Unraveling the Life Cycle of Nyssopsora cedrelae: A Study of Rust Diseases on Aralia elata and Toona sinensis
1
Department of Biological Science, Kunsan National University, Gunsan 54150, Republic of Korea
2
Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
3
Department of Forestry, Environment and Systems, Kookmin University, Seoul 02707, Republic of Korea
4
Division of Environmental Science and Ecological Engineering, College of Life Sciences and Biotechnology, Korea University, Seoul 02841, Republic of Korea
5
Center for Convergent Agrobioengineering, Kunsan National University, Gunsan 54150, Republic of Korea
*
Author to whom correspondence should be addressed.
J. Fungi 2024, 10(4), 239; https://doi.org/10.3390/jof10040239
Submission received: 22 December 2023
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Revised: 15 March 2024
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Accepted: 18 March 2024
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Published: 22 March 2024
(This article belongs to the Special Issue Fungal Plant Pathogens)
Abstract
:Rust disease poses a major threat to global agriculture and forestry. It is caused by types of Pucciniales, which often require alternate hosts for their life cycles. Nyssopsora cedrelae was previously identified as a rust pathogen on Toona sinensis in East and Southeast Asia. Although this species had been reported to be autoecious, completing its life cycle solely on T. sinensis, we hypothesized that it has a heteroecious life cycle, requiring an alternate host, since the spermogonial and aecial stages on Aralia elata, a plant native to East Asia, are frequently observed around the same area where N. cedrelae causes rust disease on T. sinensis. Upon collecting rust samples from both A. elata and T. sinensis, we confirmed that the rust species from both tree species exhibited matching internal transcribed spacer (ITS), large subunit (LSU) rDNA, and cytochrome oxidase subunit III (CO3) mtDNA sequences. Through cross-inoculations, we verified that aeciospores from A. elata produced a uredinial stage on T. sinensis. This study is the first report to clarify A. elata as an alternate host for N. cedrelae, thus providing initial evidence that the Nyssopsora species exhibits a heteroecious life cycle.
1. Introduction
Rust disease, caused by members of the order Pucciniales, poses a severe threat to diverse trees and crops [1,2]. This group often demonstrates a complex life cycle, which frequently involves switching between primary and alternate host plants. This heteroecious characteristic plays a central role in the epidemiology of rust diseases [3,4], requiring a comprehensive understanding of all host plants involved.
Toona sinensis (syn. Cedrela sinensis; Meliaceae), also known as the red toon or Chinese mahogany, is a tall deciduous tree that grows up to 20 m in height. This tree is native to East and Southeast Asia and is usually grown to produce high-quality timber, which is ideal for crafting furniture and musical instruments because of its sophisticated reddish colour and durability. In East Asia, its young leaves are utilized as a vegetable as well as for treating several ailments in traditional medicine [5,6].
Aralia elata (Araliaceae), also known as the Korean angelica tree, is a woody plant widely distributed throughout East Asia. This plant is often grown as an ornamental tree because of its unique characteristics, including spiny stems, toothed leaves, and clusters of small white flowers bearing black drupes as fruits. This tree is utilized as a traditional medicinal plant for its pharmacological effects, such as its anti-tumour, anti-inflammatory, and hepatoprotective effects [7]. In Korea, its young shoots are harvested in the spring and used in various Korean dishes because of their pleasant aroma and soft texture [8]. As of 2021, its production had reached 1383 tons, estimated to be worth 20 billion KRW [9].
Nyssopsora cedrelae is known as a rust pathogen that affects Ailanthus altissima, Toona serrata (=Cedrela serrata), and T. sinensis (=C. sinensis) [10], produces uredinial and telial stages, and has been reported in China, Japan, and Korea [11,12,13]. However, its life cycle is not fully understood. Through inoculation experiments using basidiospores obtained from teliospores, Kakishima et al. initially reported that this rust species could complete its life cycle on a single host [14], producing aecia (uredinoid aecia), uredinia, and telia entirely on T. sinensis. However, its aecial stage is not distinctly recognized in nature due to the morphological similarities between the aecial and uredinial stages, and no spermogonium has been found [11]. Consequently, the life cycle of N. cedrelae remains unclear.
Rust disease of A. elata is widespread throughout Korea. While the spermogonial and aecial stages of this rust have been observed on A. elata, the other stages of its life cycle remain elusive, leading to the conjecture that this rust may be heteroecious, utilizing different host plants for developing the other life stages. To date, two rust species, Nyssopsora asiatica and Puccinia caricis-araliae (also known as Aecidium araliae), have been reported on A. elata [11,12,15]. However, the morphologies and life cycles of these species are quite different. N. asiatica is a microcyclic autoecious species forming only telia on Acanthopanax sciadophylloides, Aralia chinensis, A. cordata, A. elata, A. spinosa, Evodiopanax innovans, Kalopanax innovans, and Merrilliopanax listeri [10,11]. The spermogonial and aecial stages that occur on A. elata in Korea are similar to those that occur on P. caricis-araliae in their symptoms but differ in morphology, and these stages are frequently observed in areas where N. cedrelae occurs on T. sinensis. Therefore, we suspected that these stages on A. elata are in fact the spermogonial and aecial stages of N. cedrelae.
This study is the first to report A. elata as an alternate host for N. cedrelae, thus providing initial evidence that the Nyssopsora species exhibits a heteroecious life cycle. In the present study, we comprehensively characterized rust disease samples on A. elata and T. sinensis through morphological and molecular phylogenetic analyses as well as cross-inoculation tests. We aimed to identify the causal agent of rust disease on A. elata in Korea and to clarify the relationships of its spermogonial and aecial stages on A. elata with the uredinial and telial stages of N. cedrelae on T. sinensis.
