Abstract
Oriental melon (Cucumis melo L.) is a popular Korean, Japanese, and Chinese fruit (Shin et al. 2017). In April 2022, abnormal fruit (n=20) that were collected in Sangju in Gyeongbuk Province (36°27'54.6"N, 128°10'49.7"E), Korea showed approximately 5% disease incidence with severity of 10-15%. Initial symptoms included shriveling, soaking, softening, dark discoloration, and sunken lesions. Internally, a rot extended to flesh, darkening from brown to black, and producing black mycelial masses. Two fungal strains (OM-rot-01 and OM-rot-02) were isolated and exhibited similar culture characteristics: aerial mycelium that was flat and pale grey to olivaceous on potato dextrose (PDA), malt extract (MEA), and oatmeal agar (OA) after seven days at 25°C and produced abundant buff-colored pycnidial ascomata on OA. Asci were bitunicate, clavate to cylindrical, 48.4 to 69.0 × 6.1 to 6.9 μm (n=10), and ascospores were biseriate, sparse, ellipsoidal, straight to slightly curved, hyaline, smooth, apex obtuse, 1-septate, 11.1 to 14.9 × 3.8 to 5.4 μm (n=20). Conidiomata were pycnidial, mostly solitary, irregular, pale brown to black, semi-immersed, 150 to 220 × 120 to 200 μm. Conidia were oblong or ovoid, smooth, thin-walled, hyaline, aseptate, 4.4 to 6.7 × 2.0 to 2.8 μm (n=35), with 1-3 guttules per conidium. The morphological characteristics corresponded to those of Stagonosporopsis cucumeris (Hou et al. 2020). For molecular identification, genomic DNA was extracted from strains (OM-rot-01 and OM-rot-02), and the ITS regions, partial 28S rDNA (LSU), beta-tubulin (TUB2), and RNA polymerase II second largest subunit (RPB2) genes were amplified and sequenced (White et al. 1990; Woudenberg et al. 2009; Vilgalys & Hester 1990; Liu et al. 1999). The obtained sequences revealed 99-100% homology with S. cucumeris accessions (MH858625, MH870265, MT005554, and MT018021). The sequences were deposited in GenBank with accession nos. for ITS regions (OP788058, OP788059), 28S rDNA (OP788094, OP788095), TUB2 (OP810568, OP810569), and RPB2 (OP810570, OP810571). Phylogenetic analysis combined with ITS, LSU, TUB2, and RPB2 concatenated sequences using neighbor-joining method revealed that the strains were S. cucumeris. To confirm pathogenicity, OM-rot-01 was inoculated onto ripe, asymptomatic Oriental melon fruit (n=6). After they were surface sterilized with 70% alcohol, fruit were wounded using a sterilized needle and corkborer, and 5-mm-diameter mycelial plugs were attached to the wound sites, followed by covering of the fruit with aluminum foil and maintenance in a plastic box (>90% relative humidity) at 25°C. Non-wounded fruit were inoculated and incubated in a similar manner, and fruit that were inoculated with PDA plugs served as controls (n=3). The aluminum foil was removed after three days of inoculation, and other conditions were kept constant. After six days, typical internal fruit rot symptoms were observed in both wounded and non-wounded fruit; brown to black rot extended into flesh, whereas control fruit remained asymptomatic. Fungi reisolated from lesions were morphologically identical to OM-rot-01; identity was confirmed by molecular analysis, fulfilling Koch's postulates, and the pathogenicity test was conducted three times. S. cucumeris was found as a canker on Cucumis sativus in the Netherlands (Hou et al. 2020), but has not been reported elsewhere as a pathogen on Cucumis spp. To our knowledge, this is the first report of S. cucumeris causing internal fruit rot on Oriental melon in Korea. This disease poses a threat to melon production, so accurate identification of the pathogen is a key starting point for development of sustainable management practices.
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 9
Claim · model-written summary
Abnormal Oriental melon fruit in Sangju showed about 5% disease incidence and 10–15% severity.
