Smuts on Lygeum spartium (natural habitat)

Hi, years ago I found dark rust fungal spore mass inside the inflorescences of Lygeum spartium (Esperanto grass). Some five years later I still see the same infection in the same population. I am curious to investigate. For the moment, I can share only macro features and will hopefully work on the micro tomorrow and try to cultivate on culture media next week.

The dark brown spores only exhibits themselves inside the single floret of the species. Apart from its presence, it also deforms the flowers making it look to have 2-4 florets but it may be that each corresponds to the two glumes, lemma and palea (infection is causing dysplasia). One member (Bjorne) suggested and sp. which is probably correct, but a further resolution to species level is desired

Thank you Stefan for your message and moving the post. I follow this fungal pathogen as much as possible.

Is Julia on this forum or I have to email her?

Thanks

Thank you,

In the meantime I had a look at the spores, and they dont seem particularly interesting although i have a curiosity. The spores are globular with a preipheral rim (thick wall?) and amorphous semi-translucent bodies which I think they are guttulae. The spherical spores had a diameter of 5.0-5.8 um (see details below). Surface smooth sometimes with some eroded portions in the wall. The images are froum spores mounted in an anti-surfactant and KOH (3%).

The curious part is that within the spores mass there were spinulose spores which I judged as doubtfully artifacts/foreign extrinsic matter, but they were definitely in the spore mass extracted from the glume pockets. They were rare (1-2 in 200 spores in one slide, 1-2 in 80 spores in another). They measure about 12um. I thought it is worth mentioning.

Spore measurements

5.28 5.28

4.98 4.72

5.64 4.44

5.24 5.11

5.53 4.68

5.05 4.72

5.02 4.87

4.57 4.42

5.99 5.31

4.76 4.55

5.11 4.79

5.02 5.02

5.19 5.19

5.47 5.10

5.68 5.15

5.99 5.39

5.62 5.09

5.00 4.77

5.19 4.47

4.17 4.05

5.78 4.95

5.57 5.04

5.16 4.90

5.41 5.29

4.97 4.73

5.52 4.94

5.25 5.13

5.13 5.02

6.26 5.55

(4.2) 5 - 5.8 (6.3) × (4.1) 4.5 - 5.3 (5.6) µm

Q = 1 - 1.2 (1.3) ; N = 29

Me = 5.3 × 4.9 µm ; Qe = 1.1

Thank you Julia, investigation solved then. 😎. I have two further questions

1. Am I right to assume that it won't kill the host plant? Infection seems to be effecting only sone florets (5-20%)

2. Is the fungus 'dormant' in the host perennially and then emerges with the inflorescence.

Thank you Julia for your time and for sharing your expertise

All the best

Stephen