2. Materials and Methods
2.1. Sample Collection
Thirty-three rust samples from Aralia elata and Toona sinensis were collected across various locations in Korea. Rust-infected leaves were prepared as dried specimens and preserved at the Kunsan National University (KSNUH) and Korea University (KUS-F) for further processing. In addition, three Japanese specimens of N. cedrelae were provided by the herbarium of the Department of Botany, National Museum of Nature and Science, Tsukuba, Japan (TNS-F), for comparison with the Korean samples. All herbarium specimens used for molecular phylogenetic and morphological analyses in this study are summarized in Table 1.
2.2. DNA Extraction, Amplification, Sequencing and Phylogenetic Analysis
Genomic DNA was extracted from rust-infected samples using a MagListo 5M Plant Genomic DNA Extraction Kit (Bioneer, Daejeon, Republic of Korea), following the manufacturer’s instructions. Polymerase chain reaction (PCR) was performed to amplify the internal transcribed spacer (ITS) rDNA region with primers ITS5u [16] and ITS4rust [17], large subunit (LSU) regions with primers LRust1R and LRust3 [16], and the cytochrome oxidase subunit III (CO3) mtDNA region with primers CO3-F1 and CO3-R1 [16]. The PCR products were purified using an AccuPrep® PCR/Gel Purification Kit (Bioneer, Daejeon, Republic of Korea) and sequenced by the Macrogen sequencing service (Macrogen, Seoul, Republic of Korea). The resulting sequences were edited using DNASTAR software 7.1 (Lasergen, Madison, WI, USA).
The ITS, LSU, and CO3 sequences were compared to those of the closest related species in the GenBank database using the Basic Local Alignment Search Tool (BLASTn). The sequences of each marker were aligned using the FFT-NS-2 algorithm method in MAFFT version 7 [18]. Phylogenetic trees were constructed using the minimum evolution and maximum likelihood methods based on the Tamura–Nei model in MEGA 7 [19]. Statistical support for the branches of the phylogenetic trees was evaluated by the bootstrap method with 1000 replicates. Reference sequences from GenBank used in the phylogenetic analysis are listed in Table 2.
2.3. Morphological Analysis
The symptoms and macrostructures of rust-infected specimens were observed under a stereomicroscope (M205C; Leica, Wetzlar, Germany). The micromorphological characteristics were examined and photographed using a differential interference contrast (DIC) light microscope (Axio Imager 2; Carl Zeiss, Oberkochen, Germany). At least 50 rust sori and spores were measured per sample, and their measurements are represented as follows: (minimum–) standard deviation towards the minimum—standard deviation towards the maximum (–maximum) (mean). Scanning electron microscopy (SEM) (S-4800+EDS; Hitachi, Tokyo, Japan) was used for detailed morphological analysis.
2.4. Cross-Inoculation Experiments
Cross-inoculation experiments were conducted to demonstrate the pathogenicity of aeciospores from A. elata on T. sinensis. Aeciospores from rust-infected leaves of A. elata (KSNUH1831) were harvested using a spore collector (Tallgrass Solutions Inc., Manhattan, NY, USA) and stored in a refrigerator at 4 °C for an hour. Three healthy T. sinensis plants were inoculated by spraying a suspension of aeciospores in sterile water (1.1 × 106) onto their leaves. Inoculated plants were then kept in a humid chamber at room temperature (25 °C) for three weeks and monitored for rust-symptom development. Two non-inoculated plants served as controls.
3. Results
3.1. Phylogeny
The ITS and LSU rDNA sequences of rust samples collected from A. elata and T. sinensis were identical. Among the 33 rust samples, slight sequence differences were observed at two sites in the ITS region and one site in the LSU region. BLASTn searches revealed that the Korean and Japanese samples were closest to Nyssopsora altissima from Ailanthus altissima in China. However, there were 17 nucleotide differences from N. altissima in the ITS sequences and a gap in the LSU sequences. In the phylogenetic trees of the concatenated alignment of ITS and LSU sequences (Figure 1), samples from both host plants were consistently grouped with the maximum bootstrapping support value, indicating the robustness of this phylogenetic grouping. The phylogenetic trees revealed two distinct clades within the Nyssopsora species based on their host plants. A clade that includes N. cedrelae shares the same host plants, A. elata and T. sinensis, whereas members of the other clade, including N. echinata (type species of Nyssopsora), originated from various host plants.
The CO3 sequences, spanning 649 bp, exhibited no sequence differences across all rust samples. In the phylogenetic tree of the CO3 sequences (Figure 2), samples from both host plants formed a distinct clade that had the highest level of bootstrapping support. Moreover, this clade was distinctly segregated from the Gymnosporangiaceae, Pucciniaceae, and Sphaerophragmiaceae families, further underscoring the unique phylogenetic position of our samples.
3.2. Morphology
The symptoms of the Korean rust specimens on A. elata appeared as chlorotic spots, forming spermatogonia and aecia (Figure 3A–F). The infected leaves and stems became deformed (Figure 3C), and as the disease progressed, they increasingly withered (Figure 3D). The spermogonia were epiphyllous, scattered, subepidermal, yellow, and conical-shaped (type 5 of Cummins and Hiratsuka [2]), and measured 100–200 μm in diameter (Figure 3G). The aecia were hypophyllous or cauligenous, yellow to orange, cupulate with peridia, and measured 450–1250 μm (av. 770 μm) in diameter (Figure 3E,F,J). Peridial cells were rectangular, rhomboid, and measured (16.5–)19.6–23.0(–25.7) × (10.4–)12.7–16.6(–20.5) μm (av. 21.36 × 14.78 μm), with a thick verrucose wall (Figure 3H). Aeciospores were globose to subglobose, pale yellow, and measured (14.1–)14.4–16.5(–18.9) × (11.9–)12.5–14.6(–17.0) μm (av. 15.45 × 13.61 μm), with a verrucose, thin wall containing 1–2 large granules (Figure 3I,K,L).
