First Report of Leaf Spot Caused by Alternaria alternata on Ligustrum japonicum in China

Ligustrum japonicum is a small evergreen tree belonging to the Oleaceae and widely grown in China as a landscape ornamental and medicinal plant (Oh et al. 2021). In April 2021, a leaf spot disease was observed on Ligustrum japonicum in the campus of Anhui Agricultural University (31°51'4″N; 117...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Plant disease. - 1997. - (2022) vom: 06. Juni
1. Verfasser: Fang, Wei (VerfasserIn)
Weitere Verfasser: Shi, Shuping, Yin, Caiping, Zhang, Yinglao
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2022
Zugriff auf das übergeordnete Werk:Plant disease
Schlagworte:Journal Article Alternaria alternata Ligustrum japonicum leaf spot
LEADER 01000caa a22002652 4500
001 NLM341880965
003 DE-627
005 20240217231910.0
007 cr uuu---uuuuu
008 231226s2022 xx |||||o 00| ||eng c
024 7 |a 10.1094/PDIS-01-22-0068-PDN  |2 doi 
028 5 2 |a pubmed24n1297.xml 
035 |a (DE-627)NLM341880965 
035 |a (NLM)35666223 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Fang, Wei  |e verfasserin  |4 aut 
245 1 0 |a First Report of Leaf Spot Caused by Alternaria alternata on Ligustrum japonicum in China 
264 1 |c 2022 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Revised 16.02.2024 
500 |a published: Print-Electronic 
500 |a Citation Status Publisher 
520 |a Ligustrum japonicum is a small evergreen tree belonging to the Oleaceae and widely grown in China as a landscape ornamental and medicinal plant (Oh et al. 2021). In April 2021, a leaf spot disease was observed on Ligustrum japonicum in the campus of Anhui Agricultural University (31°51'4″N; 117°14'54″E), in Hefei City, Anhui Province, China. Approximately 50% of L. japonicum infections showed symptoms of round to oval, brown to dark brown lesions surrounded by a yellow halo. Diseased leaves were collected to determine the caused pathogen. Nine tissue pieces from three symptomatic leaves were surface sterilized with 2% NaClO for 1-2 minutes, followed by 75% ethanol for 1 minute, and then rinsed with sterile water for three times. The tissues samples were plated on potato dextrose agar(PDA)medium and incubated at 28 °C for 3 days. Seven fungal isolates were obtained from the plated tissues; the fungal hyphae were initially white and finally gray brown with flocculent aerial mycelia. Conidia were solitary or in chains, with various shapes, mostly subglobose. The size was (12.0-30.0) μm long and (6.0~12.0) μm wide (n=20). The cultural and morphological characteristics of these isolates were similar to those of Alternaria alternata (Simmons et al. 2007; Garibaldi et al. 2020). For accurate identification, genomic DNA was extracted from the mycelia of representative isolate (JSNZ). The internal transcribed spacer (ITS), 18S nrDNA (SSU), translation elongation factor 1-alpha (Tef1-α) and endopolygalacturonase (endoPG) sequences were amplified with the primer pairs of ITS1/ITS4, NS1/NS4, EFI-728F/EFI-986R and EPG-specific/EPG-3b, respectively (Woudenberg et al, 2013). The sequences were deposited in GeneBank under accessions MZ360963 (ITS), MZ677478 (SSU), OK274117(Tef1-α) and OK513186 (endoPG). BLAST analysis of the sequences of ITS, SSU, Tef1-α and endoPG showed >99% identity with those of A. alternata MK108918(561/601bp), KX609765 (1030/1035bp), LC132712 (281/281bp) and MT185591(459/483bp), respectively. A neighbor-joining phylogenetic tree was generated based on the concatenated data from sequences of ITS, SSU and Tef1-α using MEGA5.1, which clustered the present isolate with A. alternata strain CBS916.96 with high bootstrap support (100%). Based on cultural characteristics and phylogenetic analysis, the current isolate associated with leaf spot of L. japonicum was identified as A. alternata. Pathogenicity test was performed on three healthy L. japonicum on campus. Three healthy leaves of each plant were wounded with one sterile needle and inoculated with a 5-mm-diameter mycelial plug using sterile PDA plugs as control. The inoculated plants were covered with plastic bags and sprayed with water every 24 hours to maintain a high temperature and humidity environment. The experiment was repeated three times. After 12-days of incubation, symptoms were apparent on pathogen-inoculated plants, while the control plants remained asymptomatic. A. alternata was reisolated from inoculated leaves and matched the morphological and molecular characteristics of the original isolates, thus fulfilling Koch's postulates. To the best of our knowledge, this is the first report of a leaf spot disease caused by A. alternata in L. japonicum in China. Its identification will establish a foundation for managing the disease in China 
650 4 |a Journal Article 
650 4 |a Alternaria alternata 
650 4 |a Ligustrum japonicum 
650 4 |a leaf spot 
700 1 |a Shi, Shuping  |e verfasserin  |4 aut 
700 1 |a Yin, Caiping  |e verfasserin  |4 aut 
700 1 |a Zhang, Yinglao  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Plant disease  |d 1997  |g (2022) vom: 06. Juni  |w (DE-627)NLM098181742  |x 0191-2917  |7 nnns 
773 1 8 |g year:2022  |g day:06  |g month:06 
856 4 0 |u http://dx.doi.org/10.1094/PDIS-01-22-0068-PDN  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_350 
951 |a AR 
952 |j 2022  |b 06  |c 06