Asian pears and brown rot.

Asked October 13, 2020, 3:32 PM EDT

I use Imidan and captan on my apples. I have been having trouble with brown rot on my asian pears and some on the apples. Is captan good for brown rot and when should I apply. I use wetable powders. If not captan which fungicide would be good for this. This will be for next year of course. Thanks, I really appreciate this service. I used to call Gary Heilig in Mason is the old days. Bruce Gruner

Ingham County Michigan

6 Responses

It would be good to know what kind of rots you have on your apples so that the spray program can be designed accordingly. If you still have apples and asian pears that you can provide several pictures showing the rot, this will be a big help in diagnosis. Try to get some closeup pictures, and maybe one or two showing how the rot looks on the inside of the fruit. See the example picture.
Also see the following link:
https://plantpathology.ca.uky.edu/files/ppfs-fr-t-02.pdf

Brown rot is not a common problem on apples and pears. Scab, black rot, white rot, bitter rot are the main diseases for these two fruit types. There are a few other diseases that are less common.

Thank you very much. It may be till early next week before I try to send you pics as we are taking off north for awhile. Have a great weekend. BG

Sorry about the delay. I had already made the Asian pears into pear sauce and was searching outside the deer fence for pear mummies and damaged pears. Alas the assorted wildlife seem to have disposed of all of them as I had tossed them over the fence away from the trees. I had an apple pic but couldn't get my phone to email to my email, and I couldn't get my phone to attach it to this email.. For some reason I can't get access to my pics to copy them to my PC. That will have to wait till my PC savvy son is here. If I had to guess from the info you sent it would be bitter rot. So could we proceed accordingly and if the route suggested doesn't work I will sent good pics then. If I could get a cell number maybe I could message them? Thanks, Bruce Gruner

If the only rot that creates mummies is black rot, it would be that. tx BG

Addendum to last email.

Any of the rots can result in mummies, but it is more common with black rot because it is a firm rot. The other two tend to get mushy and drop off the tree.

The pictures are very helpful. This is most likely to be black rot. This disease tends to start in the calyx end of the apple and expand from there. It tends to be a shallow rot. And it tends to be firm and not mushy, however other fungi / soft rot bacteria can move in as secondary invaders and cause a soft rot. The apple with the big rot spot looks a bit like bitter rot. Again, cut the fruit in cross section through the rot. If the rot it is aggressively moving toward the core, this might also have bitter rot in it.

Try to do a thorough job removing mummies and dead wood during spring pruning. Captan is effective against black rot and bitter rot. The coverage time is starting post bloom for black rot and when the fruit are about 1 inch in diameter for bitter rot. Both diseases are favored by wet conditions.


Thanks Bill, Besides the early spray with I didn't do as i usually combine Captan with Imidan and don't want pollinator damage, I will spray later in late summer. Maybe with just Captan. Asian pears were loaded this year, and I had my first harvest of Paw Paws after six years. Have to get more road kill for blowfly bait. (Neighbors Walnut Tree is selective to what It's Jugalone kills. Paw Paws are resistant. )

Thanks again, Bruce Gruner long time supporter of the Extension Service.