Rust symptoms on T. sinensis appeared as chlorotic spots on the upper leaf surface, forming uredinia and telia on the lower leaf surface (Figure 4A–F). During the uredinial stage, infected leaves exhibited light green chlorotic spots on the upper surfaces (Figure 4C). As the disease progressed to the telial stage, the leaves dried progressively and shed prematurely (Figure 4E). Uredinia on the T. sinensis collected in Korea were amphigenous, mostly hypophyllous, erumpent, scattered or aggregated, yellow to orange, round, and measured 200–589 μm (av. 354 μm) in diameter (Figure 4D,G,K). Urediniospores were mostly subglobose, rarely obovoid, yellowish, and measured (15.4–)16.6–19.1(–21.4) × (12.2–)14.9–17.2(–18.8) μm (av. 17.88 × 16.06), with an echinulate wall 1.5–3.0 μm in thickness (Figure 4H,L; Table 2). Telia were amphigenous, mostly hypophyllous, erumpent, scattered or aggregated, dark brown to black, pulverulent, and measured 500–2400 μm (av. 1123 μm) in diameter (Figure 4F,I,M). Teliospores were 3-celled, subglobose-trigonal, dark brown, with a hyaline pedicel on each spore, and measured (28.2–)30.2–33.6(–35.6) × (28.6–)30.4–34.9(–36.8) (av. 31.61 × 32.71 μm) (Figure 4J). The walls were smooth, 1.0–2.5 μm thick, light brown, with 13–21 projections on each spore, bi- or tri-branched tips, and measured 3.0–9.5 μm (Figure 4N).
3.3. Pathogenicity
When healthy T. sinensis leaves were inoculated with aeciospores from A. elata (Figure 5A,B as a control), chlorotic spots began to appear on the leaf surfaces two weeks after inoculation (Figure 5C). The symptoms were similar to those observed in the natural environment. After three weeks, all inoculated plants exhibited more pronounced rust symptoms and formed yellow uredinia on their leaf surfaces (Figure 5D–G), from which echinulate urediniospores were produced (Figure 5H), matching the morphological features of N. cedrelae. After five weeks, three of these plants persisted in the uredinial stage without progressing to the telial stage in the experiment.
4. Discussion
In the present study, we uncovered the life cycle of the rust pathogen N. cedrelae. Morphologically, the rust samples on Aralia elata, an essential woody plant in Korean cuisine, were somewhat similar to the characteristics of those from Puccinia caricis-araliae [15], another rust species found on A. elata. They had unique large granules, but the aeciospores were smaller than those of P. caricis-araliae (15.45 × 13.61 μm in Nyssopsora cedrelae versus 21.0 × 18.5 μm in P. caricis-araliae). Further, the type of spermogonia differed between the Korean samples and P. caricis-araliae (type 5 versus type 4). The characteristics of the projections on the teliospore walls of the T. sinensis samples corresponded well with those of N. cedrelae rather than of other Nyssopsora species, even though the teliospores from the present Korean and Japanese samples were smaller than those previously described (Table 3). The features of urediniospores closely matched those of N. cedrelae. Our phylogenetic study supported the notion that N. cedrelae is a rust pathogen affecting Aralia elata in Korea as well as Toona sinensis in Japan and Korea. Although our samples were morphologically similar to Nyssopsora altissima which has been described from Ailanthus altissima in China [20], they exhibited many sequence differences in the ITS regions.
As rust diseases pose a significant risk to forestry and agricultural productivity due to their severe impact on crop yield and quality [22,23], understanding their life cycles, especially their alternate hosts, can potentially enhance disease management strategies [3,4]. Our study revealed that N. cedrelae, a rust pathogen associated with T. sinensis, has an alternate host, namely, A. elata. The molecular phylogenetic identity found in the rust species affecting A. elata and T. sinensis provides substantial evidence linking the rust diseases on the two trees. The results of the inoculation test demonstrated that A. elata is a spermogonial and aecial host (alternate host) of N. cedrelae, thereby confirming the heteroecious life cycle of this rust pathogen. Kakishima et al. reported its autoecious life cycle, producing aecia (uredinoid aecia), uredinia, and telia, with basidiospore inoculations obtained from teliospores [14]. However, this result may be due to inoculum contamination with urediniospores during basidiospore inoculations because spermogonia were not reported in the inoculations, and uredinoid aecia were produced after basidiospore inoculations. These uredinoid aecia are suspected to present as uredinia after infection with urediniospores. Our results resolve the long-standing enigma that is the life cycle of N. cedrelae, contributing to a better understanding of the epidemiology and dispersion of this pathogen.
