Diaporthe melongenicola Fallahi, Jayawar. & K. D. Hyde, 2025

Diaporthe melongenicola Fallahi, Jayawar. & K. D. Hyde sp. nov.

Fig. 20 View Figure 20

Etymology.

‘ melongenicola ’ refers to the host plant species from which the fungus was isolated.

Description.

Pathogenic to makhuea ( Solanum melongena ) and causes blight, stem cankers, and fruit rot. Sexual morph not observed. Conidiomata pycnidial, superficial to embedded, solitary to aggregated, with single or multiple cavities, globose, with cream conidial mass, up to 200 μm in diameter. Conidiophores hyaline, smooth, straight, unbranched, rounded at the tip, and wider at the base, septate, 9–20 × 1.2–2.9 μm (mean = 13.4 × 1.9 μm, n = 15). Paraphyses intermingled among conidiophores, hyaline, smooth, septate, 9–33 × 1.4–1.5 μm (mean = 24 × 1.16 μm, n = 15). Beta conidia filiform, curved at one tip, hyaline, aseptate, rounded at tips, 15–27 × 1–2 μm (mean = 20 × 1.5 μm, n = 30). Alpha and gamma conidia are absent.

Culture characteristics.

Colonies on PDA reach 70–80 mm in diameter after seven days of growth at 25 ° C in the dark, fluffy and slightly felted with age, circular in shape, with cottony growth of the aerial mycelium in rings, grey to olivaceous grey, pale brown with age. The reverse is reddish brown, with many black dots.

Material examined.

Thailand • Chiang Rai, Mueang Chiang Rai District, Doi Hang , stem canker in makhuea ( Solanum melongena ), January 2023, Maryam Fallahi, dried culture MF 90-2 ( MFLU 24-0244 , holotype), ex-holotype culture, MFLUCC 24-0242 .

Notes.

In the phylogenetic tree generated in this study, strain MFLUCC 24-0242 formed a distinct branch within the D. sojae species complex in the subclade that includes the type strains of D. morindendophytica ( ZHKUCC 22-0069 , holotype) and D. tectonendophytica ( MFLUCC 13-0471 , ex-type) with 89 % ML bootstrap support and 0.90 BYPP (Fig. 16 View Figure 16 ) and is introduced here as a new species, namely Diaporthe melongenicola . The base pair differences between Diaporthe melongenicola ( MFLUCC 24-0242 ) with type strains of closely related species are presented in Table 4 View Table 4 . A pairwise homoplasy index (PHI) test indicated no significant recombination (Φw = 1.0) between D. melongenicola ( MFLUCC 24-0242 , holotype) and its closely related taxa (Fig. 19 View Figure 19 ). These species are different from our isolate by producing alpha conidia and diverse culture characteristics. Considering both morphology and molecular data, D. melongenicola ( MFLUCC 24-0242 ) could be identified as a novel species on makhuea ( Solanum melongena ) in northern Thailand.