Morphology, phylogeny, and pathogenicity of Trichothecium, Alternaria, and Fusarium species associated with panicle rot on Chenopodium quinoa in Shanxi Province, China

Abstract

Quinoa panicle rot (QPR) is a novel disease that poses a significant threat to quinoa production in China. Typical symptoms on panicles include a film of pale pink, grey‐white, or dark brown mould on the grains during the grain‐filling stage. Furthermore, QPR causes quinoa grain discolouration, unfilling, and malformation. In total, 37 isolates were identified as belonging to three species: Trichothecium roseum (nine isolates), Alternaria alternata (12), and Fusarium citri (16) based on morphology, and phylogenetic and pathogenicity characterization. The present study shows for the first time that T. roseum, A. alternata, and F. citri are the pathogens responsible for QPR. An evaluation of the growth and germination rates revealed a significant difference among the three species, with T. roseum and F. citri isolates having higher fitness in warmer (25–30℃) and humid conditions (water activity ≥0.98). However, A. alternata preferred cooler (20–25℃) and more arid conditions, and germinated in a wide range of water activities (water activity of 0.90–1.00). Among the three species, T. roseum and F. citri are probably responsible for the pink and grey diseased grains in humid regions, and A. alternata for the black‐brown diseased grains in arid regions. Pathogenicity tests showed that all three species could infect the quinoa panicles. The results of this study provide a basis for the recognition and management of QPR.

Characterization and toxicological potential of Alternaria alternata associated with post-harvest fruit rot of Prunus avium in China

“…The effect of water activity (a w ) on fungal mycelium was examined using the method described by Yin et al (2022) with slight modifications. The a w of the PDA medium was maintained at 0.99, 0.98, 0.97, 0.96, 0.95, 0.94, 0.92, and 0.91 by adding different amounts (v/v) of glycerol (HOCH 2 CHOHCH 2 OH) (Xilong Scientific Co., Ltd. Guangdong, China), and a w was checked three times at 6-h intervals by a Water Activity Meter (AQUA-LAB Dew point a w meter 4TE, PYNN160703) before inoculation.…”

Marketed Quinoa (Chenopodium quinoa Willd.) Seeds: A Mycotoxin-Free Matrix Contaminated by Mycotoxigenic Fungi

“…and BenA and CaM ( Aspergillus spp.). For each genus, the sequences of the isolates obtained in the present investigation, as well as those of representative isolates obtained from Genbank, including those of the main Alternaria ( Table S3 ), Penicillium ( Table S4 ), Aspergillus ( Table S5 ), Cladosporium ( Table S6 ) and Fusarium ( Table S7 ) species reported in the literature on C. quinoa ( Table S8 ) [ 18 , 19 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ], were used. Moreover, Stemphylium herbarum CBS 191.86 [ 31 ], Talaromyces flavus CBS 310.38 [ 30 ], Cercospora beticola CBS 116,456 [ 56 ] and Neurospora crassa OR74A [ 57 ] were included as outgroups for phylogenetic analysis of Alternaria , Aspergillus and Penicillium , Cladosporium and Fusarium , respectively.…”

Characterization, phylogeny and pathogenicity of Fusarium solani causing quinoa basal stem rot in Shanxi Province, China

“…Unfortunately, new and emerging quinoa diseases were discovered in new cultivation environments (Colque‐Little et al, 2021). In the last 5 years, seven new quinoa diseases caused by viruses (Sun et al, 2021), oomycetes (Yin et al, 2018) and fungi (Brahmanage et al, 2020; Sun et al, 2018; Yin et al, 2019, 2020, 2022) have been reported in different provinces of China.…”

“…incarnatum‐equiseti species complex) in Italy (Beccari et al, 2021), and quinoa panicle rot (caused by F . citri ) in China (Yin et al, 2022). Notably, there has been no detailed research on the species of pathogens associated with Fusarium wilt (Danielsen et al, 2003).…”

“…in Peru (Danielsen et al, 2003), damping-off (caused by F. avenaceum and Fusarium spp.) in the Czech Republic (Dřímalková & Veverka, 2004) and Japan (Isobe et al, 2019), browning or necrotic symptoms on seeds (caused by the F. incarnatum-equiseti species complex) in Italy (Beccari et al, 2021), and quinoa panicle rot (caused by F. citri) in China (Yin et al, 2022). Notably, there has been no detailed research on the species of pathogens associated with Fusarium wilt (Danielsen et al, 2003).…”