First Report of <i>Chaetomium globosum</i> Causing Leaf Spot Disease on <i>Zanthoxylum bungeanum</i> in China

Zanthoxylum bungeanum Maxim. is a perennial plant of the family Rutaceae.This crop is extensively grown in China for its great economic worth as seasoning and medicine, as well as its significant ecological worth in prevention and control of rocky desertification.A leaf spot disease infecting Z. bungeanum was found in July 2023 at Zhenfeng City (2544921.380N,10556947.150E;1,083 m), Guizhou Province, China, with an incidence rate of approximately 25%.The symptoms manifested as brown, circular or nearly circular spots that later enlarged and turned dark brown or black in the center.Symptomatic leaves were gathered and cut into small pieces (about 5 5 mm) for use in isolating and identifying the causal agent, surface disinfected with 2% sodium hypochlorite for 90 s and 75% alcohol for 30 s, rinsed three times in sterile ddH 2 O, plated on potato dextrose agar (PDA), and incubated at 28C.Fifteen fungal isolates with the same colony features were obtained.The colonies on PDA grew slowly, attaining 82 to 90 mm in diameter in 15 days, and were initially white but changed to pale grayish yellow with age.Perithecia were lemon green and 6.5 to 8.5 10.0 to 14.0 m (average = 7.5 12.0 m, n = 30).Ascospores were lemon-shaped, slightly pointed at the ends, grayish brown, and 9.5 to 12.0 8.0 to 9.0 m (average = 11.0 8.5 m, n = 30).These features were consistent with Chaetomium globosum Kunze (Wang et al. 2016).In addition, the primers ITS5/ITS4 (White et al. 1990), LROR/LR5 (Vilgalys and Hester 1990), and Bt2a/Bt2b (Glass and Donaldson 1995) were used to amplify and sequence the internal transcribed spacer (ITS) region, large subunit (LSU), and b-tubulin (tub2) genes by PCR, respectively.The ITS,