Globally, thirteen Nyssopsora species have been reported on various woody plants, including Anacardiaceae, Apiaceae, Araliaceae, and Meliaceae [2,11,24,25,26]. To date, their aecial stage has not been observed, leading to the speculation that they exhibit an autoecious life cycle, either microcyclic (producing only the telial stage) or hemicyclic (producing the uredial and telial stages). Our results indicate the potential presence of alternate hosts in the life cycle of the genus Nyssopsora and provide compelling evidence that supports the hypothesis of Henderson [27] that some Nyssopsora species, including N. cedrelae and N. koelreuteriae, might exhibit a heteroecious life cycle by producing an aecial stage on Apiaceae or Araliaceae. This finding represents not only the first observation of the spermogonial and aecial stages but also the first report of host-alternating in the family Nyssopsoraceae. Our results highlight the benefits of integrating traditional cross-inoculation testing with advanced molecular methods for studying rust pathogens and their complex life cycles.
5. Conclusions
This study represents a substantial advancement in our understanding of the dynamics of rust diseases affecting two economically valuable trees, A. elata and T. sinensis. We revealed the widespread presence of N. cedrelae on A. elata and elucidated its heteroecious life cycle, alternating between A. elata and T. sinensis. This finding emphasizes the potential threat that N. cedrelae poses to the cultivation and economic value of these two species. The insights gained from the current research are crucial for developing efficient approaches for managing rust diseases on these trees.
Author Contributions
Conceptualization, H.-D.S. and Y.-J.C.; Formal analysis, J.S.L., M.K., J.-H.P. and H.-D.S.; Funding acquisition, and Y.-J.C.; Investigation, J.S.L., M.K., J.-H.P. and H.-D.S.; Methodology, J.S.L.; Project administration, Y.-J.C.; Resources, M.K. and H.-D.S.; Software, J.S.L.; Supervision, Y.-J.C.; Validation, J.S.L., M.K. and J.-H.P.; Visualization, J.S.L.; Writing—original draft, J.S.L. and Y.-J.C.; Writing—review and editing, J.S.L., M.K., J.-H.P., H.-D.S. and Y.-J.C. All authors have read and agreed to the published version of the manuscript.
Funding
This research was supported by the National Academy of Agricultural Science grant (PJ014956) from the Rural Development Administration, Korea.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
The data will be made available by the authors on request.
Conflicts of Interest
The authors declare no conflicts of interest.
References
- Yamaoka, Y. Recent outbreaks of rust diseases and the importance of basic biological research for controlling rusts. J. Gen. Plant Pathol. 2014, 80, 375–388. [Google Scholar] [CrossRef]
- Cummins, G.B.; Hiratsuka, Y. Illustrated Genera of Rust Fungi; American Phytopathological Society: Saint Paul, MN, USA, 2003. [Google Scholar]
- Duplessis, S.; Lorrain, C.; Petre, B.; Figueroa, M.; Dodds, P.N.; Aime, M.C. Host adaptation and virulence in heteroecious rust fungi. Annu. Rev. Phytopathol. 2021, 59, 403–422. [Google Scholar] [CrossRef] [PubMed]
- Zhao, J.; Wang, M.; Chen, X.; Kang, Z. Role of alternate hosts in epidemiology and pathogen variation of cereal rusts. Annu. Rev. Phytopathol. 2016, 54, 207–228. [Google Scholar] [CrossRef] [PubMed]
- Wang, J.; Yang, Z.; Lei, T.; Zhang, Y.; Xiao, Q.; Yu, Z.; Zhang, J.; Sun, S.; Xu, Q.; Shen, S.; et al. A likely autotetraploidization event shaped the Chinese mahogany (Toona sinensis) genome. Hortic. Plant J. 2023, 9, 306–320. [Google Scholar] [CrossRef]
- Yuk, H.J.; Lee, Y.S.; Ryu, H.W.; Kim, S.H.; Kim, D.S. Effects of Toona sinensis leaf extract and its chemical constituents on xanthine oxidase activity and serum uric acid levels in potassium oxonate-induced hyperuricemic rats. Molecules 2018, 23, 3254. [Google Scholar] [CrossRef] [PubMed]
- Xia, W.; Zhou, X.; Ma, J.; Li, T.; Zhang, X.; Li, J. A Review on a Medicinal and Edible Plant: Aralia elata (Miq.) Seem. Mini Rev. Med. Chem. 2021, 21, 2567–2583. [Google Scholar] [CrossRef] [PubMed]
- Lee, C.K.; Lee, S.H.; Choi, Y.J.; Park, M.J.; Shin, H.D. Sclerotinia rot of Aralia elata caused by Sclerotinia nivalis in Korea. Plant Patho. J. 2010, 26, 426. [Google Scholar] [CrossRef]
- Korea Forest Research. 2021 Production of Forest Products; Korea Forest Research: Seoul, Republic of Korea, 2022; p. 665. [Google Scholar]
- Lütjeharms, W.J. Vermischte Mykologische Notizen I. Blumea Suppl. 1937, 1, 142–161. [Google Scholar]
- Lohsomboon, P.; Kakishima, M.; Ono, Y. A revision of the genus Nyssopsora (Uredinales). Mycol. Res. 1990, 94, 907–922. [Google Scholar] [CrossRef]
- Farr, D.F.; Rossman, A.Y. Fungal Databases, Systematic Mycology and Microbiology Laboratory; ARS, USDA: Washington, DC, USA, 2023. Available online: http://nt.ars-grin.gov/fungaldatabases/ (accessed on 15 December 2023).
