Abstract
Damping-off disease represents a considerable hazard to the cultivation of Chinese kale (Brassica oleracea var. alboglabra), leading to seedling death and notable economic repercussions. This study explores the efficacy of guava leaf extracts, obtained through different extraction solvents, against Pythium aphanidermatum, a significant pathogen causing damping-off disease in Chinese kale (Pak Kha-naa) cultivation in Thailand. Guava leaf extract was obtained using different solvents: hexane, ethyl acetate and ethanol. Subsequently, the extract was diluted to concentrations of 1,000, 1,500 and 3,000 ppm to assessment the inhibitory effects on P. aphanidermatum utilizing the poisoned plate technique. Results revealed that only ethanol-extracted guava leaf extract at 3,000 ppm exhibited significant inhibition of P. aphanidermatum, achieving complete inhibition. At 1,500 ppm, ethanol-extracted guava leaf extract demonstrated inhibition comparable to carbendazim. Greenhouse trials further confirmed the efficacy of pre-planting seeds coating with ethanolic guava leaf extract at concentrations of 1,500 and 3,000 ppm in reducing damping-off disease incidence in Chinese kale. Chemical analysis of guava extract with GC-MS revealed the presence of 58 compounds in the hexane extract, with copaene, β-caryophyllene, calamenene and caryophyllene oxide being major constituents. The ethyl acetate extract contained 53 compounds, including β-caryophyllene and squalene, while caryophyllene was a predominant component among the 40 chemicals identified in the ethanol extract. Methylparaben was exclusively present in the ethanol extract, showcasing inhibitory effects on the fungus. This research sheds light on the potential of guava leaf extracts as a sustainable solution for disease management in Chinese kale cultivation. HIGHLIGHTSEthanolic extract of guava leaf at 3,000 ppm completely inhibits the pathogen Pythium aphanidermatum. Seed coated with ethanol-extracted guava leaf extract at concentrations of 1,500 and 3,000 ppm reduced damping-off disease incidence in Chinese kale in greenhouse trials. Chemical analysis via GC-MS revealed diverse compounds in guava leaf extracts, with notable constituents such as copaene, β-caryophyllene, calamenene and caryophyllene oxide in the hexane extract, β-caryophyllene and squalene in the ethyl acetate extract and caryophyllene predominance in the ethanol extract. Identification of methylparaben exclusively in the ethanol extract suggests its potential inhibitory effects on the fungus. This study underscores the promising potential of guava leaf extracts as a sustainable solution for disease management in Chinese kale cultivation, offering insights into alternative methods for controlling damping-off disease. GRAPHICAL ABSTRACT
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Claims 9
Claim · model-written summary
Ethanol guava leaf extract at 3,000 ppm completely inhibited P. aphanidermatum.
- Taxon
- Chinese kale
Brassica oleracea var. alboglabrat0 - Treatment
- ethanol-extracted guava leaf extract at 3,000 ppme0
- Interactor
- P. aphanidermatumPythium aphanidermatume0pathogen
- Outcome
- P. aphanidermatume0
- Direction
- complete inhibitione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“only ethanol-extracted guava leaf extract at 3,000 ppm exhibited significant inhibition of P. aphanidermatum, achieving complete inhibition”
t0“Chinese Kale”
Claim · model-written summary
At 1,500 ppm ethanol guava extract inhibited the pathogen comparably to carbendazim.
- Taxon
- Chinese kaleBrassica oleracea var. alboglabrat0
- Treatment
- 1,500 ppm, ethanol-extracted guava leaf extracte0
- Interactor
- Pythium aphanidermatumPythium aphanidermatumt0pathogen
- Outcome
- inhibitione0
- Direction
- comparablee0
- Comparator
- carbendazime0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At 1,500 ppm, ethanol-extracted guava leaf extract demonstrated inhibition comparable to carbendazim”
t0“Pythium aphanidermatum, Chinese Kale”
Claim · model-written summary
Seed coating with ethanolic extract at 1,500 ppm reduced kale damping-off incidence in greenhouse trials.
- Taxon
- Chinese kaleBrassica oleracea var. alboglabrae0
- Treatment
- pre-planting seeds coating with ethanolic guava leaf extract at concentrations of 1,500 and 3,000 ppme0
- Interactor
- Pythium aphanidermatumPythium aphanidermatumt0pathogen
- Outcome
- damping-off disease incidencee0
- Direction
- reducinge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“pre-planting seeds coating with ethanolic guava leaf extract at concentrations of 1,500 and 3,000 ppm in reducing damping-off disease incidence in Chinese kale”
t0“Pythium aphanidermatum”
Claim · model-written summary
Hexane guava extract contained 58 compounds, with four major constituents.
- Taxon
- guava
Psidium guajavat0 - Treatment
- hexane extracte0
- Outcome
- 58 compoundse0
- Value
- 58e0
- Qualifier
- copaene, β-caryophyllene, calamenene and caryophyllene oxidee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“58 compounds in the hexane extract, with copaene, β-caryophyllene, calamenene and caryophyllene oxide being major constituents”
t0“Guava Leaf Extract”
Claim · model-written summary
Ethyl acetate guava extract contained 53 compounds including β-caryophyllene and squalene.
- Taxon
- guavaPsidium guajavat0
- Treatment
- ethyl acetate extracte0
- Outcome
- compoundse0
- Value
- 53e0
- Qualifier
- β-caryophyllene and squalenee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ethyl acetate extract contained 53 compounds, including β-caryophyllene and squalene”
t0“Guava Leaf Extract”
Claim · model-written summary
Ethanol guava extract had 40 identified chemicals, with caryophyllene predominant.
- Taxon
- guavaPsidium guajavat0
- Treatment
- ethanol extracte0
- Outcome
- chemicals identifiede0
- Direction
- predominante0
- Value
- 40e0
- Qualifier
- caryophyllenee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“caryophyllene was a predominant component among the 40 chemicals identified in the ethanol extract”
t0“Guava Leaf Extract”
Claim · model-written summary
Methylparaben occurred exclusively in the ethanol guava extract.
- Taxon
- guavaPsidium guajavat0
- Treatment
- ethanol extracte0
- Outcome
- Methylparaben was exclusively presente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Methylparaben was exclusively present in the ethanol extract”
t0“Guava Leaf Extract”
Claim · model-written summary
Methylparaben showed antifungal effects on the damping-off fungus.
- Taxon
- Chinese kaleBrassica oleracea var. alboglabrat0
- Interactor
- Pythium aphanidermatumPythium aphanidermatumt0pathogen
- Compound
- Methylparabene0
- Outcome
- inhibitory effects on the funguse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Methylparaben was exclusively present in the ethanol extract, showcasing inhibitory effects on the fungus”
t0“Pythium aphanidermatum, Chinese Kale”
Claim · model-written summary
The authors propose guava leaf extract for Chinese kale disease management.
- Taxon
- Chinese kaleBrassica oleracea var. alboglabrae0
- Outcome
- guava leaf extracts as a sustainable solution for disease managemente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This research sheds light on the potential of guava leaf extracts as a sustainable solution for disease management in Chinese kale cultivation.”
The same questions in other papers
botanical · Pythium aphanidermatum · Brassica oleracea (wild cabbage)Results agree
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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.