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Excipular reaction in IKI after KOH pre-treatment
Raúl Tena Lahoz, 01-09-2010 23:07
Raúl Tena LahozHi to all!
I have noticed a strange reaction for me. In this species all excipular tissues became brown-purplish when adding IKI after KOH. Is there a name for that?
IKI-KOH-IKI also yields the same reaction.
When only adding IKI no reaction is seen. Still no idea of the species or even the genus. No more data for the moment...
First photo only in IKI with the 10x objetive.
Thanks in advance,
Raúl
  • message #12743
Raúl Tena Lahoz, 01-09-2010 23:08
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
Second photo: IKI after KOH with the 10x objetive.
  • message #12744
Raúl Tena Lahoz, 01-09-2010 23:09
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
Third and more: IKI after KOH with the 100x objetive
  • message #12745
Hans-Otto Baral, 01-09-2010 23:09
Hans-Otto Baral
Re:Excipular reaction in IKI after KOH pre-treatment
Hi Raul

I suggest to use Melzer here, without and then with KOH-pretreatment. It could be a dextrinoid reaction which chloralhydrate enhances.

Zotto
Raúl Tena Lahoz, 01-09-2010 23:10
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
...
  • message #12747
Raúl Tena Lahoz, 01-09-2010 23:10
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
...
  • message #12748
Hans-Otto Baral, 01-09-2010 23:12
Hans-Otto Baral
Re:Excipular reaction in IKI after KOH pre-treatment
Oh, it is more violet. Then it could be hemiamyloid. In this case you should rinse your preparation with water. Simply add a drop of water to the edge and take away the lugol from the other side. This colour reminds me of the reaction in Perrotia and Proliferodiscus, and there the violet turns bright blue after rinsing.

Zotto
Raúl Tena Lahoz, 01-09-2010 23:34
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
Thanks Zotto!
Yes I tried as you say, but surely it is no hemiamyloid. I think it must be as in Proliferodiscus. Now I remember I had seen that in Belonidium aeruginosum, but only at the hairs base. I attach a bad picture from a video where you can see how KOH stains violet while it enters in the preparation. In the case of the first species occurs the same but the reaction is seen in subhymenium and ectal excipulum. Reaction is no so evident than in Belonidium (Proliferodiscus?) aeruginosum.

Cheers,
Raúl.
  • message #12751
Raúl Tena Lahoz, 08-09-2010 22:05
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
Sorry I was confused. It is not as in Proliferodiscus (violet in contact with KOH). I have checked my photos and videos and in contact with KOH I see no violet reaction. Only when I added IKI to the KOH preparation the violet came out. I attach my summary pics and species description in a pdf file. I think it is a member of Hyaloscyphaceae, but I do not know to wich genus it belongs.
Thanks,
Raúl.
Hans-Otto Baral, 08-09-2010 23:53
Hans-Otto Baral
Re:Excipular reaction in IKI after KOH pre-treatment
Very good presentation, Raul! So you got this brown-violet reaction in IKI without KOH or only after KOH? And you are sure the violet is an IKI-reaction after KOH which disappears when adding ample KOH to the IKI?

I have so far no idea. Did you also test Melzer without KOH? If the red-brown reaction is not shown in MLZ but in IKI then this is obviously hemiamyloid.

I would have guessed a Hyphodiscus but just that reaction is unknown to me in that genus, neither in Ciliolarina.

Zotto
Raúl Tena Lahoz, 09-09-2010 10:32
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
Thanks Zotto
This brown-violet reaction appeared only adding IKI after KOH. And it disappeared when adding again KOH. And then I again added IKI and got a weak violet-brown reaction.

Water
Water+KOH --> No reaction.
Water+KOH+IKI --> Excipulum brown-violet reaction. Asci tips blue.
Water+KOH+IKI+KOH --> All dead with no colour.
Water+KOH+IKI+KOH+IKI --> Weak brown-violet reaction. Asci tips blue.

Also when adding only IKI to a new preparation I got no violet reaction (I only got the typical brown colour of IKI). When I added KOH to the IKI preparation, KOH decolorized the IKI and no colours were seen. And finally, when adding again IKI, the brown-violet came out.

Water
Water+IKI --> Brown of IKI all over. Asci tips weak blue.
Water+IKI+KOH--> All dead with no colour.
Water+IKI+KOH+Water+IKI--> Weak brown-violet reaction. Asci tips blue.

Because the first time I started adding KOH (to see how VBs in spores dissapear) I thought it could not be a hemiamyloid reaction.

I have not tested Melzer. I will try to repeat all, but I have few samples...
Hope all is clear.

Raúl.
Hans-Otto Baral, 09-09-2010 10:36
Hans-Otto Baral
Re:Excipular reaction in IKI after KOH pre-treatment
The reddish reaction of IKI without KOH is sometimes difficult to see in excipula, actually. I have no idea to enhance that or make it more clear. Maybe a comparison of IKI and MLZ (both without KOH) would help. Also MLZ after KOH might give some hints. And rinsing a KOH+IKI mount with water might change the violet to a clear blue as I know from Perrotia and Proliferodiscus.

Zotto
Raúl Tena Lahoz, 10-09-2010 18:28
Raúl Tena Lahoz
Re:Excipular reaction in IKI after KOH pre-treatment
Please take a look at the pdf file.
Thanks!
Raúl.
Hans-Otto Baral, 10-09-2010 19:45
Hans-Otto Baral
Re:Excipular reaction in IKI after KOH pre-treatment
This is very strange indeed, and it is not hemiamyloid. I never heard of an IKI-reaction which needs an alcaline pH to take place. I assume that applying acids does not give the reaction.

Zotto
Hans-Otto Baral, 14-09-2010 13:54
Hans-Otto Baral
Re:Excipular reaction in IKI after KOH pre-treatment
I finally put this species in my Ciliolarina folder, the small rough pale brwnish hairs look like that.

Zotto