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Dalbergia odorifera T. Chen (Family: Fabaceae) is an endangered, wild and second class key protected tree species in China. It has been cultivated widely in south China because of its valuable rosewood and pharmacological uses. During January and September 2022, anthracnose was observed on D. odorifera in Chikan, Zhanjiang, Guangdong (N21°15' 9.4" E110°22' 25.9"). All of the D. odorifera plants were infected and the leaf disease incidence was above 30%. The lesions were 0.35 to 0.65 cm in size, greyish-white, and gradually expanded into brown black circular spots surrounded by a yellowish halo. Later, the centers of spots were white with dark-brown borders. In severe cases, the leaves turned yellow, withered and fell off. To isolate the pathogen, about 5×5 mm tissues at the disease-health junction of spots were sterilized with 75% ethanol for 30s and 3% hydrogen peroxide for 3 min, rinsed with sterile water three times, and plated onto PDA for incubation at 25-28℃ in the dark. Isolates were obtained by picking the tip of hypha growing from the tissues, further purified by coating the diluted spore suspension to obtain single-spore isolates. Colonies with abundant aerial mycelium were white to light gray, 4.0 to 5.0 cm in diameter after 5 days at 25 to 28℃ in the dark. Conidiogenous cells were hyaline, cylindrical and monoblastic. Conidia were unicellular, subcylindrical, hyaline, guttulate, 3.5 to 5.6×11.1 to 16.8 (av. 4.6±0.48 × 14.0±1.25) μm (n>50). Appressoria were dark brown subglobose, clavate, fusiform, occasionally lobed, terminal, 7.8 to 16.3×4.6 to 8.9 μm. No swollen cells and setae were observed. To further confirm identity of the fungus, partial regions of six genetic loci of isolate ACCC 35246 (stored in Agricultural Culture Collection of China) were amplified and sequenced: actin (ACT), chitin synthase (CHS), glyceraldehyde-3-phosphate dehydrogenase (GPDH), histone (HIS), beta-tubulin (TUB) and internal transcribed spacer (ITS) utilizing the primer pairs (Damm et al. 2012; Weir et al. 2012; White et al 1990) (OP314900-OP314904 and OP269660, respectively). Based on a BLAST analysis, the six sequences were about 99% identical to those of Colletotrichum tropicale holotype strain CBS124949 (ACT: JX009489 270/272; CHS: JX009870 295/299; GPDH: JX010007 274/279; HIS: KY856395 638/670; ITS: JX010264 546/548 and TUB: JX010407 494/497, respectively) (Weir et al. 2012). Phylogenetic analyses, using a combined dataset of ACT, CHS, GPDH, ITS and TUB were carried out in MEGA X using the maximum likelihood method, placed the fungus within the C. tropicale clade. Based on morphogical and molecular analyses, the fungus was identified as C. tropicale (Rojas et al 2010). To test the pathogenicity, five healthy leaves of 1 year-old potted plants were stab-wounded with a sterile needle and inoculated with 10 µL of spore suspension (105 conidia/mL). Another five healthy leaves were inoculated with sterile water as the control. Symptoms expressed by the inoculated leaves, 10 days after inoculation, were the same as those of the diseased plants, while the non-inoculated leaves remained asymptomatic. The same fungus based on morphogical and molecular criteria was re-isolated from the spots. As an endophyte or plant pathogen, C. tropicale inhabits a wide host range of plant species belonging to 31 genera in 25 families (Farr and Rossman 2022), D. odorifera is a new host of C. tropicale causing anthracnose in China. This work will be helpful for the diagnosis and control of this disease.