- Hiratsuka, N. Uredinales collected in Korea V. J. Plant Res. 1942, 56, 53–60. [Google Scholar] [CrossRef]
- Kakishima, M.; Sato, T.; Sato, S. Notes on two rust fungi, Pileolaria klugkistiana and Nyssopsora cedrelae. Mycoscience 1984, 25, 355–359. [Google Scholar]
- Kakishima, M.; Wang, Q. Life cycle of Aecidium araliae and its new name. Mycotaxon 2014, 128, 71–78. [Google Scholar] [CrossRef]
- Beenken, L.; Zoller, S.; Berndt, R. Rust fungi on Annonaceae II: The genus Dasyspora Berk. & M.A. Curtis. Mycologia 2012, 104, 659–681. [Google Scholar] [CrossRef] [PubMed]
- Pfunder, M.; Schürch, S. Sequence variation and geographic distribution of pseudoflower-forming rust fungi (Uromyces pisi s. lat.) on Euphorbia cyparissias. Mycol. Res. 2001, 105, 57–66. [Google Scholar] [CrossRef]
- Katoh, K.; Standley, D.M. MAFFT multiple sequence alignment software version 7: Improvements in performance and usability. Mol. Biol. Evol. 2013, 30, 772–780. [Google Scholar] [CrossRef] [PubMed]
- Kumar, S.; Stecher, G.; Tamura, K. MEGA7: Molecular evolutionary genetics analysis version 7.0 for bigger datasets. Mol. Biol. Evol. 2016, 33, 1870–1874. [Google Scholar] [CrossRef] [PubMed]
- Wu, Q.; He, M.; Liu, T.; Hu, H.; Liu, L.; Zhao, P.; Li, Q. Rust fungi on medicinal plants in Guizhou province with descriptions of three new species. J. Fungi 2023, 9, 953. [Google Scholar] [CrossRef]
- Hori, S. Notes on some Japanese Uredineae. J. Plant Res. 1892, 6, 211–217. [Google Scholar] [CrossRef]
- Helfer, S. Rust fungi and global change. New Phytol. 2014, 201, 770–780. [Google Scholar] [CrossRef]
- Lorrain, C.; Gonçalves dos Santos, K.C.; Germain, H.; Hecker, A.; Duplessis, S. Advances in understanding obligate biotrophy in rust fungi. New Phytol. 2019, 222, 1190–1206. [Google Scholar] [CrossRef]
- Yadav, S.; Singh, G.; Rajwar, S.; Verma, S.K.; Gupta, S.K.; Singh, R.; Kharwar, R.N.; Kumar, S. Nyssopsoraceae, a new family of Pucciniales to accommodate Nyssopsora spp. Curr. Res. Environ. Appl. Mycol. J. Fungal Biol. 2023, 13, 523–549. [Google Scholar]
- Nagachan, S.; Goswami, R. Nyssopsora thirumalachari—A new rust from India. Indian Phytopathol. 1985, 38, 186–187. [Google Scholar]
- Carvalho, A.; Esquivel Rios, E.; Piepenbring, M. A new species of Nyssopsora (Pucciniales) from Panama. Nova Hedwig. 2014, 99, 65–70. [Google Scholar] [CrossRef]
- Henderson, D. The rust fungus genus Nyssopsora and its host relations. Edinb. Roy. Bot. Gard. Notes 1973, 32, 217–221. [Google Scholar]
Figure 1.
Maximum likelihood trees of rust species based on a concatenated alignment of the internal transcribed spacer (ITS) and large subunit (LSU) sequences. Bootstrapping support values (minimum evolution/maximum likelihood) higher than 60% are given above or below the branches. The clade, including Nyssopsora cedrelae, is highlighted in a green box, and the rust samples sequenced in this study are shown in bold. Asterisks (*) indicate sequences of holotype.
Figure 1.
Maximum likelihood trees of rust species based on a concatenated alignment of the internal transcribed spacer (ITS) and large subunit (LSU) sequences. Bootstrapping support values (minimum evolution/maximum likelihood) higher than 60% are given above or below the branches. The clade, including Nyssopsora cedrelae, is highlighted in a green box, and the rust samples sequenced in this study are shown in bold. Asterisks (*) indicate sequences of holotype.
Figure 2.
Maximum likelihood trees of rust species based on cytochrome oxidase subunit III (CO3) rDNA sequences. Bootstrapping support values (minimum evolution/maximum likelihood) higher than 60% are given above the branches. The clade, including Nyssopsora cedrelae, is highlighted in a green box, and the rust samples sequenced in this study are shown in bold.
Figure 2.
Maximum likelihood trees of rust species based on cytochrome oxidase subunit III (CO3) rDNA sequences. Bootstrapping support values (minimum evolution/maximum likelihood) higher than 60% are given above the branches. The clade, including Nyssopsora cedrelae, is highlighted in a green box, and the rust samples sequenced in this study are shown in bold.
Figure 3.
Rust disease on Aralia elata caused by Nyssopsora cedrelae. (A,B) Infected leaves of A. elata. (C) Deformed leaf and stem caused by rust infection. (D) Withered leaves. (E) Aecia in the early stage of the disease. (F) Aecia in the later stages of disease. (G) Spermogonium. (H) Peridial cells. (I) Aeciospores. (J) Aecium. (K) Aeciospore with a granule (arrow). (L) Verrucous wall ornamentation of aeciospore.
Figure 3.
Rust disease on Aralia elata caused by Nyssopsora cedrelae. (A,B) Infected leaves of A. elata. (C) Deformed leaf and stem caused by rust infection. (D) Withered leaves. (E) Aecia in the early stage of the disease. (F) Aecia in the later stages of disease. (G) Spermogonium. (H) Peridial cells. (I) Aeciospores. (J) Aecium. (K) Aeciospore with a granule (arrow). (L) Verrucous wall ornamentation of aeciospore.
Figure 4.
