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Abstract Truffle growers devote great efforts to improve black truffle productivity, developing agronomic practices such as ‘truffle nests’ (peat amendments that are supplemented with truffle spore inoculum). It has been hypothesized that improved fruiting associated with nests is linked to stimulation of truffle mycelia previously established in soil or to changes generated in soil fungal community. To assess this, we used real-time PCR to quantify black truffle extraradical mycelium during 2 years after nests installation. We also characterized the fungal community via high-throughput amplicon sequencing of the ITS region of rRNA genes. We found that neither the abundance of truffle mycelium in nests nor in the soil—nest interphase was higher than in the bulk soil, which indicates that nests do not improve mycelial growth. The fungal community in nests showed lower richness and Shannon index and was compositionally different from that of soil, which suggests that nests may act as an open niche for fungal colonization that facilitates truffle fruiting. The ectomycorrhizal fungal community showed lower richness in nests. However, no negative relationships between amount of truffle mycelium and reads of other ectomycorrhizal fungi were found, thus countering the hypothesis that ectomycorrhizal competition plays a role in the nest effect.
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Optimising in vitro culture conditions for the truffle Tuber brumale
The vegetative propagation of ectomycorrhizal truffle fungi is limited by their slow mycelial growth. Many factors including media, isolate genotypes and environmental conditions can alter fungal mycelial growth rates. This study aimed to improve the in vitro growth rate of Tuber brumale by determining the optimal carbohydrate and nitrogen sources, temperature and pH. After 8 weeks, the highest level of growth and densest hyphal branching were recorded in the medium containing glucose as the main carbohydrate. For nitrogen, glutamine (200 mg N l-1) provided the greatest hyphal growth and density compared to the other amino acid treatments. Regarding temperature, 16?C proved to be optimal for T. brumale growth and branching. Media of pH 6 and pH 7 were most favourable for the growth of T. brumale. The results from this research provide baseline data on the vegetative nutrition of T. brumale and have implications for the in vitro culture of winter truffle hyphae.
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- Award ID(s):
- 1946445
- PAR ID:
- 10486751
- Publisher / Repository:
- Botanica Serbica
- Date Published:
- Journal Name:
- Botanica Serbica
- Volume:
- 47
- Issue:
- 2
- ISSN:
- 1821-2158
- Page Range / eLocation ID:
- 259 to 269
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.2298/BOTSERB2302259S
