leaf forms in Wendy's Gold and Virus questions

[ChrisD]

Sorry I meant to say a big thank you Rollo. I think I remain somewhat sceptical that the reason for the green colouring on the outer petals of all the inverse pocs is simply a virus infection, but is a very interesting idea and one that (as you say) woulnt be too difficult to test.

Thanks again. Chris

[johnw]

RolloP - I would like to thank you as well. This has all been very detailed, informative and thought-provoking.

I just priced Azoxystrobin here, concetration says 50% 1 lb is $1092.00 (£683.39 / €828.59 ) which does several hectares.

Heritage
Fungicide
Broad spectrum fungicide for control of plant diseases. Active Ingredient:
Azoxystrobin: methyl (E)-2-{2-[6-(2-cyano- phenoxy)pyrimidin-4-yloxy]phenyl}-3- methoxyacrylate* . . . . . . . . . . . . . . . 50%
Other Ingredients:   50%
Total:   100% Contains 0.5 lb. a.i./lb. product *IUPAC
1 pound Net Weight
Product of the U.K.

I'm no chemist nor mathematician so I have to ask how does the one above compare in concentration with the Gemuse Piltzfrei Saprol that Hans uses; its label states - 250 g/l Azoxystrobin.  Is that 25% for Saprol for the home owner and 50% for the commercial?    This might be very important as labelling says toxic to some apple varieties so one would want to make sure the mix was correct and equal to Hans' 0,1%/ litre.

johnw

[johnw]

Hans  - I meant to ask you do you spray the foliage or do a thorough soil drench with Azoxystrobin?

For stag the best time I presume is as the noses first poke through the soil.

johnw

[ronm]

I found this an interesting read,

http://www.pacificbulbsociety.org/pbslist/2011-July/3umq86gl3dk919ll1qgeajofh0.html#year=2011&month=6&id=ojbn2sc1qgvmilddhui6p0osf5

[Hans J]

Hans  - I meant to ask you do you spray the foliage or do a thorough soil drench with Azoxystrobin?

For stag the best time I presume is as the noses first poke through the soil.

johnw

John ,

I spray with Azoxystrobin all plants in pots
When I get new Galanthus so I give all the bulbs in a solution ( also 0,1 % ) for one hour inside - after this I pot the plant and drench it with Azoxystrobin

When first noses poke through the soil it it here to early  - or do you have all your snowdrops in a greenhouse ? ( minimum of 15° to use it )

[ChrisD]

RolloP - I would like to thank you as well. This has all been very detailed, informative and thought-provoking.

I just priced Azoxystrobin here, concentration says 50% 1 lb is $1092.00 (£683.39 / €828.59 ) which does several hectares.

Heritage
Fungicide
Broad spectrum fungicide for control of plant diseases. Active Ingredient:
Azoxystrobin: methyl (E)-2-{2-[6-(2-cyano- phenoxy)pyrimidin-4-yloxy]phenyl}-3- methoxyacrylate* . . . . . . . . . . . . . . . 50%
Other Ingredients:   50%
Total:   100% Contains 0.5 lb. a.i./lb. product *IUPAC
1 pound Net Weight
Product of the U.K.

I'm no chemist nor mathematician so I have to ask how does the one above compare in concentration with the Gemuse Piltzfrei Saprol that Hans uses; its label states - 250 g/l Azoxystrobin.  Is that 25% for Saprol for the home owner and 50% for the commercial?    This might be very important as labelling says toxic to some apple varieties so one would want to make sure the mix was correct and equal to Hans' 0,1%/ litre.

johnw

John - The maths is not too difficult but it is easy to get confused.

A 1% solution (of a solid) is 1g in a total volume of 100mls, so a 25% solution of Saprol is 25g in 100mls (which is obviously the same concentration as 250g/l)

The situation for Azoxystrobin is slightly more difficult. It appears that you are buying 1lb of powder of which 50% is the active ingredient so if you made a 10% solution (10g in a total volume of 100mls) you have a 5% solution of the active ingredient.

The best advice is to follow the instructions on the packaging.

Chris

[JimF]

Perfect timing!
I just bought Bonide's Infuse granular (not liquid) to use to treat some Stag I've discovered. The chemical is Triophanate-methyl (dimethly cl, 4'-0 phenylenebis [3- thioallophanate]) - (that's a brainfull) - at 2.08%.

It is specifically advertised for bulb, tuber, and corm crops and lawn turf, etc., but only gives rates per acres. I got it because research shows this chemical degrades into carbendazim, which is used by a friend in the UK to treat Stag, but is a chemical off market in the US.

I now see that I have 2.08% solution and can now do the math. Thanks.

The bag does say to test and wait for 5 days on a plant to see if it is harmed. An innocent healthy nivalis will be the lab galanthus.

Jim

[RolloP]

For those interested, please see the the recently published paper regarding "reverse bi-colour breaks in Daffodils being caused by virus". This has long been suspected by Daffodil breeders and this paper seems to confirm the suspicion. It does, a) indicate the amount of work required to confirm such a suspicion,  b) how complicated this interaction between plant and viruses can be, and c) how little is understood regarding the mechanism of virus induced colour breaks at a molecular level, work which can only be justified by a high value commercial crop. There may be parallels with "inverse poculiform" types in Snowdrops.
  http://www.virologyj.com/content/8/1/412

[annew]

Very interesting, Rollo. Fortunately no colour-breaks seen in any of my flowers yet, but I'll be watching like a hawk.