Rust disease on Toona sinensis caused by Nyssopsora cedrelae. (A,B) Infected leaves of T. sinensis. (C) The chlorotic spots on the upper leaf surface in uredinial stage. (D) Uredinia on the lower leaf surface. (E) The chlorotic spots on the upper leaf surface in telial stage. (F) Telia on the lower leaf surface. (G) Uredinia. (H) Urediniospores. (I) Telia. (J) Teliospores. (K) Uredinium. (L) Urediniospore. (M) Telium. (N) Teliospore.
Figure 4.
Rust disease on Toona sinensis caused by Nyssopsora cedrelae. (A,B) Infected leaves of T. sinensis. (C) The chlorotic spots on the upper leaf surface in uredinial stage. (D) Uredinia on the lower leaf surface. (E) The chlorotic spots on the upper leaf surface in telial stage. (F) Telia on the lower leaf surface. (G) Uredinia. (H) Urediniospores. (I) Telia. (J) Teliospores. (K) Uredinium. (L) Urediniospore. (M) Telium. (N) Teliospore.
Figure 5.
Cross-inoculation test. (A) Inoculation of aeciospores from Aralia elata on Toona sinensis leaves. (B) Controls. (C) the leaves with chlorotic spots two weeks after inoculation. (D,E) the rust symptoms on the upper (D) and lower (E) surfaces of infected leaves three weeks after inoculation. (F,G) Uredinia on infected leaves by inoculation. (H) Urediniospores from emerging uredinia.
Figure 5.
Cross-inoculation test. (A) Inoculation of aeciospores from Aralia elata on Toona sinensis leaves. (B) Controls. (C) the leaves with chlorotic spots two weeks after inoculation. (D,E) the rust symptoms on the upper (D) and lower (E) surfaces of infected leaves three weeks after inoculation. (F,G) Uredinia on infected leaves by inoculation. (H) Urediniospores from emerging uredinia.
Table 1.
Rust specimens of Aralia elata and Toona sinensis used in the present study.
| Host Plant | Specimens No. * | Stage ** | Locality | Collection Date | GenBank Acc. No. | ||
|---|---|---|---|---|---|---|---|
| ITS | LSU | CO3 | |||||
| Aralia elata | KSNUH1831 | S, A | Korea, Namwon-si, Jusaeng-myeon | 4 June 2022 | OR978225 | OR964864 | PP261103 |
| KSNUH1848 | S, A | Korea, Wanju-gun, Gosan Arboretum | 25 May 2022 | OR978226 | OR964865 | PP261104 | |
| KSNUH1926 | S, A | Korea, Jeonju-si, Wansan-gu, Jungin-dong | 10 June 2022 | OR978227 | OR964866 | PP261105 | |
| KUS-F12861 | S, A | Korea, Gangneung-si, Jibyeon-dong | 8 June 1994 | — | — | — | |
| KUS-F13838 | S, A | Korea, Samcheok-si, Miro-myeon | 26 May 1997 | — | — | — | |
| KUS-F16018 | S, A | Korea, Seoul, National Insitute of Forest Science | 17 June 1999 | — | — | — | |
| KUS-F24142 | S, A | Korea, Bonghwa-gun, Chunyang-myeon, Seobyeok-ri | 14 June 2009 | — | — | — | |
| KUS-F30646 | S, A | Korea, Pyeongchang-gun, Jinbu-myeon, Songjeong-ri | 20 June 2018 | OR978216 | OR964894 | — | |
| KUS-F31045 | S, A | Korea, Yangpyeong-gun, Okcheon-myeon, Jungmisan Recreation Forest | 24 June 2019 | OR978217 | OR964895 | — | |
| KUS-F32831 | S, A | Korea, Suncheon-si, Gangcheonsan County Park | 18 May 2022 | OR978247 | OR964885 | PP261113 | |
| KUS-F32847 | S, A | Korea, Jeonju-si, Mt. Geonjisan | 22 May 2022 | OR978248 | OR964886 | PP261114 | |
| KUS-F32861 | S, A | Korea, Wanju-gun, Soyang Eco-Forest | 26 May 2022 | OR978249 | OR964887 | PP261115 | |
| KUS-F32865 | S, A | Korea, Imsil-gun, Mt. Seongsusan | 27 May 2022 | OR978250 | OR964888 | PP261116 | |
| KUS-F32875 | S, A | Korea, Jangsu-gun, Seonggwansa Temple | 30 May 2022 | OR978251 | OR964889 | PP261117 | |
| KUS-F32913 | S, A | Korea, Wanju-gun, Daea Arboretum | 3 June 2022 | OR978252 | OR964890 | PP261118 | |
| KUS-F32921 | S, A | Korea, Wanju-gun, Pyeonbaek Forest | 7 June 2022 | OR978253 | OR964891 | PP261119 | |
