Madman2001 said:

Folks:

We have Fusarium wilt in our vegetable garden, at least in the south
end. I have some questions.

1) If I don't plant susceptible plants there for 3 or 4 or 5 years,
will the wilt pathogens die off? Or is forever?

"Fusarium fungi survive in the soil or associated with plant debris for up to ten
years. Disease development is favored by warm soil temperatures, and symptoms
are most prevalent when temperatures range from 80-90 degrees F. The fungi enter
the plants through their roots and are then spread throughout the plant by the plant's
water-conducting vessels."


2) Will the pathogens spread throughout the garden by themselves or
thru natural causes (e.g. rain), or must they be carried by tools,
shoes, etc.

I would think that tools, shoes, and tillers move the fungus around
faster than natural causes.


3) How can I clean my tools to prevent me spreading the dirt until my
whole lot is infected?

"A thorough cleaning with water will reduce most risk of transmitting the disease."

I would hazard that a final dip in a 10-1 dilution of bleach in water would make
the gardener feel even more secure.

4) Gardens Alive advertises a natural agent that attempts to
outcompete the wilt

Has anyone tried this?

I haven't.

5) Am I doomed never to grow Brandywines or Green Zebras again??

Well, you could always grow them in large planters or raised beds filled
with 'clean' soil.

The earlier quotes were from the following website:

http://www.mobot.org/gardeninghelp/i...%20Wilt%20of%2
0Tomato.shtml

A longer quote (including an intriguing mention of a soil fertility problem that
might encourage the disease):

/quote begins/
Integrated Pest Management Strategies

1. Plant resistant varieties. These varieties are labeled VF and include
cultivars such as ‘Spring Giant’, ‘Burpee VF’, ‘Supersonic’, ‘Celebrity’,
‘Manalucie’, ‘Better Boy’, and ‘Small Fry’.

2. Remove infected plants from the garden. Removal of infected plants will
help limit the disease's spread. Soil sterilization or fumigation will eliminate wilt
fungi from the soil but are impractical for home gardeners. Soil replacement
should be considered.

[PK comment: Solarization may be worth a try, though, as replacing the soil would
be a lot of work and expense.]

3. Avoid over application of high nitrogen fertilizers. High soil nitrogen levels
accompanied by low potassium levels can increase susceptibility to the fungus.
Use a soil test to determine potassium levels and other nutrient deficiencies.

4. Avoid activity in wet plantings. Movement of wet soil from place to place
via shoes or tools will spread the disease.

5. Sanitize stakes and tomato cages at the end of the season. Avoid using
soil-encrusted tools and supports season after season. A thorough cleaning with
water will reduce most risk of transmitting the disease.

6. For four years, do not plant solanaceous plants in the area where infection
occurred. Tomato, potato, pepper, and eggplant are all susceptible to the disease
and may allow its survival year after year in the same planting area.

/end qoute/

[PK comment: This last recommendation seems optimistic, given that the disease
can persist 10 or more years.]

--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)