Ficus religiosa L., known as bodhi tree, is an ornamental tree and widely planted as an avenue and roadside tree due to ovate-rounded leaves with narrow, elongated tips. During 2018-2021, circular to oval-shaped leaf spots with pale white centers and brown-black edges surrounded by a chlorotic halo were observed on the leaves of more than 200 bodhi trees all year round in a park in Zhanjiang, Guangdong (N 21°15'22.29''; E110°23'1.03''). The leaf disease incidences were usually 15-80%, in severe cases, up to 100% in autumn and winter every year, and some trees shed all leaves(Fig S1). Repeated annual defoliation may weaken the tree and decrease the aesthetic value in the landscape. Diseased tissues (5 × 5 mm) of five symptomatic infected leaves were surface sterilized in 3% hydrogen peroxide solution for 3 min, rinsed thrice with sterile water, plated on potato dextrose agar (PDA) amended with ampicillin (50mg/L), and incubated at 25-28 ℃ in the dark for 3-7 days. Five strains with similar morphology were obtained by transferring hyphal tips of the colonies to fresh PDA and further isolating by single spore method. Fungal colonies were flat and spreading, with sparse, white aerial mycelium, and black pycnidial conidiomata semi-immersed in PDA after 30-days incubation at 25-28 ℃ in dark. Conidiophores were hyaline and α-conidia were single-celled, oval to fusiform, guttulate, 5.3 × 2.5 μm (n50), similar to Diaporthe sp. (Crous et al. 2015), but no β and γ -conidia were observed. The internal transcribed spacer(ITS), large subunit ribosomal RNA gene(LSU), calmodulin (CAL) and β-tubulin(TUB) gene regions of a representative strain were amplified using specific primers reported by White et al. (1990), Gao et al (2017) and Gomes et al (2013), and submitted to GenBank (ITS: OM200852, LSU: OM228732, CAL: OM244761, TUB: OM244760). NCBI Blastn showed above 99% identity to D. tulliensis (anamorph: Phomopsis heveicola ) isolates of ITS (MT974186, MN393590 and KX457967), LSU (KR936131), CAL (MW759801), and TUB (KR936132 and MN399886), respectively (Crous et al. 2015; Huang et al. 2021; Gong et al. 2020; Bai et al. 2017). Based on the concatenated ITS, CAL, and TUB, a Maximum Likelihood phylogenetic analyses using MEGA 10.1.8 clustered the fungus with D. tulliensis in a clade with a 93% bootstrap support(Fig S2). Therefore, the fungus was identified as D. tulliensis based on morpho- molecular characteristics. Healthy detached leaves were sanitized thrice with 70% alcohol, and rinsed with sterile water. PDA plugs with actively growing 10-days-old mycelium were placed on predetermined sites, put into a sealed box with above 80% relative humidity and incubated at room temperature (25-28℃). Each isolate was inoculated at 25 needle-wounded and unwounded sites, PDA plugs without mycelium served as controls. Symptomatic spots appeared on all wounded leaves by 7 days post-inoculation (dpi) and on all unwounded leaves by 12 dpi. No symptoms appeared on controlled leaves. Pure cultures were recovered from inoculated leaves and showed identical morpho-molecular criteria to the original isolates. More than 70 pathogenic fungi are known to cause diseases on F. religiosa while there is no record of D. tulliensis infecting bodhi according to the U.S. National Fungus Collection (Farr and Rossman 2022). This report could provide basic understanding and alerting role for horticulturist in daily management.

Pennisetum sinese Roxb, named king grass or 'sugarcane grass', belonging to the Poaceae family, is widely cultivated in China because of its use for livestock feed, bioenergy, water-soil conservation and phytoremediation. In September 2018, leaf blast on P. sinese was observed in a pasture in Zhanjiang, Guangdong province (21.15°N, 110.30°E ). The lesions initially were round, water-soaked, oval or spindle-shaped, then later turned to typical eye-shaped, whitish in the center with brown-black necrotic borders surrounded by a yellow halo (Fig. S1). Almost all of plants were infected and most of the spots appeared on the blades in the lower part of the plants. The leaves gradually turned yellow and withered, which affected the growth and quality of the herbage. Diseased leaves were surface-sterilized with 75% ethanol for 30s, followed by 3% hydrogen peroxide solution for 3 mins, and rinsed three times with sterile water, then placed in a hermetic container with moistened filter paper, and kept at 21-24℃ to stimulate conidiogenesis. After conidiation, conidial suspensions were prepared with sterile water and evenly spread onto PDA, and incubated at 25 ℃ in the