| KUS-F33693 | S, A | Korea, Wanju-gun, Wibong Mountain Fortress | 29 May 2023 | OR978254 | OR964892 | PP261120 | |
| KUS-F33702 | S, A | Korea, Buan-gun, Sangseo-myeon, Gaeamsa Temple | 30 May 2023 | OR978215 | OR964893 | PP261121 | |
| Toona sinensis | KSNUH0876 | U | Korea, Gunsan-si, Oksan-myeon, Oksan-ri | 16 September 2020 | OR978221 | — | PP261099 |
| KSNUH1478 | U | Korea, Chilgok-gun, Gisan-myeon, Yeong-ri | 14 July 2021 | OR978222 | OR964899 | PP261100 | |
| KSNUH1519 | U | Korea, Gunsan-si, Miryong-dong | 5 August 2021 | OR978223 | OR964863 | PP261101 | |
| KSNUH1651 | T | Korea, Yeongdong-gun, Hwanggan-myeon, Masan-ri | 16 October 2021 | OR978224 | — | PP261102 | |
| KSNUH1957 | U | Korea, Buan-gun, Sangseo-myeon, Gamgyo-ri, | 8 July 2022 | OR978228 | OR964867 | PP261106 | |
| KSNUH1981 | T | Korea, Iksan-si, Osan-myeon, Jangsin-ri | 28 September 2022 | OR978229 | — | — | |
| KUS-F17635 | T | Korea, Cheongju-si, Chungcheongbuk-do Agricultural Research and Extension Services | 24 September 2000 | OR978230 | OR964868 | — | |
| KUS-F18055 | T | Korea, Seoul, Forest Research Institute | 6 November 2000 | OR978231 | OR964869 | — | |
| KUS-F19928 | T | Korea, Jinju-si, Geumsan-myeon, Cheonggoksa Temple | 16 October 2003 | OR978232 | OR964870 | — | |
| KUS-F23179 | U | Korea, Suwon-si, Seodun-dong | 7 November 2007 | — | — | — | |
| KUS-F23191 | T | Korea, Samcheok-si, Jukseoru Pavilion | 9 November 2007 | OR978233 | OR964871 | PP261107 | |
| KUS-F23988 | T | Korea, Gimhae-si, Daedong-myeon | 21 November 2008 | OR978234 | OR964872 | PP261108 | |
| KUS-F24567 | U, T | Korea, Yangyang-gun, Hyeonbuk-myeon | 14 September 2009 | OR978235 | OR964873 | PP261109 | |
| KUS-F25499 | U | Korea, Pocheon-si, Korea National Arboretum | 18 October 2010 | — | — | — | |
| KUS-F25500 | T | Korea, Pocheon-si, Korea National Arboretum | 18 October 2010 | OR978236 | OR964874 | — | |
| KUS-F27646 | U | Korea, Milyang-si, Mt. Yongdusan | 26 September 2013 | OR978237 | OR964875 | — | |
| KUS-F29339 | U | Korea, Wando-gun, Wando Arboretum | 26 July 2016 | OR978238 | OR964876 | — | |
| KUS-F29353 | U | Korea, Iksan-si, Jeollabuk-do Agricultural Research and Extension Services | 3 August 2016 | OR978239 | OR964877 | — | |
| KUS-F29959 | U | Korea, Gimcheon-si, Mt. Geumosan | 7 September 2017 | OR978240 | OR964878 | PP261110 | |
| KUS-F30343 | T | Korea, Gimcheon-si, Geumo-dong | 7 November 2017 | OR978241 | OR964879 | — | |
| KUS-F31343 | U, T | Korea, Gimcheon-si, Yogok-dong | 21 October 2019 | OR978242 | OR964880 | — | |
| KUS-F31776 | U | Korea, Gimcheon-si, Nam-myeon, Mt. Unnamsan | 23 June 2020 | OR978243 | OR964881 | — | |
| KUS-F32487 | T | Korea, Wanju-gun, Soyang-myeon, Wibongsa, Temple | 1 October 2021 | OR978244 | OR964882 | — | |
| KUS-F32982 | U | Korea, Buan-gun, Sangseo-myeon, Gaeamsa Temple | 20 June 2022 | OR978245 | OR964883 | PP261111 | |
| KUS-F33532 | T | Korea, Gochang-gun, Haeri-myeon, Songyangsa Temple | 10 November 2022 | OR978246 | OR964884 | PP261112 | |
| TNS-F99270 | U | Japan, Chiba, Noda | 16 October 2022 | OR978218 | OR964896 | PP261097 | |
| TNS-F99271 | T | Japan, Ibaraki, Inashiki | 14 November 2022 | OR978219 | OR964897 | — | |
| TNS-F99272 | T | Japan Ibaraki, Ushiku | 20 November 2022 | OR978220 | OR964898 | PP261098 | |
* KSNUH: Kunsan National University Herbarium; KUS-F: Fungal specimens of Korea University; TNS-F: Fungal specimens of National Museum of Nature and Science. ** S = spermogonial stage; A = aecial stage; U = uredinial stage; T = telial stage.
Table 2.
List of reference sequences of Nyssopsoraceae used for phylogenetic analysis.
