10.5061/DRYAD.2NGF1VHK9
Capador, Hernan
0000-0002-4811-7756
Swedish University of Agricultural Sciences
Samils, Berit
Swedish University of Agricultural Sciences
Kaitera, Juha
Natural Resources Institute Finland
Olson, Ake
Swedish University of Agricultural Sciences
Data from: Genetic evidence for sexual reproduction and multiple
infections of Norway spruce cones by the rust fungus Thekopsora areolata
Dryad
dataset
2020
Picea abies
aecia
Sweden
Norway
2021-05-20T00:00:00Z
2021-05-20T00:00:00Z
en
93469 bytes
4
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Rust fungi are obligate parasites of plants with complex and in many cases
poorly known life cycles which may include host alteration and up to five
spore types with haploid, diploid and dikaryotic nuclear stages. This
study supports that Thekopasora areolata, the causal agent of
cherry-spruce rust in Norway spruce, is a macrocyclic heteroecious fungus
with all five spore stages which uses two host plants Prunus padus and
Picea abies to complete its life cycle. High genotypic diversity without
population structure was found, which suggests predominantly sexual
reproduction, random mating and a high gene flow within and between the
populations in Fennoscandia. There was no evidence for an autoecious life
cycle resulting from aeciospore infection of pistillate cones that would
explain the previously reported rust epidemics without the alternate host.
However, within cones and scales identical multilocus genotypes were
repeatedly sampled which can be explained by vegetative growth of the
fertilised mycelia or repeated mating of mycelium by spermatia of the same
genotype. The high genotypic diversity within cones and haplotype
inference show that each pistillate cone is infected by several
basidiospores. This study provides genetic evidence for high gene flow,
sexual reproduction and multiple infections of Norway spruce cone by the
rust fungus T. areolata which expands the general understanding of the
biology of rust fungi.
Partially nested hierarchical sampling Location level: Picea abies cones
with aecia were collected from 7 different locations in Sweden, Norway,
and Finland. At each location 30 cones were collected, from which one
scale with aecia per cone and one aecium per scale were randomly sampled.
At tree level: a more extensive sampling was made at the seed orchard in
Ã…lbrunna (Sweden), where 100 cones with aecia were sampled from 6
different trees at a distance of ca. 20 m to 600 m from each other. From
each cone, one scale with aecia and one aecium per scale were randomly
sampled. At cone level: 10 cones with aecia were randomly sampled from two
locations in Sweden (a-1 and a-4) and split longitudinally to select 10
scales across each cone, from which 10 aecia per scale were randomly
sampled (100 aecia per cone). At scale level: 3 individual scales with
aecia from cones from two different locations in Sweden (a-1 and a-4) were
thoroughly sampled (ca. 40 aecia per scale). Single aecium genotyping DNA
was extracted from each aecium following the protocol of Capador et al.,
(2018). The samples were genotyped with 8 polymorphic microsatellites
markers; Tha9, Tha61, Tha91, Tha92, Tha96, Tha105, Tha136, and Tha137,
microsatellite amplification and scoring was performed as formerly
described (Capador et al., 2018) except for a subset of samples which were
analysed with DreamTaq (ThermoFisher) instead of PIR00 (Sigma).
The dataset is in Genalex format