dark to collect single-spore isolates. Colonies on PDA were fuscous black with grey centers, broad white and flat. Conidiophores were solitary, erect, straight or curved, unbranched, medium brown, smooth, 2 septate, and sometimes up to 5 septate. Conidia with a protruding and truncating hilum on basal-cells were pyriform to obclavate, 2 septate, 22.2-28.8 × 7.1-9.6 μm ( 24.9±1.7 × 8.5±0.6 μm) (Fig S2). The internal transcribed spacer region (ITS), nrRNA gene large subunit (LSU), actin gene (ACT) and RNA polymerase II largest subunit gene (RPB2) were PCR amplified, and the amplicons were sequenced by Sangon Biotech (Shanghai) Co., Ltd. (ITS: OM294657, LSU: OM294656, ACT: OM304642, RPB2: OM304643). BLASTn result showed above 99% nucleotide identity with the ITS (KM484935 465/465 bp), LSU (MH412641 862/863 bp), ACT (XM_029891619 418/421 bp) and RPB2 (XM_029892603 894/898 bp) of Pyricularia pennisetigena strains. Maximum likelihood (ML) analysis based on ITS using MEGA revealed that the fungal isolate clustered in P. pennisetigena clade with 99% bootstrap support (Fig S3). Based on morpho-molecular criteria, the fungus was identified as P. pennisetigena (Klaubauf et al., 2014; Gómez Luciano et al, 2019; Wang et al., 2019). Four healthy leaves of a 2-month-old plant were surface disinfected, and 2 leaves were wounded with a sterile needle (3 wound sites each leaf), then one leaf was inoculated with 10 μl 105 conidia/ml suspension on each site, and on the other leaf, sterile water was used as the control inoculation. The similar inoculations were conducted on the other 2 unwounded leaves. Pathogenicity tests were repeated three times. Seven days later, all inoculated leaves (wounded and unwounded) showed typical symptoms, while no symptoms were observed with the controls on both the wounded and unwounded leaves. The same fungus was recovered and confirmed by morphology and the ITS and LSU sequences. P. pennisetigena is pathogenic on a wide range of Poaceae plants in Brazil, Japan, Mali, Philippines, United States, China (Klaubauf et al., 2014; Reges et al., 2016, Wang et al., 2019). Han et al (2020) reported bacterial leaf blast on king grass while this is first report of P. pennisetigena causing leaf blast. This finding is a warning to prevent and control of this disease and its infectivity to Poaceae plants.

Ophiopogon jaburan (Liliaceae), named white lilyturf, is widely cultivated as an ornamental plant in south China. During 2017-2019, leaf spots on O. jaburan were observed all year in Zhanjiang, Guangdong, China (N21°9'3"; E110°17'47"). Almost all plants were infected and the disease incidence on affected leaves was about 80% in the field. Initially, spots were brown, round or oval, and gradually enlarged to irregular shapes. The color of the spots changed from rusty-brown to grayish-white with rusty-brown borders. Subsequently, the spots expanded until the leaves withered and died. Infected tissues were surface-sterilized with 75% ethanol for 30s followed by 1% NaClO solution for 1 min, then rinsed thrice with sterile water, before placed on potato dextrose agar (PDA) containing 50mg/L ampicillin, and incubated in darkness at 25℃ with 90% relative humidity. Colonies growing on PDA were cushion-like, pale greenish grey to grayish black on the front side and clearly dark gray on the reverse. Colony diameter was av. 86.0 mm (n = 15) grown in the dark at 25 ℃ for 10 days. Conidia with oil droplets were colorless, hyaline, smooth-walled, aseptate, slightly curved, and tapered gradually to each end, 12.3-28.9 × 2.2-6.6 μm (av. 20.9×4.2μm, n=200). Setae were brown to dark brown, 2-4 septate, with the base slightly inflated, and measured 40.0-130.3 × 2.2-5μm (av. 84.3 × 3.3μm, n=23). On PDA, scattered or loosely clustered appressoria were elliptical or irregular, smooth-walled, aseptate, and dark brown. To confirm the identification, partial regions of the internal transcribed spacer (White et al. 1990), beta-tubulin (Aveskamp et al. 2009) and actin (Carbone et al 1999) were amplified and sequenced (MW989743, MZ014461 and MZ014462). The blast results showed these sequences had99.59% homology with sequences of Colletotrichum liriopes holotype strain CBS 119444 (NR_111449, GU228098 and GU227902). Maximum likelihood analysis and Bayesian inference were performed from concatenated sequences using RAxML v.1.0.0 and MrBayes v.3.2.1 software respectively. Several C. liriopes strains clustered in the same clade. Based on morphological-molecular characteristics, the fungus was identified as C. liriopes (Damm et al 2009; Chen et al. 2019). To confirm