North American Fruit Explorers mailing list at ibiblio

[Douglas Woodard <dwoodard@becon.org>]

Some years ago the Pomona had an item about a Brazilian peach which is 
resistant to brown rot. I talked about it to a breeder at the Vineland 
station near me. He told me that they were doing breeding of canning 
peaches with its pollen which they had obtained from California where 
there was an active breeding program using the Brazilian peach. He also 
said that they were only working on canning peaches because the 
Brazilian peach was a rubbery fleshed type which would need several 
generations to get the brown rot reistance into a good quality fresh 
eating freestone peach. I haven't heard anything about this work since.

I have been told by a grower that thinning peaches when the pit is still 
jelly-like results in the pit rotting quickly on the orchard floor and 
not carrying the brown rot infection over to the next year (at least 
from that source). If you thin when the pit has hardened it does not rot 
away completely and will carry the infection to the next year. This 
makes the thinning of very early peaches difficult; apparently if you 
thin early you get more split pits  - harbouring rot and unsaleable - 
which earlies are prone to anyway.

I believe the Harrow apricots were also selected for brown rot 
resistance to a degree.

Alan Haigh wrote:
[snip]
>  
> I'm also curious about brown-rot resistance in stone-fruit.  This is 
> going to be very regionally specific, I'm afraid, but maybe we can all 
> learn something.  I have read that the Seneca plum is resistant but not 
> found this to be true.  I have observed that in peaches older varieties 
> seem to have more resistance.  Encore, Autumn Glo and Lady Nancy tend to 
> rot without significant protection but Elberta and Belle of Georgia do not.
>  
> In southeastern NY earlier ripening stone-fruit that face less heat and 
> humiditity suffer less from brown-rot and peaches less from scab.
> So many of the newer peaches are highly susceptible to brown-rot that I 
> think we should limit the discussion to what's resistant, not what's 
> not, unless it's a variety that seems to exist to rot.  In newer 
> peaches, varieties from the Harrow series are evaluated for brown-rot 
> resistance but they are falling out of popularity.

[snip]