| Rust Species | Host Plants | Specimens * | GenBank Accession No. | ||
|---|---|---|---|---|---|
| ITS | LSU | CO3 | |||
| Austropuccinia psidii | Melaleuca leucadendra | PREM 61282 | KT590037 | KT590037 | — |
| Rhodamnia angustifolia | BRIP 57793 | — | — | KT199419 | |
| Ceratocoma jacksoniae | Daviesia sp. | BRIP 57762 | — | — | KT199405 |
| Dasyspora echinata | Xylopia aromatica | BPI 746651 | JF263462 | JF263462 | — |
| Xylopia aromatica | ZT HeRB8486 | — | — | JF263513 | |
| Desmella lygodii | Lygodium japonicum | U1226 | — | — | MG907260 |
| Gymnosporangium clavariiforme | Malus sp. | HMAS:67951 | KU288644 | — | — |
| Crataegus sp. | BRIP 59471 | — | MW049261 | MW036499 | |
| Gym. juniperi-virginianae | Juniperus virginiana | DAOM 234434 | HQ317510 | — | — |
| Juniperus sp. | MCA3585 | — | MG907217 | MG907268 | |
| Melampsora euphorbiae | No data | U-00138 | DQ911599 | — | — |
| Euphorbia macroclada | BPI 863501 | — | DQ437504 | — | |
| Euphorbia macroclada | BPI 86350 | — | — | MW036501 | |
| Nyssopsora altissima | Ailanthus altissimus | GMB0103 ** | OQ067089 | OQ067529 | — |
| N. asiatica | Eleutherococcus wilsonii | QHU2022221 | OQ911496 | OQ911495 | — |
| N. echinata | Meum athamanticum | KR0012164 | — | MW049272 | — |
| N. koelreuteriae | Koelreuteria bipinnata | BBSW-1 | KT750965 | — | — |
| N. thwaitesii | Schefflera wallichiana | AMH 9528 | KF550283 | KF550283 | — |
| Puccinia graminis | Agropyron repens | No data | AF468044 | — | — |
| Glyceria maxima | BRIP:60137 | — | KM249852 | MW036505 | |
| Puccinia malvacearum | Malva sylvestris | INU_12572-2016 | KU872011 | — | |
| Malva nicaeensis | PDD:101511 | — | KX985756 | — | |
| Malva parviflora | BRIP 57522 | — | — | KX999924 | |
| Uromyces appendiculatus | Macroptilium atropurpureum | BRIP 60929 | KU296911 | — | — |
| Phaseolus vulgaris | BRIP 60020 | — | KM249870 | KX999933 | |
* AMH: Agharkar Research Institute, India; BBSW: BeiBei Southwest University, China; BPI: U.S. National Fungus Collections, USDA-ARS, USA.; BRIP: Queensland Plant Pathology Herbarium, Australia; DAOM: Canadian National Mycological Herbarium-AAFC, Canada; GMB: Guizhou Medical University, China; HMAS: Chinese Academy of Sciences, China; INU: Inonu University, Turkey; KR: Staatliches Museum für Naturkunde Karlsruhe; MCA: Muhlenberg College, USA.; PDD: Manaaki Whenua—Landcare Research, New Zealand; PREM: Plant Protection Research Institute, Republic of South Africa; QHU: Qinghai University, China; U: Naturalis Biodiversity Center, The Netherlands; ZT: Herbarium der Eidgenössische Technische Hochschule Zürich. ** A-type specimen (holotype).
Table 3.
Morphological characteristics of Nyssopsora cedrelae on Toona sinensis.
| Reference | Country | Urediniospores | Teliospores | Specimen | ||
|---|---|---|---|---|---|---|
| Size (µm) | Size (µm) | Projections | ||||
| No. | Length (µ) | |||||
| Lohsomboon, Kakishima [11] | Japan | 14–24 × 13–21 (av. 18–16) | 29–44 × 27–44 (av. 35–34) | 13–27 | 3–9 | PUR-68828 (isotype) |
| Hori [21] | Japan | 17–21 | 35–40 | – | 7 | - a |
| Lütjeharms [10] | – | – | – | 20–30 (av. 26) | – | Nr. 44 |
| In this study | Korea | 15.4–21.4 × 12.2–18.8 (av. 17.88 × 16.06) | – | – | – | KSNUH1478 |
| Korea | – | 25.1–34.4 × 16.6–35.5 (av. 30.03 × 31.79) | 13–22 | 5.3–6.9 | KSNUH1651 | |
| Korea | 16.7–20.2 × 15.1–18.7 (av. 18.14 ×16.91) | 28.2–35.6 × 28.6–36.8 (av. 31.61 × 32.71) | 14–21 | 3.2–8.3 | KUS-F23988 | |
| Korea | – | 25.2–33.0 × 25.9–34.2 (av. 30.29 × 30.08) | 15–23 | 2.9–6.8 | KUS-F25500 | |
| Korea | 14.4–20.1 × 12.8–17.1 (av. 16.80 × 15.09) | 25.1–34.4 × 16.6–35.5 (av. 30.59 × 30.97) | 14–24 | 4.1–9.5 | KUS-F31343 | |
| Japan | 15.0–17.9 × 13.0–16.2 (av. 16.40 × 15.21) | – | – | – | TNS-F99270 | |
| Japan | – | 26.8–33.8 × 25–34.7 (av. 30.38 × 31.12) | 15–22 | 3.1–7.5 | TNS-F99271 | |
| Japan | – | 25.0–35.5 × 27–35.8 (av. 31.18 × 31.02) | 14–18 | 3.3–9.4 | TNS-F99272 | |
a The morphological characteristics were measured from a specimen collected on Cedrela sinensis (now Toona sinensis) (Botanical Garden, Tokyo, Japan, 15 October 1891, S. Hori), without a herbarium number.
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MDPI and ACS Style
Lee, J.S.; Kakishima, M.; Park, J.-H.; Shin, H.-D.; Choi, Y.-J. Unraveling the Life Cycle of Nyssopsora cedrelae: A Study of Rust Diseases on Aralia elata and Toona sinensis. J. Fungi 2024, 10, 239. https://doi.org/10.3390/jof10040239
AMA Style
Lee JS, Kakishima M, Park J-H, Shin H-D, Choi Y-J. Unraveling the Life Cycle of Nyssopsora cedrelae: A Study of Rust Diseases on Aralia elata and Toona sinensis. Journal of Fungi. 2024; 10(4):239. https://doi.org/10.3390/jof10040239
Chicago/Turabian StyleLee, Jae Sung, Makoto Kakishima, Ji-Hyun Park, Hyeon-Dong Shin, and Young-Joon Choi. 2024. "Unraveling the Life Cycle of Nyssopsora cedrelae: A Study of Rust Diseases on Aralia elata and Toona sinensis" Journal of Fungi 10, no. 4: 239. https://doi.org/10.3390/jof10040239
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