Twin research in fungi - Phenotype vs. genotype

Abstract

Trichoderma atroviride is a filamentous fungus used widely for biological control of major plant diseases. A strain of this species (LU132) has been developed into a commercial biocontrol agent (BCA) for use in New Zealand. Its broad spectrum of antagonistic activity is linked to a wide range of biological parameters but we have limited knowledge of what specific attributes make this strain particularly effective as a BCA. The development of a molecular marker for LU132 failed, because all known marker genes had identical sequences with T. atroviride LU140, a strain that was isolated at the same time from the same paddock but had a different phenotype to LU132. To identify the level of genetic similarity between the two strains, the whole genomes were re‐sequenced via Next Generation Sequencing with a surprising result: only 2 Single Nucleotide Polymorphisms (SNPs) could be found between the genomes of LU132 and LU140. In the present study the strains were confirmed to be two different individuals by comparing the phenotypes and confirming the SNPs. Based on those results, five genes were selected whose gene expression was studied. The results are presented here and their impact on the relationship between molecular changes and phenotypic changes in T. atroviride are discussed.