DISEASE-RESISTANT TOMATO VARIETIES
Select the right disease-resistant varieties to ensure your plants survive.
Plant breeders have created varieties with built-in resistance to certain diseases. Although picking the right plant is the first step to a disease-free garden, you must also take other precautions to ensure your plants thrive.
Here is a comprehensive code-chart to help you navigate through the disease-resistant varieties.
We carry some of these plants in our store, so make sure to check out our plant list for current items that can help you keep your tomatoes disease-free!
Tomato Disease Resistance Codes
CODE
DISEASE
DESCRIPTION
A or ASC
Alternaria Stem Canker
This fungus shows up as brown or blank cankers that attack
tomato stems, leaves, and fruit, often accompanied by streaks.
Left unchecked, cankers can spread across the entire plant and kill
it before harvest.
F
FF
FFF
Fusarium Wilt
Fusarium, Races 1 and 2
Fusarium Wilt 1, 2, and 3
First signs are yellowing and wilting on one side of the plant—a
leaf, single shoot, branch or several branches. Yellowing and
wilting move up the plant as the fungus spreads, clogging waterconducting
tissue in the stem and affectively starving the plant.
Left unchecked, fusarium wilt can kill tomato plants well before
harvest time. Unfortunately, some fusarium fungi have overcome
the initial “F” resistance attributes in designated tomatoes. Today,
newer cultivars have been bred to be resistant to secondary
fusarium strains—hence the “FF” and “FFF” designations.
N
Nematodes
Parasitic round worms that often lie dormant in the soil.
Nematodes can produce root galls on the plant up to an inch wide.
Affected plants are weak, stunted, do not respond to fertilizer, and
tend to wilt.
St
Stemphylium Grey Spot Leaf
A fungus that grows brown to black spots on leaves, which
progressively get bigger, turn gray, and drop out—leaving holes.
T
Tobacco Mosaic Virus
Causes mottling and yellowing of leaves, resulting in reduced size
and yield of fruit, as well as turning the fruit brown.
SWV
Tomato Spotted Wilt Virus
Symptoms may vary from plant to plant, but can include yellow
and brown rings on stems, brown streaks on plant stems, dead
leaf spots and tips, and severely stunted growth. Fruit may be
discolored at maturity.
V
Verticillium Wilt
The fungi work their way up through the plant’s roots, clogging
water-conducting tissue in the stem. They spread a toxin that
wilts leaves and prevents water from reaching branches and
leaves, starving the plant. Yellow spots appear on lower leaves,
followed by brown veins. Leaves then turn brown and fall off.
Infection pattern often resembles a V-shape.
