Re: [SG] Hand lens/Foliar Nematodes

In a message dated 12/26/98 9:01:21 AM Central Standard Time,
diehlr@INDIANA.EDU writes:

<< Hi Clyde,
 When you say horizontal strips, do you simply mean crosswise strips? How
 wide should the strips be? What is the purpose of cutting and placing in
 water--can't you just examine the whole leaf (still on the plant) with the
 lens? What temperature should the water be? Do the nematodes move at all?
 Tell us more! Thanks, >>

Bobbi, below is some information that may help:
Symptoms can go unnoticed if hostas are inspected after a fall frost. The
symptoms are best detected during an early fall inspection, before hosta
leaves are wilted by frost. It is very important to confirm the presence of
this serious problem in your hosta by actually seeing the creatures.  C.H.
Falstad, American Hosta Society, Scientific Chairman, suggests the following
method: Remove the symptomatic leaf. Cut into strips about 1 cm wide going
across the veins, or widthwise.  Let these strips sit in about 100 to 200 ml
of water for about 1 hour.  Take a funnel with as narrow an opening as you can
find and plug the bottom.  After the hour, pour this water into the funnel.
Let the water sit for about 1 minute and remove by eyedropper about 5 ml of
the bottom portion. The nematodes come out with water and sink, so make sure
this is the water you get.  Drop the water onto a clean clear glass plate.
Top-light the water and hold it over a black sheet of paper. View with a 10 X
hand lens. If you have an infestation you may see very thin white filaments
squiggling back and forth like worms getting put on a fishing hook.

Ray Rodgers, CIHS, Bartonville, IL
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index