Characterization of the host range and sensitivity to fungicides of Trichothecium spp. associated with fruit rot in the field and in storage

Abstract

During 2017–2019, we observed Trichothecium spp. causing fruit rot in the field and in storage. This study was conducted to examine morphological differences of the species from different hosts, reveal the species’ potential host range, and evaluate the efficacy of five fungicides. Six strains of Trichothecium spp. isolated from nectarine, peach and walnut were selected. Although the colony morphology, mycelial growth rate and spore size differed among hosts, phylogenetic analysis based on the internal transcribed spacer and part of the 5ʹ end of the β‐tubulin gene showed that all tested strains belonged to Trichothecium roseum. For its host range, 23 kinds of fruit were examined using T. roseum strain YT‐1 as an inoculum; 10 kinds of fruit, including pear, apple, mango, Chinese chestnut, pepino melon, fig and durian, were susceptible to T. roseum, with minimum inoculation concentrations ranging from 104 to 105 spores/ml. The fungicides that most effectively inhibited the six isolates were fluazinam and fludioxonil, with EC50 values of 0.07–0.1 and 0.01–0.04 μg/ml, respectively, followed by difenoconazole (0.81–2.96 μg/ml), boscalid (5.43–13.51 μg/ml) and azoxystrobin (9.18–27.25 μg/ml). Improvement of the shelf life of nectarines held in plastic trays was explored using allyl isothiocyanate (AITC) against T. roseum YT‐1. The application of 10 μl/L AITC significantly suppressed disease symptoms. The findings provide useful information for future disease emergency management in the field and for food preservation.

Biocontrol action of Trichothecium roseum against the wheat powdery mildew fungus Blumeria graminis f. sp. tritici

“…Identification of a hyperparasite on Blumeria graminis f. sp. tritici colony T. roseum has been repeatedly reported as a fungus causing postharvest disease on a variety of fruits and vegetables (Yang et al, 2003;Kasuyama and Tanina, 2007;Dal Bello, 2008;Kwon et al, 2010;Inácio et al, 2011;Hamid et al, 2014;Lin et al, 2016;Tang et al, 2016;Xue et al, 2016;Li et al, 2022). In addition, T. roseum was shown to be a potential agent for biological control of plant fungal diseases (including soybean rust) and Pauropsylla buxtoni, a disease-causing insect (Freeman and Morrison, 1949;Huang and Kokko, 1993;Kumar and Jha, 2002;Tesfagiorgis and Laing, 2010;Batta, 2020).…”

“…mycobank.org/). T. roseum is reported as a primarily fungus causing postharvest disease that infest a variety of vegetables, fruits, and crops (Barnett and Hunter, 1972), including tomato, cucumber, orange, apple, mango, strawberry, Hami melon, peppers and maize (Yang et al, 2003;Kasuyama and Tanina, 2007;Dal Bello, 2008;Kwon et al, 2010;Inácio et al, 2011;Hamid et al, 2014;Lin et al, 2016;Xue et al, 2016;Li et al, 2022). T. roseum promotes fruit degradation after infection and then disrupts the long-term preservation of fruits and vegetables (Wei et al, 2018).…”