Alternaria vignae C. X. Huang & J. X. Deng, 2022

Huang, Cheng Xin, Liu, Feng Yin, Gou, Ya Nan, Deng, Jian Xin & Li, Mei Jia, 2022, Alternaria vignae sp. nov. (Ascomycota: Pleosporaceae) from Vigna unguiculata in China, Phytotaxa 556 (3), pp. 281-290 : 286-287

Alternaria vignae C. X. Huang & J. X. Deng sp. nov. Fig. 2b–j

MycoBank: 843124

Type— China, the Inner Mongolia Autonomous Region, Hohhot City , the farm of Inner Mongolia Agricultural University, from leaves of Vigna unguiculata , 20 Aug, 2017, J. X. Deng, YZU-H-009 (holotype), ex-type culture YZU 171714 .

Etymology:—In reference to the host genus name, Vigna unguiculata

Descriptions:— Colony on PDA, light yellow in the center, white at the edge, hyphae flocculent, sulfur yellow to pure yellow in reverse, 39-47 mm in diam. after 7 days at 25 °C in darkness ( Fig. 2b ). Conidiophores smooth, straight or curved, 42-130 × 4-6 μm in size, with 2-9 transverse septa. Conidiogenous cells clavate, slightly enlarged at apex, 6-19 × 4-6 μm, sometimes branched to produce another conidium ( Fig. 2 e-f). Conidia usually solitary or in a chain with two units ( Fig. 2 c-d). On V8A, beakless conidia long elliptical body, with a size range of 46-67 × 13-17 μm, 5-8 transverse septa and 1-2 longitudinal septa; short blunted beak (16-94 × 2-4 μm) conidia obclavate and narrow-to broad-ellipsoid, with a size range of 45-76 × 12-20 μm, 5-8 transverse septa and 1-2 longitudinal septa; long filiform beak (100-150 × 2-3 μm) conidia with, a size range of 53-63 × 15-18 μm, 6-8 transverse septa and 1-3 longitudinal septa ( Fig. 2 j-l). On PCA, beakless conidia, 43-94 × 15-31 μm in size, with 4-8 transverse septa and 0-4 longitudinal septa; short blunted beak (13-96 × 2-4 μm) conidia, 50-75 × 14-32 μm in size, with 5-8 transverse septa and 0-5 longitudinal septa; long filiform beak (114-324 × 2-4 μm) conidia, 49-83 × 15-30 μm in size, with 5-9 transverse septa and 1-5 longitudinal septa ( Fig. 2 g-i).

Materials examined:— China, the Inner Mongolia Autonomous Region, Hohhot City , the farm of Inner Mongolia Agricultural University , from leaves of Vigna unguiculata , 20 Aug , 2017, J. X. Deng, YZU-H-009 (holotype), ex-type culture YZU 171714 , living cultures YZU 171715 .

Notes:—Morphologically, it is quite similar to A. helianthiinficiens based on conidial morphology ( Table 2 ). The new species produces shorter filiform beak than A. helianthiinficiens on V8A. Except that, there are few conidial evidences to indicate that it is a new species. However, Alternaria vignae can be readily separated with A. helianthiinficiens based on the multigene sequence analyses of ITS, GAPDH, RPB2 and TEF1.

Figures

FIGURE 2. Alternaria vignae (YZU 171714, ex-type). a: samples; b: colony on PDA for 7 days at 25 ˚C; c–d: sporulation patterns on PCA; e–f: conidiophores; g–i: conidia on PCA; j–l: conidia on V8A. Scale bars: c-l=25 μm.