pathogenicity, healthy leaves were surface disinfected with 75% ethanol and rinsed thrice with sterile water. On ten leaves, three sites were wounded by pricking with needles, and inoculated 20 μL of 106 conidia/ml suspension or mycelium in contact with blade surface using 6-mm mycelial plugs. Similarly, the inoculation was done for three unwounded sites each leaf. Sterile water and medium plugs (without fungus) served as controls. All leaves were incubated on sterile wet filter paper at 25-28℃ with 90% relative humidity. After 7 days, all the inoculated leaves showed symptoms similar to those of field diseases, whereas control leaves remained healthy. The fungus with morphological-molecular features identical to the original isolate was reisolated from the disease lesions. C. liriopes causes anthracnose on Bletilla ochracea, Eria coronaria, Hemerocallis fulva, Pleione bulbocodioides (Jayawardena et al 2016) and Liriope sp. (Yang et al 2020; Chen et al 2019) in China. This is the first report of C. liriopes causing anthracnose on O. jaburan in China. Anthracnose could greatly affect ornamental value of O. jaburan, and this work can alert gardeners to prevent and control of the disease.

Manglietia decidua, named 'Hua manglietia', belonging to the Magnoliaceae family, is one of the most important ornamental plant in China. In 2019 and 2020, an unknown disease caused 3- to 12-month plants of M. decidua to wither and die in the field in Zhanjiang, Guangdong province（N21°9'3";E110°17'47"）. Initially, the infected plants showed leaves dehydration, chlorosis and wilting with water-soaked lesions on stems at ground level. About 7 days later, the plants completely wilted, collapsed and died. Delayed and stunted growth with wilting of foliage continued through the whole year. Dense white mycelial mat and small white-to-brown spherical sclerotia were observed on the surface of the stalk lesion when weather conditions were warm and humid. Approximately 10% of plants were infected. Especially from July to October 2020, up to 30% of about 500 plants were infected and died. To identify the causal agents of the disease, infected tissue and sclerotia were collected, surface disinfected in 75% alcohol for 30s and 30% hydrogen peroxide solution for 5 min, and washed with sterile water for 1 min. The surface disinfected tissue and sclerotia were put on potato dextrose agar containing ampicillin (50mg/L) and kept in an incubator at 25°C in the dark. Fast growing fungus colonies with white mycelium and numerous sclerotia developed in the plates after 6 to 8 days of incubation. The hyphae were septate, hyaline and formed typically clamp connection after 10 days of growth. Sclerotia were initially white and became tan to dark brown over time and 1.0 to 3.0 mm (2.13 mm on average, n=124) in diameter at maturity. For molecular identification，the ITS region was amplified using primer pair ITS1/ITS4 (White et al. 1990). A 666 bp PCR product was sequenced (GenBank accession no. MW093622) and shared above 99% sequence identity with some Athelia rolfsii isolates (GenBank accession Nos. HQ895869, KX499470 and AB075290). Based on morphological and molecular characteristics, the fungus was identified as Sclerotium rolfsii (teleomorph A. rolfsii) （Paul et al. 2017，Xu et al. 2010. Pathogenicity tests were conducted by inoculating ten healthy 1-year-old M. decidua plants grown in pots. Five sclerotia and mycelial mat obtained from 15-day-old cultures were buried adjacent to the stem of each unwounded healthy plant. Non-inoculated plants served as controls. After inoculation, the plants were maintained in a 25-28 ℃ greenhouse and watered regularly to keep the soil moisture content at about 15%. Symptoms of southern blight were observed on all inoculated plants, which began to wilt 7 to 10 days after inoculation and died within 15 to 20 days. The control plants remained healthy. S. rolfsii was again isolated from the artificially inoculated plants, but not from non-inoculated plants. The pathogenicity test was repeated twice and the results were the same. S. rolfsii has an extensive host range worldwide and the common host ornamental plants are Iris, Chrysanthemum, CymbidiumTrifolium, Jasminum, Begonia, and Stevia etc. in China. To our knowledge, this is the first report of southern blight caused by S. rolfsiii on M. decidua in China. M. decidua is a horticultural plant which belongs to the protected and endangered tree species. This finding is important to alert growers to realize the proper management of this disease during species protection and cultivar extension.

