Abstract
ABSTRACT Chitosan (1 mg ml−1) reduced mycelial growth, sporangial production, release of zoospores and germination of cysts of metalaxyl resistance and sensitive Phytophthora infestans isolates. Treating tomato plants with chitosan (Img ml−1) 7 days before inoculation resulted in significant disease protection. Treatment of leaf no. 2 and 3, 7 days before inoculation induced resistance in leaf no. 4. Treatments 2–24 h after inoculation provided significant disease reduction compared with the control. Foliar application with chitosan caused small necrotic lesions on treated tomato leaves, which became visible 24 h after treatment, especially on adaxial leaf surfaces. Localized small lesions were characterized by cell death as demonstrated by irreversible uptake of Evans blue. Light and fluorescent microscopic examinations of leaf disks stained with trypan blue/Evans blue showed clusters of dead cells which were surrounded by cells exhibiting deposition of callóse. In chitosan treated tomato leaves, superoxide anion (O− 2,) generation was determined 12–36 h after treatment by nitroblue-tetrazolium staining and production of H2O2, was detected by 3,3- diaminbenzidine-4HCl staining 12–16 h after treatment. In treated tomato leaf tissues peroxidase activity increased with extending time after treatment. The highest activity was determined 48 h after treatment. Also, free and total salicylic acid contents significantly increased in chitosan treated leaves. Furthermore chitosan enhanced accumulation of pathogenesis related-proteins such as ß-1,3-glucanase, chitinase and PR 14 in treated and upper untreated tomato leaves. The studies with chitosan against tomato late blight suggested that chitosan displays dual effects: (a) direct interference in developmental stages of P. infestans and (b) by lesion formation, leading to disease resistance mechanisms.
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Claims 13
Claim · model-written summary
Chitosan reduced mycelial growth, sporangial production and zoospore release of resistant and sensitive Phytophthora infestans isolates.
- Taxon
- Tomato
Solanum lycopersicumt0 - Treatment
- Chitosan (1 mg ml−1)e0
- Interactor
- Phytophthora infestans
Phytophthora infestanse0pathogen - Outcome
- mycelial growth, sporangial production, release of zoosporese0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Chitosan (1 mg ml−1) reduced mycelial growth, sporangial production, release of zoospores and germination of cysts of metalaxyl resistance and sensitive Phytophthora infestans isolates”
t0“Tomato”
Claim · model-written summary
Chitosan reduced cyst germination of resistant and sensitive Phytophthora infestans isolates.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Chitosan (1 mg ml−1)e0
- Interactor
- Phytophthora infestansPhytophthora infestanse0pathogen
- Outcome
- germination of cystse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Chitosan (1 mg ml−1) reduced mycelial growth, sporangial production, release of zoospores and germination of cysts of metalaxyl resistance and sensitive Phytophthora infestans isolates”
t0“Tomato”
Claim · model-written summary
Chitosan applied seven days before inoculation significantly protected tomato plants from disease.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- chitosan (Img ml−1)e0
- Outcome
- disease protectione0
- Qualifier
- 7 days before inoculatione0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treating tomato plants with chitosan (Img ml−1) 7 days before inoculation resulted in significant disease protection”
Claim · model-written summary
Treating tomato leaves 2 and 3 before inoculation induced resistance in leaf 4.
- Taxon
- TomatoSolanum lycopersicumt0
- Organ / stage
- leaf no. 4e0
- Treatment
- Treatment of leaf no. 2 and 3e0
- Outcome
- resistance in leaf no. 4e0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatment of leaf no. 2 and 3, 7 days before inoculation induced resistance in leaf no. 4”
t0“Tomato”
Claim · model-written summary
Treatment 2–24 h after inoculation significantly reduced disease relative to the control.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- Treatments 2–24 h after inoculatione0
- Outcome
- disease reductione0
- Direction
- reductione0
- Comparator
- the controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments 2–24 h after inoculation provided significant disease reduction compared with the control”
t0“Tomato”
Claim · model-written summary
Foliar chitosan caused small necrotic lesions on tomato leaves, visible after 24 h especially on adaxial surfaces.
- Taxon
- tomatoSolanum lycopersicume0
- Organ / stage
- leavese0
- Treatment
- Foliar application with chitosane0
- Outcome
- small necrotic lesionse0
- Qualifier
- 24 h after treatmente0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Foliar application with chitosan caused small necrotic lesions on treated tomato leaves, which became visible 24 h after treatment, especially on adaxial leaf surfaces”
Claim · model-written summary
Small lesions contained dead cells surrounded by cells with callose deposits.
- Taxon
- TomatoSolanum lycopersicumt0
- Outcome
- clusters of dead cells which were surrounded by cells exhibiting deposition of callósee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“clusters of dead cells which were surrounded by cells exhibiting deposition of callóse”
t0“Tomato”
Claim · model-written summary
Chitosan-treated tomato leaves generated superoxide anion 12–36 h after treatment.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- chitosane0
- Outcome
- superoxide anion (O− 2,) generatione0
- Qualifier
- 12–36 h after treatmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In chitosan treated tomato leaves, superoxide anion (O− 2,) generation was determined 12–36 h after treatment”
Claim · model-written summary
Chitosan-treated tomato leaves produced H2O2 at 12–16 h after treatment.
- Taxon
- TomatoSolanum lycopersicumt0
- Outcome
- production of H2O2e0
- Qualifier
- 12–16 h after treatmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“production of H2O2, was detected by 3,3- diaminbenzidine-4HCl staining 12–16 h after treatment”
t0“Tomato”
Claim · model-written summary
Peroxidase activity increased with time after treatment and peaked at 48 h.
- Taxon
- tomatoSolanum lycopersicume0
- Outcome
- peroxidase activitye0
- Direction
- increasede0
- Value
- 48 he0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In treated tomato leaf tissues peroxidase activity increased with extending time after treatment. The highest activity was determined 48 h after treatment”
Claim · model-written summary
Free and total salicylic acid contents significantly increased in chitosan-treated leaves.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- chitosane0
- Outcome
- free and total salicylic acid contentse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“free and total salicylic acid contents significantly increased in chitosan treated leaves”
t0“Tomato”
Claim · model-written summary
Chitosan enhanced accumulation of β-1,3-glucanase, chitinase and PR 14 in treated and untreated upper tomato leaves.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- chitosane0
- Gene
- ß-1,3-glucanase, chitinase and PR 14e0
- Outcome
- accumulation of pathogenesis related-proteinse0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“chitosan enhanced accumulation of pathogenesis related-proteins such as ß-1,3-glucanase, chitinase and PR 14 in treated and upper untreated tomato leaves”
Claim · model-written summary
The authors propose that chitosan protects tomato through direct interference with pathogen development and lesion-triggered resistance.
- Taxon
- TomatoSolanum lycopersicumt0
- Treatment
- chitosane0
- Interactor
- P. infestansPhytophthora infestanse0pathogen
- Outcome
- disease resistance mechanismse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“chitosan displays dual effects: (a) direct interference in developmental stages of P. infestans and (b) by lesion formation, leading to disease resistance mechanisms”
t0“Tomato”
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See all 24 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.