the SDS under controlled conditions; (ii) evaluate the effects of B. japonicum seed treatments on SDS under field conditions (irrigated and non-irrigated) To accomplish the first objective, two independent experiments were conducted twice under growth chambers and greenhouse conditions using a BJ strain from Iowa State University. Treated seeds (germinated or non-germinated) planted in clay pots or foam cups were exposed to three different growth chamber temperatures (15°C, 20°C and 25°C). Ten days later, treated seeds were shifted to a greenhouse at 25°C for the rest of study period. Treatments with BJ inoculated on the seeds planted in FV infested soil were found significantly effective in reducing SDS incidence and severity compared with untreated controls. In addition, BJ treatment of non-germinated or germinated seeds had significant influence on SDS incidence at low temperature. No significant effects on plant biomass were detected. To address the second objective, field trials were conducted during 2015 to 2017 cropping seasons using four BJ strains in seed treatments. At R6 (full seed set) growth stage, BJ treated plots showed lower SDS disease index compared with untreated plots in 2015 and 2016. Although no significant effects of treatments on nodule count and plant biomass, higher nodules count at V5 (fifth trifoliate) were observed in BJ treated plots compared with untreated plots. In addition, the BJ-treated plots showed yield advantage compared with untreated controls across three years. The results from these studies showed that B. japonicum can reduce SDS. Current findings also suggest that B. japonicum can be a potential biocontrol agent, which is environmentally friendly, and as one of the alternatives to soybean growers in Iowa
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. 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 7
Claim · model-written summary
BJ inoculated on seeds in Fusarium virguliforme infested soil significantly reduced SDS incidence and severity compared with untreated controls.
- Taxon
- soybean
Glycine maxt0 - Treatment
- BJ inoculated on the seedse0
- Interactor
- FVe0pathogen
- Second interactor
- BJe0biocontrol_agent
- Outcome
- SDS incidence and severitye0
- Direction
- reducinge0
- Comparator
- untreated controlse0
Not reportedValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e0“Treatments with BJ inoculated on the seeds planted in FV infested soil were found significantly effective in reducing SDS incidence and severity compared with untreated controls”
Claim · model-written summary
BJ treatment of non-germinated or germinated seeds had a significant influence on SDS incidence at low temperature.
- Taxon
- soybeanGlycine maxt0
- Treatment
- BJ treatment of non-germinated or germinated seedse1
- Outcome
- SDS incidencee1
- Qualifier
- at low temperaturee1
Not reportedComparatorDirectionValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e1“BJ treatment of non-germinated or germinated seeds had significant influence on SDS incidence at low temperature”
Claim · model-written summary
BJ seed inoculation had no significant effect on soybean plant biomass in the controlled experiments.
- Taxon
- soybeanGlycine maxt0
- Treatment
- BJ inoculated on the seedse0
- Outcome
- plant biomasse2
- Direction
- no_changeinferrede2
Not reportedComparatorValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e0“Treatments with BJ inoculated on the seeds planted in FV infested soil were found significantly effective in reducing SDS incidence and severity compared with untreated controls”
e2“No significant effects on plant biomass were detected”
Claim · model-written summary
In field trials at R6, BJ-treated plots showed lower SDS disease index than untreated plots in 2015 and 2016.
- Taxon
- soybeanGlycine maxt0
- Organ / stage
- R6 (full seed set) growth stagee3
- Treatment
- BJ treated plotse3
- Outcome
- SDS disease indexe3
- Direction
- lowere3
- Comparator
- untreated plotse3
- Setting
- field trialse4
Not reportedValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e3“At R6 (full seed set) growth stage, BJ treated plots showed lower SDS disease index compared with untreated plots in 2015 and 2016”
e4“field trials were conducted during 2015 to 2017 cropping seasons”
Claim · model-written summary
BJ-treated plots had higher nodule count at V5 than untreated plots in the field.
- Taxon
- soybeanGlycine maxt0
- Organ / stage
- V5 (fifth trifoliate)e5
- Treatment
- BJ treated plotse5
- Interactor
- BJe5symbiont
- Outcome
- nodules counte5
- Direction
- highere5
- Comparator
- untreated plotse5
Not reportedValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e5“higher nodules count at V5 (fifth trifoliate) were observed in BJ treated plots compared with untreated plots”
Claim · model-written summary
BJ-treated plots showed a soybean yield advantage over untreated controls across three years.
- Taxon
- soybeanGlycine maxt0
- Treatment
- BJ-treated plotse6
- Outcome
- yielde6
- Direction
- higherinferrede6
- Qualifier
- across three yearse6
- Comparator
- untreated controlse6
Not reportedValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e6“the BJ-treated plots showed yield advantage compared with untreated controls across three years”
Claim · model-written summary
Seed treatments with BJ had no significant effect on soybean nodule count or plant biomass in the field.
- Taxon
- soybeanGlycine maxt0
- Treatment
- treatmentse7
- Outcome
- nodule count and plant biomasse7
- Direction
- no_changeinferrede7
Not reportedComparatorValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“soybean sudden death syndrome”
e7“Although no significant effects of treatments on nodule count and plant biomass”
The same questions in other papers
Bradyrhizobium japonicum · growth · Glycine max (soybean)Results differ
2 papers in the same direction as this paper · 43 in the opposite direction
- positive
- positive
- positive
42 papers more in this group
See all 46 papers →inoculation · survival · Glycine max (soybean)Positive and negative results
4 papers in the same direction as this paper · 3 in the opposite direction
- negative
- negative
- negative
4 papers more in this group
See all 8 papers →inoculation · growth · Glycine max (soybean)Positive and negative results
34 papers in the same direction as this paper · 323 in the opposite direction
- positive
- positive
- positive
354 papers more in this group
See all 358 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.