North American Fruit Explorers mailing list at ibiblio

["Rodney Eveland" <reveland@collinscom.net>]

It sure sounds like fire blight. Perhaps you planted your seeds in
contaminated soil,  else it may be some kind of mineral deficiency if
you planted in sterile potting soil. Also are they warm enough? Does
your water have excess minerals (dog urinates on seedlings? ;-)?  I
have 3 zone 3 pears, including Ure, that get black tipped leaves every
summer to some extent and sometimes the entire leaf dies. I usually
use a scissors to cut the "infected" leaves off so as to prevent the
spread if it is indeed some find of infection. I can do this as my
trees are still quite small as I have never fertilized two of them and
the Ure only once and that was in the Fall of 2002. It responded with
18" of growth last summer and now will have to be pruned which can
also make plants catch blight more easily so I will probably not prune
until it returns to 5-8 inches of new growth in a normal year. It is
my understanding that fire blight easily enters tender shoots of
susceptable plants. I am not sure but I think all three varieties I
have are somewhat resistant to blight, but I can't afford to take a
chance by forcing growth with fertilizer as trees don't grow like
grass around these parts. I realize that pruning seedlings  will
probably kill them, but it sounds like they are going to die anyhow.
Maybe you should just plant lots of seeds and then keep (of course)
the survivors that don't die from this "Black Tip" problem. I doubt
that your grow lights have the antibacterial/fungicidal power of
genuine 100% sunshine so unless you are looking for resistant plants
you might want to forget about starting them this early. Tiny insects
such as spider mites?  Just my thoughts.