Puccinia caricis-artemisiae Jing X. Ji, Zhuang Li, Y. Li & Kakish., 2022

Ji, Jingxin, Li, Zhuang, Li, Yu & Kakishima, Makoto, 2022, Phylogenetic approach for identification and life cycles of Puccinia (Pucciniaceae) species on Carex (Cyperaceae) from northeastern China, Phytotaxa 542 (3), pp. 221-255 : 240-242

C9: Puccinia caricis-artemisiae Jing X. Ji, Zhuang Li, Y. Li & Kakish. sp. nov. ( Fig. 12 )

MycoBank No: MB 838299.

Diagnosis:— This species is characterized by the smallest teliospores among species having spermogonial and aecial stages on Artemisia .

Typus:— CHINA, Jilin Province, West of Changbai Mountain, telia on Carex neurocarpa Maxim. , 2 September 2018, M. Kakishima & J. X. Ji, HMJAU 8874 , Holotype . CHINA, Jilin Province, Jilin City, Jiaohe , spermogonia and aecia on Artemisia sp. , 1 July 2018, M. Kakishima & J. X. Ji, HMJAU 8883 , Epitype .

Etymology: —Named after host plant genera associated with different stages.

Description: — Spermogonia amphigenous, honey-yellow, subepidermal, flask-shaped, obscure, type 4 of Cummins & Hiratsuka (2003). Aecia is mostly hypophyllous, cupulate with peridia, Aecidium - type. Peridial cells firmly conjunct, cubic to polygonal, hyaline. Aeciospores catenulate, globose to subglobose, angular, 15.0–18.0 × 13.5–16.5 µm (av. 16.5 × 15. 0 µm); walls hyaline, 0.5–0.9 µm (av. = 0.7 µm) thick, densely verrucose with big granules. Uredinia hypophyllous, scattered, minute, brown to dark brown, covered by epidermis but eventually erumpent. Urediniospores globose, subglobose or obovoid, 20.0–26.0 × 14.5–19.0 µm (av. 22.0 × 17.0 µm); walls brown, echinulate, 1.1–1.6 µm (av. 1.3 µm), germ pores 3, equatorial. Telia hypophyllous, blackish brown, rounded to broadly elliptic, erumpent. Teliospores broadly clavate, ellipsoid, mostly conical at apices, constricted at the septum, attenuate at the base, 40.0–51.0 × 16.0–20.0 µm (av. 47.0 × 17.5 µm); walls brown, 0.7–1.4 µm (av. 1.0 µm) thick at sides, 7.1–12.6 µm (av. 9.9 µm) at apices; pedicels persistent, hyaline, 22.5–57.0 µm (av. 37.0 µm) long.

Additional specimens examined from northeastern CHINA: — Jilin Province, West of Changbai Mountain , uredinia and telia on Carex neurocarpa , 1 September 2018, HMJAU 8878 , 8886 . Jilin Province, Baishan , uredinia, and telia on C. neurocarpa , 3 September 2018, HMJAU 8875 . Jilin Province, Jilin, uredinia, and telia on C. neurocarpa , 4 September 2018, HMJAU 8876 . Jilin Province, Changchun , uredinia, and telia on C. neurocarpa , 31 August 2018, HMJAU 8880 , 1 October 2018, HMJAU 8881 . Jilin Province, Yanji , uredinia, and telia on C. neurocarpa , 23 September 2014, HMJAU 8882 . Jilin Province, South of Changbai Mountain , uredinia and telia on C. neurocarpa , 2 September 2018, HMJAU 8884 . Jilin Province, Tumen , uredinia and telia on C. neurocarpa , 28 June 2019, HMJAU 8885 . Heilongjiang Province, Wuchang , uredinia and telia on C. neurocarpa , 2 July 2018, HMJAU 8877 , 9 September 2017, HMJAU 8879 . Jilin Province, South of Changbai Mountain , uredinia and telia on Carex sp. , 2 September 2018, HMJAU 8934 .

Hosts and distribution in northeastern CHINA ( Fig. 1 ): —Spermogonia and aecia on Artemisia sp. (Asteraceae) (B). Uredinia and telia on Carex neurocarpa (A, B, C, D, F); Carex sp. (D).

Note: —Four species, P. atrofusa (Dudl. &Thom.) Holw. , P. caricis-macrocephalae Dietel , P. caricis-stipatae Y. Harada and P. dioicae var. micropuncta Y. Ono , have been reported as heteroecious species alternating between Artemisia and Carex ( Ono 1983, Harada 1986, Hiratsuka et al. 1992, Zhuang et al. 1998, Azbukina 2005, 2015). However, morphological characteristics of the specimens in this clade are different from these species, especially in the shape and size of teliospores and the number of urediniospore germ pores. The specimens are phylogenetically close to P. caricis-stipatae and P. dioicae var. micropuncta , but have a distinct linage from these species ( Fig. 3 ) and are, therefore, described as a new species. This species has the smallest teliospores (40.0–51.0 × 16.0–20.0 µm) compared to the other four taxa ( P. atrofusa : 38–63 × 15–23 µm, P. caricis-macrocephalae : 48–90 × 18–27 µm, P. caricisstipatae : 48–65 × 15–21 µm, P. dioicae var. micropuncta : 35–60 × 13–22 µm). This species has three urediniospore germ pores, while other species have two or four germ pores. Many species having spermogonial and aecial stages on genera of Asteraceae were treated as P. dioicae Magnus or P. extensicola Plowr. ( Arthur 1934, Hylander et al. 1953, Wilson & Henderson 1966), however, reconsideration of these taxonomic treatments is required. This species is widely distributed in the area studied, although spermogonial and aecial stages are only found in one location.

Figures

FIGURE 1. Collection areas in northeastern China. A. Changchun area in Jilin Province. B. Jilin area in Jilin Province. C. Mountanious area in southern Heilongjiang Province. D. Area around Changbai Mountains in Jilin Province. E. Baicheng area in western Jilin Province. F. Yanbian area in eastern Jilin Province. G. Tonghua area in southeastern Jilin Province.

FIGURE 3. Phylogenetic tree of specimens on Cyperaceae and related host plants constructed by MP method based on ITS+28S regions of rDNA. Bootstrap values of MP and ML are followed by the Bayesian posterior probabilities (Bpp) on the nodes in the topology.Asterisk (*) represents bootstrap values or Bpp less than 50% in the topology. Sample data are shown with voucher specimen number or GenBank accession number, and host plant. Sequence data determined in this study are shown in color. Teliospore shapes are shown in each clade detected, and new species are shown by asterisk (*) on clades. 0, I: Spermogonial and aecial host genus. Asterisk (*) on host plants: Spermogonial and aecial host plants.

FIGURE 12. Puccinia caricis-artemisiae on Artemisia sp. (A–F) and Carex neurocarpa (G–K). A. Plants producing spermogonia and aecia on the leaf surface in the field. B. Aecia on the lower leaf surface. C. Vertical section of an aecium surrounded with peridia. D. Aeciospores. E. An aecium observed under SEM. F. An aeciospore with granules on the surface observed under SEM. G, H. Uredinia and telia on the lower leaf surface. I. Urediniospores. J. Vertical section of an uredinium. K. Vertical section of a telium. Scale bars: C = 50 μm, D, I = 20 μm, E = 10 μm, F = 5 μm, J, K = 30 μm.