Manglietia decidua (Magnoliaceae) was a class I endangered plant in China. During 2018-2020, a severe root rot (about 10% - 90% disease incidence ) was observed on 2-year-old seedlings in the nursery in Yichun, Jiangxi province (N27°52'20"; E114°27'46"). Symptoms started on leaves showing dehydration and chlorosis, the root of diseased plant became black and rotted, and in severe cases, the plants withered and died. The symptomatic root tissues were cut and dipped in a 3% hydrogen peroxide solution for 5 mins, rinsed thrice with sterile water, and then placed on potato glucose agar medium containing ampicillin (50mg/L). The plates were kept in an incubator at 25-28°C for 2-3 days in the dark. The Calonectria-like fungus was consistently isolated from 100% of tissues and the colonies were feathery, moderate white aerial mycelium, surface pale brown, reverse with white outer margin, and brown inner region. The perithecia produced on carnation leaf agar were solitary, subglobose to ovoid, dark red-brown, and measured 273.8 - 427.2 × 362.6 - 628.9 µm (av. 360.9 × 429.9 µm) (n = 31). Clavate asci contained eight spores and tapered into a long thin stalk. Ascospores were hyaline, guttulate, straight to slightly curved with rounded ends, 36.8- 66.1×4.4-7.3 μm (av. 49.9 × 5.9 μm) (n = 52), 1-septate, constricted at the septum and aggregated in the upper third of the ascus. On PDA，conidia formed on penicillate conidiophores within 10 days were hyaline, 1(-3)-septate, cylindrical, rounded at both ends, straight, 36.5-61.7 × 5.0-7.2 μm (av. 50.7 × 6.2 µm) (n=48). Isolate HML 20 and 27 were used to further confirm species identity by five loci analysis：ITS (MZ389092 and MZ389093), ACT (MZ398252 and MZ398253), HIS3 (MZ398254 and MZ398255), TEF1-α (MZ398256 and MZ398257), and TUB2 (MZ398258 and MZ398259). NCBI BLASTN showed the high sequence identity with Calonectria ilicicola ex-type culture CBS 190.50 (CMW 30998) (Liu et al 2020): 100 % for ITS (MT359727), TUB2 (AY725631), and HIS3 (MT335506), 99.22% for ACT (MT335036), 99.80% for TEF1-α (MT412797). Maximum likelihood (ML) analysis and Bayesian inference (BI) based on the combined ITS, tub2, his3 and tef1 sequence using RAxML v.1.0.0 and MrBayes v. 3.2.1 software revealed that isolate HML 20 and 27 clustered together with C. ilicicola strains in C. kyotensis species complex. Thus, the fungus was identified as C. ilicicola (anamorph: Cylindrocladium parasiticum) based on morpho-molecular criteria (Lombard et al. 2010). Pathogenicity was determined under greenhouse conditions (25-30 ℃). The 2-year-old plants grown in 25-cm pots for 20 days were inoculated. Five 6-mm mycelial plugs from 7-day culture on PDA were buried 5 cm under the soil adjacent to the unwounded taproot of each plant and the plants were watered regularly to keep the soil moisture content at about 15%. After ten days, inoculated plants began to show chlorosis symptoms on leaves and collapsed within 15 to 20 days, while no symptoms were observed on control plants. The same colonial fungus was successfully reisolated. Calonectria ilicicola is an economically important plant pathogen worldwide, which causes diseases on Arachis hypogaea, Cinnamomum kanahirai, Glycine max, Medicago sativa, Sassafras randaiense, and Vaccinium spp. etc. in China (Gai et al 2017, Fei et al 2018, Zhang et al 2020 ). As far as we know, it is first report of C. ilicicola causing root rot on M. decidua. At present, this disease is an important threat to the conservation of M. decidua.

