Pecan, Carya illinoinensis, is an economically im- portant nut producing tree that can establish ectomycorrhizal symbiosis with a high diversity of fungi. In the southern USA, truffles (Tuber spp.) sometimes fruit prolifically in cultivated pecan orchards and regularly associate with pecan roots as ectomycorrhizae (ECMs). It has been demonstrated that some valuable European truffle species (e.g., Tuber borchii and Tuber aestivum) can form ECMs with pecan seedlings in nursery con- ditions. Thus, pecan may represent an attractive alternative host to forest trees for truffle growers given the potential for co- cropping truffles and pecans. To further explore the capacity of pecan to host truffle symbionts, pecan seedlings were inoculated with species of black truffles that are economically important in Europe, T. melanosporum and T. brumale. Ectomycorrhizae were characterized molecularly and their morphology was de- scribed in detail. Mycorrhization rates on pecan roots were assessed over a 2-year period. Tuber melanosporum and T. brumale produced well-formed ECMs with a level of root colonization in the first year of 37.3 and 34.5%, respectively. After 24 months, the level of mycorrhization increased for T. brumale (49.4%) and decreased for T. melanosporum (10.5%) inversely to that of non-target ECM greenhouse contaminants (e.g., Sphaerosporella brunnea, Trichophaea woolhopeia, Pulvinula constellatio). To as- sess whether mating types segregated in T. melanosporum as been reported for other host species, we amplified the mating-type locus from single T. melanosporum ECM be- longing to different seedlings over a 2-year period. The two mating idiomorphs were nearly equally represented along the 2-year time span: MAT 1-1-1 decreased from 59.4% in the first year to 48.5% in the second year after inoculation. Data re- ported in this study add to knowledge on the mycorrhization of pecan trees with commercial truffles and has application to truffle and nut co-cropping systems.
Mycorrhization of pecan (Carya illinoinensis) with black truffles: Tuber melanosporum and Tuber brumale
MAROZZI, GIORGIOWriting – Original Draft Preparation
;ALBERTINI, EmidioSupervision
;DONNINI, DomiziaSupervision
2017
Abstract
Pecan, Carya illinoinensis, is an economically im- portant nut producing tree that can establish ectomycorrhizal symbiosis with a high diversity of fungi. In the southern USA, truffles (Tuber spp.) sometimes fruit prolifically in cultivated pecan orchards and regularly associate with pecan roots as ectomycorrhizae (ECMs). It has been demonstrated that some valuable European truffle species (e.g., Tuber borchii and Tuber aestivum) can form ECMs with pecan seedlings in nursery con- ditions. Thus, pecan may represent an attractive alternative host to forest trees for truffle growers given the potential for co- cropping truffles and pecans. To further explore the capacity of pecan to host truffle symbionts, pecan seedlings were inoculated with species of black truffles that are economically important in Europe, T. melanosporum and T. brumale. Ectomycorrhizae were characterized molecularly and their morphology was de- scribed in detail. Mycorrhization rates on pecan roots were assessed over a 2-year period. Tuber melanosporum and T. brumale produced well-formed ECMs with a level of root colonization in the first year of 37.3 and 34.5%, respectively. After 24 months, the level of mycorrhization increased for T. brumale (49.4%) and decreased for T. melanosporum (10.5%) inversely to that of non-target ECM greenhouse contaminants (e.g., Sphaerosporella brunnea, Trichophaea woolhopeia, Pulvinula constellatio). To as- sess whether mating types segregated in T. melanosporum as been reported for other host species, we amplified the mating-type locus from single T. melanosporum ECM be- longing to different seedlings over a 2-year period. The two mating idiomorphs were nearly equally represented along the 2-year time span: MAT 1-1-1 decreased from 59.4% in the first year to 48.5% in the second year after inoculation. Data re- ported in this study add to knowledge on the mycorrhization of pecan trees with commercial truffles and has application to truffle and nut co-cropping systems.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
