Identification of Trichothecium roseum and determination of carbon and nitrogen sources utilization ability

Abstract:

[Objective] To provide a theoretical basis for the diagnosis and integrated control for the common bean pathogen. [Methods] This paper exploited the methods of conventional separation and Koch’s postulates to isolate and determine the pathogen of beans. Explicited it’s taxonomic status by combining morphological characteristics with ITS sequence analysis, and determined the ability of the pathogen to use carbon and nitrogen sources. [Results] The results showed that this pathogen mainly damaged pods, it would form round or nearly round brown, sunken spots on the pods surface, the pink mildew layer would appear on the lesion surface later; the conidium was obpyriform, single spore, hyaline, there was a diaphragm in the middle of the mature spores, the size was (6.23?12.42) μm×(12.07?24.67) μm. The rDNA-ITS sequence of the pathogenic fungus shared similarity was more than 99% with Trichothecium roseum (KC816070) that had reported. So, the pathogen was identified as Trichothecium roseum combined the morphologic characteristics with ITS sequence analysis. The grew rate of colony of Trichothecium roseum was fastest at the culture of maltose medium, and the growth on the medium of various carbon sources were faster than the control significantly (P<0.05); In the different nitrogen media, L-leucine could promote the growth of colony, but L-arginine and Urea had the significant inhabiting effects (P<0.05). [Conclusion] The results of this study had some reference value for the other plant diseases caused by Trichothecium roseum.