Lasiodiplodia syzygii C.R. Meng, Qian Zhang & Yong Wang bis, 2021

Meng, Chao-Rong, Zhang, Qian, Yang, Zai-Fu, Geng, Kun, Zeng, Xiang-Yu, Thilini Chethana, K. W. & Wang, Yong, 2021, Lasiodiplodia syzygii sp. nov. (Botryosphaeriaceae) causing post-harvest water-soaked brown lesions on Syzygium samarangense in Chiang Rai, Thailand, Biodiversity Data Journal 9, pp. 60604-60604 : 60604

Lasiodiplodia syzygii C.R. Meng, Qian Zhang & Yong Wang bis sp. nov.

Materials

Type status: Holotype. Occurrence: catalogNumber: HGUP 9719 ; recordedBy: Wang Yong; Taxon: scientificName: Lasiodiplodiasyzygii; kingdom: Fungi; class: Dothideomycetes; order: Botryosphaeriales; family: Botryosphaeriaceae; genus: Lasiodiplodia; Location: country: Thailand; stateProvince: Chiang Rai; Identification: identifiedBy: Chao-Rong Meng; dateIdentified: 2020; Record Level: type: ex-type living culture GUCC 9719.1; MFLU 19-0565, isotype, isotype living culture MFLUCC 19-0257. Type status: Other material. Occurrence: catalogNumber: HGUP 9720 and HGUP 9721 ; recordedBy: Wang Yong; Taxon: scientificName: Lasiodiplodiasyzygii; kingdom: Fungi; class: Dothideomycetes; order: Botryosphaeriales; family: Botryosphaeriaceae; genus: Lasiodiplodia; Location: country: China; stateProvince: Guiyang; Identification: identifiedBy: Chao-Rong Meng; dateIdentified: 2020; Record Level: type: living cultures GUCC 9719.2, GUCC 9719.3 and GUCC 9719.4

Description

Pathogenic on Syzygium samarangense . Sexual morph: Undetermined. Asexual morph (Fig. 2 ): Conidiomata up to 2 mm diam., pycnidial, covered with hyphae, black, globose, ostiolate, solitary, separate, uniloculate, immersed to semi-immersed. Conidiomatal wall composed of thick-walled, dark brown cells of textura angularis, becoming thin-walled and hyaline towards the inner region. Paraphyses cylindrical, aseptate, hyaline. Conidiophores reduced to conidiogenous cells. Conidiogenous cells 10-14.5 × 3.5-4.5 μm (average = 11 × 3.7 μm, n = 20), hyaline, smooth, holoblastic forming conidia at their tips. Conidia thick-walled, Conidiomatal wall up to 1 μm wide, ovoid with both ends rounded, hyaline and remaining so for a long time, becoming pale brown with obsolete striations and occasionally with 1-septate after discharging from the conidioma, (27-)30-32(-36) × (13-)15-17(-20) μm (average = 31.3 × 16.4 μm, n = 50), L/W = 1.9.

Culture characteristics: Conidia germinate on PDA within 24 hours at room temperature (25-30°C) with germ tubes produced from both ends of the conidia. Colonies with white fluffy mycelium on PDA, after 7 days become olivaceous-grey at the centre, white at the edge, raised, fluffy, dense filamentous.

Notes

Lasiodiplodia syzygii strains are closely related to L. rubropurpurea , but formed a distinct, well-supported clade in the phylogenetic analyses. Base-pairs comparisons between L. syzygii ex-type strain (GUCC 9719.1) and ex-type strain of L. rubropurpurea (WAC 12535) found seven base differences (1.3%) in ITS region and five differences (0.6%) on LSU, but nine differences (2.1%) in tub2 and 34 in TEF1-a (10.4%) (Table 2 ). Lasiodiplodia syzygii produced larger pycnidia (up to 2 mm) and larger conidiogenous cells (10-14.5 × 3.5-4.5 μm) than L. rubropurpurea (0.5-1.5 mm and 7-13 × 3-5 μm) ( Burgess et al. 2006).

Etymology

In reference to the host from which the fungus was first isolated.

Figures

Figure 2. Lasiodiplodia syzygii (MFLUCC 19 - 0257). a. infected fruit; b, c. Conidiomata on the host; d. Section through a conidioma; e. Conidia developing amongst paraphyses; f-h. Conidia formed on conidiogenous cells; i-m. Immature conidia; n-o. Colonies on PDA culture; n. From above; o. From below. Scale bars: b = 300 μm, c = 140 μm, d = 50 μm, e = 20 μm, f-m = 10 μm.