- Taxon
- Oriental Melon
.jpg?width=60)
Cucumis melot0 - Outcome
- disease incidencee0
- Value
- 5%e0
- Setting
- Sangju in Gyeongbuk Provincee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
.jpg?width=500)
Verbatim
e0“abnormal fruit (n=20) that were collected in Sangju in Gyeongbuk Province (36°27'54.6"N, 128°10'49.7"E), Korea showed approximately 5% disease incidence with severity of 10-15%”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
Affected fruit had external shriveling, soaking, softening, discoloration and sunken lesions.
- Taxon
- Oriental MelonCucumis melot0
- Outcome
- shriveling, soaking, softening, dark discoloration, and sunken lesionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Initial symptoms included shriveling, soaking, softening, dark discoloration, and sunken lesions.”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
Internal rot extended into the flesh and darkened from brown to black with black mycelial masses.
- Taxon
- Oriental MelonCucumis melot0
- Outcome
- rot extended to flesh, darkening from brown to black, and producing black mycelial massese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a rot extended to flesh, darkening from brown to black, and producing black mycelial masses”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
Morphology of the isolated fungus matched Stagonosporopsis cucumeris.
- Taxon
- Oriental MelonCucumis melot0
- Interactor
- Stagonosporopsis cucumerisStagonosporopsis cucumerise0pathogen
- Outcome
- morphological characteristics corresponded to those of Stagonosporopsis cucumerise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The morphological characteristics corresponded to those of Stagonosporopsis cucumeris”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
Isolate sequences had 99–100% homology with S. cucumeris accessions.
- Taxon
- Oriental MelonCucumis melot0
- Interactor
- S. cucumerisStagonosporopsis cucumerise0pathogen
- Outcome
- homology with S. cucumeris accessionse0
- Value
- 99-100%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The obtained sequences revealed 99-100% homology with S. cucumeris accessions”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
Concatenated-sequence phylogeny identified the strains as S. cucumeris.
- Taxon
- Oriental MelonCucumis melot0
- Interactor
- S. cucumerisStagonosporopsis cucumerise0pathogen
- Outcome
- strains were S. cucumerise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Phylogenetic analysis combined with ITS, LSU, TUB2, and RPB2 concatenated sequences using neighbor-joining method revealed that the strains were S. cucumeris.”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
Inoculated wounded and unwounded Oriental melon fruit developed internal fruit rot after six days while controls remained asymptomatic.
- Taxon
- Oriental melonCucumis meloe0
- Organ / stage
- fruite0
- Treatment
- OM-rot-01 was inoculatede0
- Outcome
- internal fruit rot symptomse1
- Comparator
- control fruite1
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“OM-rot-01 was inoculated onto ripe, asymptomatic Oriental melon fruit”
e1“After six days, typical internal fruit rot symptoms were observed in both wounded and non-wounded fruit; brown to black rot extended into flesh, whereas control fruit remained asymptomatic.”
Claim · model-written summary
The fungus reisolated from lesions matched OM-rot-01 morphologically and molecularly.
- Taxon
- Oriental MelonCucumis melot0
- Outcome
- morphologically identical to OM-rot-01e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fungi reisolated from lesions were morphologically identical to OM-rot-01; identity was confirmed by molecular analysis”
t0“Oriental Melon (Cucumis melo)”
Claim · model-written summary
The authors report S. cucumeris causing internal fruit rot on Oriental melon in Korea for the first time.
- Taxon
- Oriental melonCucumis meloe0
- Interactor
- S. cucumerisStagonosporopsis cucumerise0pathogen
- Outcome
- S. cucumeris causing internal fruit rote0
- Setting
- Koreae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“this is the first report of S. cucumeris causing internal fruit rot on Oriental melon in Korea”
The same questions in other papers
inoculation · disease · Cucumis melo (muskmelon)Positive and negative results
26 papers in the same direction as this paper · 13 in the opposite direction
- negative
- positive
- positive
36 papers more in this group
See all 40 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.