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Bacterial canker Botrytis fruit rot Buckeye rot Catfacing Cold Injury Early blight Glyphosate injury Gold flecking Growth regulator injury Leaf mold Oedema Rhizopus canker Septoria leaf blight Southern blight Spotted wilt virus Stem rot Triazine injury Yellow shoulder

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Early blight
Causal agent: Alternaria solani (fungus)
Signs: light to dark brown conidia are borne on olive brown conidiophores
Symptoms: Leaf spots often with darker rings within the spots.
Total image number: 8
It one of the most common diseases of tomato.
The fungus can infect many parts of the plants must most commonly leaves and stems.
The fungus is shown in comparison to a leaf hair and some type of insect in the 2nd row, 4th image.

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Septoria leaf spot
Causal agent: Septoria lycopersici (fungus)
Signs: Raised spore-producing bodies ("pycnidia") when mature can be seen within the spots.
Symptoms: Dark leaf spots often smaller than with early blight.
Total image number: 7
Another common disease in which the fungus can infect many parts of the plants must most commonly leaves and
stems. The fungus produces its spores in a sack ("pycnidium") and they protrude from this sack in a gelatinous ooze
which can be seen in images in the 1st row, 4th image and 2nd row, 1st image.

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Leaf mold
Causal agent: Fulvia fulva (fungus)
Signs: mold growth usually on lower surface of leaf.
Symptoms: Spot are usually yellow to brown on upper leaf surface with moldy growth on the lower leaf surface.
Total image number: 12
This disease is more common in greenhouses but can occur in the field under prolonged humid, wet conditions. The 3rd row of images is from a culture of the fungus showing its spores.

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Stem rot, Timber rot
Causal agent: Sclerotinia sclerotiorum (fungus)
Signs: black survival structures called "sclerotia" (see in culture plates).
Symptoms: a dry stem rot usually with disintegrated pith tissue.
On the stems, notice at the margin between healthy and diseased tissue you will see a copper/brown area on the stem.
Within this area you can see a pattern of alternating lighter and darker copper/brown lines
Total image number: 5

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Southern blight
Causal agent: Sclerotium rolfsii (fungus)
Signs: mustard seed-sized survival structures of the fungus called “sclerotia”
Symptoms: Plants will wilt and eventually die from the root/stem infection.
Total image number: 2

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Bacterial canker
Causal agent: Clavibacter michiganensis subsp. michiganensis (bacterium)
Signs:
Symptoms: Stunted plants, yellowed leaves, pith browning and decay. The leaves also tested positive for Cmm in a separate sample than the pith tissue, each by ELISA.
Total image number: 4

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Tomato spotted wilt (TSWV)
Causal agent: Tomato Spotted Wilt Virus (virus)
Signs:
Symptoms: Plants may be stunted and younger tissue will usually show leaf/petiole symptoms.
TSWV leaf symptoms could be similar to the later stages of 'glyphosate' injury to leaves.
Total image number: 11
Row 1: Leaves with broader, dead areas
Row 2: Leaves with discrete spots
Row 3: Fruit infection

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: herbicide injury
Causal agent: 'glyphosate' ("RoundUp")
Signs: none
Symptoms: Plant foliage, especially new growth, will yellow first and then turn brown and die.
Total image number: 8
1st and 2nd row images are of initial leaf symptoms.
Last row (4 images) are leaf symptoms in later stages of development.

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: catfacing
Causal agent: cold or growth regulator (e.g. 2,4-D)
Signs: none
Symptoms: This is an extreme case of "Catfacing". Catfacing symptoms are associated with adverse growing
conditions during blossoming; the adverse conditions result in poor pollination, which leads to irregularly shaped fruit.
Catface symptoms are most often seen in large-fruited fresh market varieties (although other varieties can also be
affected) and are associated with disturbances in flower production such as low temperature injury 3 weeks before
flowers are mature, especially in early plantings, but also with injury from growth regulators such as 2,4-d. Pruning
and high nitrogen can also aggravate the problem.
Total image number: 3

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: cold injury, likely
Causal agent: cold injury, likely
Signs: none
Symptoms: The dead areas mostly between the veins of the older leaves and at the tips of the
very youngest leaves are due to an abiotic cause, not a pathogenic disease. The pattern of the injury on old and new
leaves indicates the injury occurred at one point in time. The cause could be cold injury or some type of air pollutant
from a heater that is not functioning properly.
Total image number: 8
1st row of 4 images is from a greenhouse sample.
2nd row of 4 images is from a plastic high tunnel structure where there was no artificial heating involved.

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: oedema or edema
Causal agent: physiological accumulation of water in cells
Signs: none
Symptoms: leaves where cells along the major veins are swollen with water.
Sample is from a plastic high tunnel structure.
Total image number: 9

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Fruit rot
Causal agent: Botrytis cinerea (fungus)
Signs: mold often called "gray mold" may be see in infected area.
Symptoms: Decay of fruit often with mold present.
Total image number: 3
Can occur in prolonged wet/cloudy weather.

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Buckeye rot
Causal agent: Phytophthora spp. (fungus)
Signs:
Symptoms: Fruit decay often with darkened rings around the margin.
Total image number: 4

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: yellow shoulder, irregular ripening
Causal agent: several
Signs: none
Symptoms: Internal white tissue, Yellow eye, Yellow shoulder, and Green shoulder appear to represent a range of
symptom severity for a single problem, Yellow shoulder disorder (YSD).
See information at the following web sites:
http://www.oardc.ohio-state.edu/tomato/ysd/ysd.htm
http://www.oardc.ohio-state.edu/tomato/ysd/toledo031.pdf
http://www.oardc.ohio-state.edu/tomato/ysd/newhartzratio.htm
Total image number: 3

Plant: Tomato (Lycopersicon esculentum) (Solanaceae) Back to List
Disease/Disorder: Gold flecking
Causal agent: not known
Signs: none
Symptoms:
See the following reference for investigations into its cause:
http://www.ces.ncsu.edu/fletcher/staff/jmdavis/goldfleck1.html
Total image number: 4