Abstract
Abstract Downy mildew, caused by the oomycete pathogen Peronospora belbahrii , is a devastating foliar disease of basil in the United States and worldwide. Currently there are very few chemistries or organic choices registered to control this disease. In this study, two systemic acquired resistance ( SAR ) inducers, acibenzolar‐S‐methyl ( ASM ) and β‐aminobutyric acid ( BABA ), were evaluated for their in vitro effects on the pathogen, for their potential to control basil downy mildew in greenhouses, and for changes in peroxidase activity in basil plants treated with these two SAR inducers. No significant inhibition of sporangial germination was detected in water agar amended with ASM at concentrations lower than 100 mg/l or with BABA at concentrations lower than 500 mg/l. Efficacy of ASM and BABA in greenhouses varied depending on the rate, method and timing of application. The area under the disease progress curve ( AUDPC ) of disease severity was significantly reduced compared to the non‐treated control when ASM was sprayed (in all experiments) or drenched (in one out of two experiments) pre‐, or pre‐ + post‐inoculation at rates of 25–400 mg/l. Three weekly post‐inoculation sprays of ASM at the rate of 50 mg/l reduced AUDPC by 93.0 and 47.2% when started 3 and 7 days after inoculation ( DAI ), respectively. The AUDPC of disease severity was also significantly reduced when BABA was sprayed pre‐ + post‐inoculation at rates of 125–500 mg/l. According to the prediction using a log‐logistic function, 50% maximum disease protection was achieved at a concentration of 27.5 mg/l of ASM . Basil plants treated with these two SAR inducers and challenged with the pathogen showed significantly higher peroxidase activity than the non‐treated control at 8 DAI . Temporally, the highest activity of peroxidase was detected at 8 DAI , decreased at 15 DAI and waned further at 23 DAI .
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 10
Claim · model-written summary
ASM below 100 mg/l did not significantly inhibit pathogen sporangial germination in water agar.
- Taxon
- basil
Ocimum basilicume2 - Treatment
- ASM at concentrations lower than 100 mg/le0
- Interactor
- Peronospora belbahrii
.jpg?width=60)
Peronospora belbahriie1pathogen - Outcome
- sporangial germinatione0
- Direction
- No significant inhibitione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“No significant inhibition of sporangial germination was detected in water agar amended with ASM at concentrations lower than 100 mg/l”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
BABA below 500 mg/l did not significantly inhibit pathogen sporangial germination in water agar.
- Taxon
- basilOcimum basilicume2
- Treatment
- BABA at concentrations lower than 500 mg/le0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- sporangial germinatione0
- Direction
- No significant inhibitione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No significant inhibition of sporangial germination was detected in water agar amended with ASM at concentrations lower than 100 mg/l or with BABA at concentrations lower than 500 mg/l”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
ASM spray before or around inoculation significantly reduced disease severity AUDPC against untreated control.
- Taxon
- basilOcimum basilicume2
- Treatment
- ASM was sprayede0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- disease severitye0
- Direction
- reducede0
- Qualifier
- pre‐, or pre‐ + post‐inoculation at rates of 25–400 mg/le0
- Comparator
- non‐treated controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“AUDPC ) of disease severity was significantly reduced compared to the non‐treated control when ASM was sprayed (in all experiments) or drenched (in one out of two experiments) pre‐, or pre‐ + post‐inoculation at rates of 25–400 mg/l”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
ASM drench before or around inoculation significantly reduced disease severity AUDPC in one of two experiments.
- Taxon
- basilOcimum basilicume2
- Treatment
- drenchede0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- disease severitye0
- Direction
- reducede0
- Qualifier
- in one out of two experimentse0
- Comparator
- non‐treated controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“AUDPC ) of disease severity was significantly reduced compared to the non‐treated control when ASM was sprayed (in all experiments) or drenched (in one out of two experiments) pre‐, or pre‐ + post‐inoculation at rates of 25–400 mg/l”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
Three weekly ASM sprays beginning three days after inoculation reduced AUDPC by 93.0%.
- Taxon
- basilOcimum basilicume2
- Treatment
- Three weekly post‐inoculation sprays of ASM at the rate of 50 mg/le0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- AUDPCe0
- Direction
- reducede0
- Value
- 93.0e0
- Qualifier
- 3 and 7 days after inoculation ( DAI )e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three weekly post‐inoculation sprays of ASM at the rate of 50 mg/l reduced AUDPC by 93.0 and 47.2% when started 3 and 7 days after inoculation ( DAI ), respectively”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
Three weekly ASM sprays beginning seven days after inoculation reduced AUDPC by 47.2%.
- Taxon
- basilOcimum basilicume2
- Treatment
- Three weekly post‐inoculation sprays of ASM at the rate of 50 mg/le0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- AUDPCe0
- Direction
- reducede0
- Value
- 47.2%e0
- Qualifier
- 3 and 7 days after inoculation ( DAI )e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three weekly post‐inoculation sprays of ASM at the rate of 50 mg/l reduced AUDPC by 93.0 and 47.2% when started 3 and 7 days after inoculation ( DAI ), respectively”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
Pre and post inoculation BABA sprays significantly reduced disease severity AUDPC.
- Taxon
- basilOcimum basilicume2
- Treatment
- BABA was sprayed pre‐ + post‐inoculation at rates of 125–500 mg/le0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- AUDPC of disease severitye0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“AUDPC of disease severity was also significantly reduced when BABA was sprayed pre‐ + post‐inoculation at rates of 125–500 mg/l”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
A log logistic model predicted 50% maximum disease protection at 27.5 mg/l ASM.
- Taxon
- basilOcimum basilicume2
- Treatment
- 27.5 mg/l of ASMe0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- disease protectione0
- Value
- 50%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“50% maximum disease protection was achieved at a concentration of 27.5 mg/l of ASM”
e1“pathogen Peronospora belbahrii”
e2“disease of basil”
Claim · model-written summary
ASM and BABA treated, pathogen challenged basil had significantly higher peroxidase activity than untreated control at eight days after inoculation.
- Taxon
- BasilOcimum basilicume0
- Treatment
- these two SAR inducerse0
- Interactor
- Peronospora belbahriiPeronospora belbahriie1pathogen
- Outcome
- peroxidase activitye0
- Direction
- highere0
- Comparator
- non‐treated controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Basil plants treated with these two SAR inducers and challenged with the pathogen showed significantly higher peroxidase activity than the non‐treated control at 8 DAI”
e1“pathogen Peronospora belbahrii”
Claim · model-written summary
Peroxidase activity was highest at eight days after inoculation, then decreased at days 15 and 23.
- Taxon
- BasilOcimum basilicumt0
- Outcome
- activity of peroxidasee0
- Direction
- decreasede0
- Qualifier
- 8 DAI , decreased at 15 DAI and waned further at 23 DAIe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“highest activity of peroxidase was detected at 8 DAI , decreased at 15 DAI and waned further at 23 DAI”
t0“Basil”
The same questions in other papers
application · Peronospora belbahrii · Ocimum basilicum (basil)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 →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.