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Fungal endophytes of spotted knapweed: taxonomical, geographical and chronological analysis
A le x e y S h ip u n o v , Anil Kumar Raghavendra, G e o rg e N e w c o m b e

D e p a r tm e n t o f F o r e s t R e s o u r c e s , C e n te r fo r R e s e a r c h o f In v a s iv e S p e c ie s a n d S m a ll P o p u la tio n s ( C R IS S P ) , U n iv e r s ity o f Id a h o



Hypotheses of invasion and distribution of endophytes
· Enhanced Mutualism Hypothesis ­ new endophytes obtained in the invaded range (IR) from native hosts ("host-jumping") · Enemy Release Hypothesis ­ enemies are left behind in the native range (NR) ­ some endophytes are cryptic pathogens · Novel Weapons Hypothesis ­ co-introduced NR endophytes produce chemical compounds ("co-introduction")


Life cycle of knapweed endophytes (hypothesis)


Sampling

· · · · ·

61 knapweed populations sampled, plus 10 populations of native North American plants (Saussurea americana, Cirsium brevifolium, Festuca idahoensis etc.) 5 plants and 100 achenes per sample Endophytes isolated from achenes ­ 2291 isolates Isolates grouped in 288 morphological groups (strains) Each group has been sequenced (ITS and "Alt a 1"), 102 haplotypes obtained


Accumulation curves
T h e y a r e n o t a s y m p to tic : · T h e m o s t fr e q u e n t h a p lo ty p e s s h o u ld b e a n a ly z e d ; · F o r o r d in a tio n s , o c c u r r e n c e ( in s te a d o f a b u n d a n c e ) is m o re u s e fu l; · F o r s im ila r itie s b e tw e e n c o m m u n itie s is b e tte r to u s e a c c u m u la tio n - b a s e d in d e x e s (lik e C h a o in d e x )


BLAST identity and new species
Possible new species

# o f h a p lo ty p e s


Taxonomic and phylogenetic structure


The case of putative co-introduction: Phoma tracheiphila
The endophyte pho250 (South Germany) has 99% identity with GenBank sequences of Phoma tracheiphila, very dangerous pathogen of Citrus trees


Comparison of diversity between two ranges

Invaded range (N. America)

Native range (Europe)


Endemic and cosmopolitan haplotypes


Distribution of Botrytis 017/095 and Cladosporium 063


Ordination of communities
Principal coordinates analysis (PCO) based on Chao similarity indexes East U.S.

Cirsium brevifolium

Northern Idaho


Fungal haplotypes that characterize communities
Species are common for NR

Species are common for IR


Phylogenetic ordination via Phylocom (Web et al., 2007)
m e a n p h y lo g e n e tic d is ta n c e s b a s e d o n IT S M P p h y lo g e n e tic tr e e

Fescue (Festuca spp.) communities

Aster jessicae and Cirsium brevifolium communities


Repeated sampling

Some of most widespread fungi are repeatedly isolated whereas some Alternaria species are not easy to re-isolate


Diversity and climate

We have higher isolation frequencies from sites where late summer and fall (AugustNovember) precipitation is higher


Acknowledgements
·Timothy Prather · Cort Anderson · Rebecca Ganley · Sanford Eigenbrode · Hongjian Ding · Maryse Crawford · The team of R project for statistical computing · Idaho State Government Web-site of the project: http://uidaho.edu/~shipunov