Development and validation of a real-time PCR assay for detection and quantification of Tuber magnatum in soil

• Published in: BMC microbiology Vol. 12; no. 1; p. 93
• Main Authors: Iotti, Mirco, Leonardi, Marco, Oddis, Marilena, Salerni, Elena, Baraldi, Elena, Zambonelli, Alessandra
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 06-06-2012; BioMed Central; BMC
• Subjects: Ascomycota - genetics; Ascomycota - isolation & purification; Colony Count, Microbial - methods; Deoxyribonucleic acid; DNA; DNA Primers - genetics; DNA, Fungal - genetics; DNA, Ribosomal Spacer - genetics; Genetic aspects; Italy; ITS primers; Methodology; Microbiology; Oligonucleotide Probes - genetics; Physiological aspects; Polymerase chain reaction; Real time; Real-time PCR; Real-Time Polymerase Chain Reaction - methods; Soil DNA extraction; Soil Microbiology; Studies; Taq-man probe; Truffle production; Truffles; Tuber magnatum; Tuber magnatum DNA concentration; Italy
• ISSN: 1471-2180; 1471-2180
• DOI: 10.1186/1471-2180-12-93

Tuber magnatum, the Italian white truffle, is the most sought-after edible ectomycorrhizal mushroom. Previous studies report the difficulties of detecting its mycorrhizas and the widespread presence of its mycelium in natural production areas, suggesting that the soil mycelium could be a good indicator to evaluate its presence in the soil. In this study a specific real-time PCR assay using TaqMan chemistry was developed to detect and quantify T. magnatum in soil. This technique was then applied to four natural T. magnatum truffières located in different regions of Italy to validate the method under different environmental conditions.
The primer/probe sets for the detection and quantification of T. magnatum were selected from the ITS rDNA regions. Their specificity was tested in silico and using qualitative PCR on DNA extracted from 25 different fungal species. The T. magnatum DNA concentration was different in the four experimental truffières and higher in the productive plots. T. magnatum mycelium was however also detected in most of the non-productive plots. Ascoma production during the three years of the study was correlated with the concentration of T. magnatum DNA.
Taken together, these results suggest that the specific real-time PCR assay perfected in this study could be an useful tool to evaluate the presence and dynamics of this precious truffle in natural and cultivated truffières.