Scottish Rock Garden Club Forum

Cultivation => Cultivation Problems => Topic started by: Rafa on February 01, 2007, 12:35:07 AM

Title: Iris Scorch Virus
Post by: Rafa on February 01, 2007, 12:35:07 AM
Hello,

I have an aril Iris with Scorch virus and I would like to ask you if there is any treatment to avoid this virus.

Many thanks and best wishes

Rafa
Title: Re: Iris Scorch Virus
Post by: Lesley Cox on February 01, 2007, 12:58:42 AM
I don't know this virus Rafa and can't help at all but in general, I'd say that viruses need to be avoided in the first place., before they happen. After the event is too late.
Title: Re: Iris Scorch Virus
Post by: Maggi Young on February 01, 2007, 12:09:33 PM
This may help describe Rafa's problem, I have copied this info from a handy website that others may find helpful. http://www.herbs2000.com

"Iris Scorch
The cause of scorch in irises is not known, although many horticulturists have studied the problem. Scorch is a pathological condition of bearded irises, but no one knows whether similar conditions in beardless irises are caused by the same pathogen.  Aril and arilbred irises seem to be most susceptible to scorch.
Scorch does not appear to be particularly contagious since it will occur only in scattered spots of large plantings. Scorch begins with withering of the central leaves and within a few days the leaves turn a characteristic rusty red-brown, beginning at the tip and spreading down toward the base. Soon all the leaves are affected. At the same time, the roots rot and die, but the rhizome remains firm for a while after the first signs are noticed. The roots become mushy inside, then dry and hollow. Diagnose the plant at this stage by pulling it out of the ground to inspect the rhizome and roots.
To avoid iris scorch dig up the affected plants and place them in a sunny spot on asphalt paving for a week or two and then replant.
Other iris growers have had good luck if they catch the scorch early and dig the affected plants up, then dry them for about a month until they are ready to grow new roots. If you do this, it may take them two full seasons to bloom once again. In many cases, it will make better sense to discard the diseased plants. Treating the soil with calcium nitrate has helped reduce the occurrence of a similar disease in tulips and gladioli."

It seems that this "dig up and dry" treatment may sometimes work.
In the case of any plant affected by virus,we try to quarantine the plant and then get seed from it if at all possible  and start again!

Rafa, a nice letter from you this morning, thank you very much!
Title: Re: Iris Scorch Virus
Post by: Rafa on February 01, 2007, 04:18:31 PM
Many thanks,

I think the solution is almost impossible...
Title: Re: Iris Scorch Virus
Post by: Lesley Cox on February 01, 2007, 10:22:47 PM
Thanks from me too Maggi for this information. I've not seen Iris scorch in NZ though that's not to say it's not here. The North Island has a lot of pests and diseases that we here in the south don't. As Rafa says, it's a difficult one. I guess that's the reason why we have such strict import regulations for living material. It's not just weed potential but pests, deseases and all sorts of other reasons as well.
SimplePortal 2.3.5 © 2008-2012, SimplePortal