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bioRxiv · 10.1101/481382

A novel polyphasic identification system for genus Trichoderma

Dou, K.·Lu, Z.·Wu, Q.·Ni, M.·Yu, C.·Wang, M.·Li, Y.·Wang, X.·Xie, H.·Chen, J.
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Abstract

As the rapid-changing in Trichoderma taxonomy, an efficient identification of Trichoderma species is an urgent issue for Trichoderma-based research. In this study, based on the current taxonomy of Trichoderma, we constructed curated databases including 338 ITS sequences, 435 TEF1 sequences, 415 RPB2 sequences and 28 phenotypic characters. In addition, a polyphasic identification system (PIST) was developed. Within PIST, the resolution ability of molecular and phenotype characters could be combined for species identification in a step-by-step way. Compared with other identification systems, the involved Trichoderma species were extended from 88 to 252 species and 175 from 188 tested Trichoderma species could be identified within PIST. In most tested cases, three nucleotide markers and phenotypic characters showed improved identification performance. The TEF1 sequences have superior resolution than other characters.\n\nImportanceThe genus Trichoderma is important to human society with a wide application in industry, agriculture and environment bio-remediation. Thus, a quick and accurate identification of Trichoderma spp. is paramount since it is usually the first step to conduct a Trichoderma-based scientific research and is an obstruction especially for those researchers as nematologist, chemists, nutritionist and the like, lacking of taxonomic knowledge of fungi.

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Dou, K., Lu, Z., Wu, Q., Ni, M., Yu, C., Wang, M., Li, Y., Wang, X., Xie, H., Chen, J.. 2018-11-29. A novel polyphasic identification system for genus Trichoderma. https://doi.org/10.1101/481382

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