Papaya (Carica papaya L.) is a tropical fruit consumed worldwide due to its nutritional, medicinal and pharmacological properties. In China, papaya was widely planted in Guangdong, Guangxi, Hainan, Yunnan, Fujian and Taiwan provinces. From September to December in 2015-2020, fruit with internal black rot disease was observed in papaya plantation in Xuwen, Guangdong province (N20°20'9"; E110°14'45"), approximately 5% fruits on about 85% trees were infected every year. The infected fruits showed the symptom of 'false-ripening' and the pericarp color changed from green to yellow earlier than that of normal fruits. In the cavity of diseased fruits, the sarcocarp black rotted and conspicuous mycelia were observed. Mycelia and infected tissues from symptomatic fruits were picked up, placed on potato dextrose agar (PDA) with 50mg/L ampicillin and incubated at 25± 2 ℃ in the dark. The fungus was purified by spore dilution plate method. Fast-growing colonies with dense, floccose, cottony mycelium were initially white gradually becoming buff brown. Macroconidia were falcate, 3-5 septa with foot-shaped cell and 10.35-41.50 (av. 25.41±6.82) ×1.90-5.95 (av. 3.67±0.85) µm (n>140) in size after 7 days of incubation on carnation leaf agar (CLA). There were scarce microconidia. Chlamydospores were intercalary, solitary or in chains, globose or irregular, hyaline to light brown. The morphological characteristics of the fungus were similar to that of Fusarium sulawesiense (Maryani et al. 2019). The internal transcribed spacer region (ITS) (KU881904 and KY436233), translation elongation factor 1-alpha (tef1) (KU894408 and KY436232), and RNA polymerase second largest subunit (rpb2) (KU894409 and KY436231) were sequenced from two isolates to cofirm species identification. Blast analysis in the FUSARIUM-ID and the NCBI databases revealed above 99 to 100% identity match with the F. sulawesiense strains NRRL34056, NRRL34059, NRRL34004 and NRRL43730 (Xia et al 2019). Maximum likelihood (ML) analysis and Bayesian inference (BI) based on the concatenated sequences using RAxML v.1.0.0 and MrBayes v. 3.2.1 software revealed that the isolates were resolved in the same clade with the F. sulawesiense strains. Thus, the fungus was identified as F. sulawesiense based on morphological characteristics and molecular criteria. To confirm pathogenicity, five healthy fruits were injected with 200 μl of spore suspension (approximately 104 spores/ml) in the field and laboratory, and isovolumetric sterile water served as control. Each fruit was sealed with a plastic bag and kept at natural temperature (about 25-30 ℃). All the inoculated fruits developed typical symptoms after 30 days in the field and 15 days in the laboratory, whereas no symptoms were observed on the control fruits. F. sulawesiense was reisolated from inoculated fruits, but not from non-inoculated fruits. F. sulawesiense displayed a broad host which included Oryza sativa, Musa nana, Citrus reticulata, and Colocasia esculenta etc. in China (Wang et al. 2019). To our knowledge, this is the first report of F. sulawesiense causing internal black rot on papaya fruit. This work is important for papaya growers to prevent this disease in time.

Leaf spot disease on the spider lily [Hymenocallis littoralis (Jacq.) Salisb.] continues to cause serious problems in China. To confirm the pathogen, the pathogenicity of isolates from diseased leaves was tested according to Koch’s postulates. The isolates were tentatively identified using morphological characteristics and confirmation was done by phylogenetic analysis of the translation elongation factor 1-alpha gene (TEF1), the actin gene (ACT), and internal transcibed spacer (ITS) sequences using neighbor-joining (NJ), maximum parsimony (MP), and Bayesian inference (BI) methods. The pathogen was identified as Phyllosticta hostae. Molecular analysis indicated very little diversity in the TEF1, ACT, and ITS gene. This is the first report of P. hostae causing leaf spot disease on spider lily in China.

In July 2013, an unknown fruit internal brown rot disease was observed on white-fleshed pitahaya (Hylocereus undatus) in Zhanjiang, Guangdong province, China. Based on morphological characteristics and phylogenetic analysis of ITS sequences, the pathogen was determined as Neoscytalidium dimidiatum.