Tomato physical disorders By Mr. Allah Dad Khan Provincial Coordinator IPM KPK MINFAL Islamabad

2. Tomato Physiological
Disorders
ToT to FFS Staff
By Mr. Allah Dad Khan
Provincial Coordinator IPM KPK
MINFAL

3. symptoms Physiologic Leaf Roll
 Leaf roll is a physiological disorder of
tomatoes that is most commonly
associated with hot dry weather, but can
occur in response to other stresses like
fast growth, high production, and pruning.
Leaf margins roll upward until they touch
or overlap in an almost tube like fashion.
Affected leaves are firm and leathery to
the touch. This disorder is believed to be a
strategy to conserve moisture. Lower
leaves are commonly affected first. Once
leaves roll, they will not unroll even if
weather conditions become cool and wet.
In severe conditions the entire plant may
exhibit leaf roll. Leaf roll does not
noticeably reduce plant growth or yield.
Some varieties exhibit leaf roll more easily
than others. Leaf roll is very common in
tomatoes grown in hoop houses.
Physiologic leaf roll

4. Symptoms
 Plants fail to set fruit. Cause: Extremes in
temperature and dry conditions may
result in poor pollination and cause the
flowers to drop from the plant without
setting fruit. Blossom drop on tomatoes
occurs when night temperatures are below
55 F or above 75 F. Control: Water the
plants deeply once a week during dry
weather. Fruit set should increase when
temperatures moderate. Hormone sprays,
such as "Blossom Set", may prevent some
blossom drop due to low temperatures.
However, the resulting fruit are often
misshapen. Hormone sprays do not
prevent blossom drop due to high
temperatures
Blossom Drop

5. Symptoms Blossom end rot,
 Blossom-end rot is one of the most
common tomato disorders seen in
Minnesota. Affected fruit have a tan
to black flattened spot at the blossom
end of the fruit. Secondary fungi and
bacteria can enter the blossom end
rot area, resulting in further decay of
the fruit. Blossom end rot can appear
on fruit in any stage of development,
but it is most common when fruit are
one-third to one-half grown. The first
fruit produced by the plant are often
most severely affected. Fruit that
develop later in the season on the
same plant can be unaffected.
Blossom-end rot

8. Blossom end rot
 In tomatoes and peppers, blossom end rot produces a symptom
of a black, concave lesion which looks at first sight like a fungal
disease.
 It is caused by an imbalance between potassium and calcium in
the soil or compost.
 It occurs most often when the soil or compost is allowed to dry
out while the fruits are swelling.
 It is most common when plants are raised in grow bags, where
they have a small, shallow root run that dries out easily.
 Although there is no cure for blossom end rot once the symptoms
begin to appear, the obvious recommendation is that fruiting
crops should never be allowed to have dry roots.

10. Symptoms
 The outer wall of the fruit is
normal, but the tomato is
hollow inside. One of the seed
cavities is usually empty.
Cause: Extreme high or low
temperatures, excessive
nitrogen fertilization, and
heavy rains may interfere with
normal pollination, resulting
in puffy fruit. Puffiness occurs
most frequently on early fruit.
Control: No effective controls.
Puffiness should decline later
in the summer
Puffiness

11. Symptoms Sunscald,
 Sunscald, H. Schwartz, Colorado State University
Copyright info
 Sunscald occurs on tomato fruit that have been
exposed to too much sun. This is common in
plants that are suffering leaf loss from a leaf spot
disease or insect feeding, but can also occur on
plants that are over pruned or on fruit that are
otherwise exposed to the sun.
 Sunscald results in a pale yellow to white spot on
the side of the fruit facing the sun. This area may
become a flattened, grayish-white spot. The
surface may dry out to a paper like texture.
Sunscald spots are frequently invaded by decay-
causing fungi and bacteria that further rot the
fruit.
 The best way to avoid sunscald is to maintain a
healthy tomato plant through management of
insect and disease pests that defoliate tomatoes.
Sunscald

14. Symptoms Growth crack
 Growth crack, M. Grabowski
 Growth cracks result from extremely rapid
fruit growth. This may be brought on by
periods of abundant rain and high
temperatures, or can occur when water is
suddenly available to the plant through
rain or irrigation after a period of drought.
Cracks may radiate from the stem end of
the fruit or may encircle the fruit. Cracks
are often invaded by secondary fungi and
bacteria that further rot the fruit.
 Maintaining even moisture by watering
regularly and mulching the soil around the
tomato plant can help reduce growth
cracks. Varieties differ in susceptibility to
cracking, and variety descriptions may be
helpful in choosing a plant less likely to
crack.
Growth cracks

15. Symptoms Catface
 Catface is a condition involving malformation
and scarring of fruits, particularly at the blossom
end. Affected fruit are often somewhat flat with a
corky brown scar covering the base of the fruit.
Catfaced fruit can have cavities extending deep
into the flesh.
 Catface, M. Grabowski
 The causes of catfacing are not definitely known,
but it is generally agreed that any disturbance to
flowers or flower buds can lead to abnormally
shaped fruits. Cold temperatures and contact
with hormone-type herbicide sprays are
commonly believed to be responsible for catface.
 Catface, M. Grabowski
 Large fruited tomatoes are more susceptible to
catface than small fruited tomatoes. In addition
some varieties are particularly prone to catface
and should be avoided if catface has been a
problem in the past.
Catface

16. Symptoms Herbicides injury
 Tomatoes are very sensitive to injury
from broadleaf herbicide chemicals.
These are commonly used for
controlling weeds like dandelions,
plantain and clover in home lawns.
The most common injury symptoms
observed are caused by phenoxy
herbicides such as 2,4-D (2,4-
dichlorophenoxyacetic acid) and
dicamba (substituted benzoic acid).
These chemicals are growth
regulator, hormone-type weed
control chemicals. Tomato plants
usually come in contact with the
chemical through spray drift or the
use of a sprayer that was previously
used to apply the herbicide
Herbicide injury

18. Symptoms
 bruising is caused when the tuber
is impacted. The skin doesn’t
break, but internal tissues are
damaged leading to the
formation of the pigment
melanin, which will make the
damaged area appear black, or
dark to light grey. This can be
anywhere on the tuber, but is
more prevalent at the stolon end,
and where the tuber is more
curved.

 -
Bruising or blackspot

19. Symptoms
 Growth dwarfed,
thin and upright
habit; stem and
petioles rigid;
leaves pale green,
occasional purplish
tints, older leaves
yellowing.
TOMATO PLANT Nitrogen deficiency

20.  Growth dwarfed
and thin; leaflets
droop, curl
backward and
develop strong, dull
purple tints
TOMATO PLANT Phosphorus deficiency

21. Salt Damage Phosphorus Deficiency
Physiological Disorders

23. Symptoms
 Death of growing
point and die-back
of main stem from
tip; die-back of
leaves, progressing
from terminal
leaflets and of
flower and fruiting
trusses
TOMATO STEM Calcium deficiency

24. Symptoms
 Dying off of
terminal leaflets
and flowers; leaves
purplish brown
tinting.
TOMATO TRUSS Calcium deficiency

25. Symptoms
 Dying back of
trusses and
"Blossom End Wilt"
of distal fruitlets.
Calcium deficiency

26. Symptoms
 Central intervenal
chlorosis and green
marginal bands
TOMATO LEAF Magnesium deficiency

27. Symptoms
 Leaves intervenal
chlorosis and
necrosis; fruits
show "Green Back".
TOMATO TRUSS Magnesium deficiency

28. Symptoms
 Greenhouse view.
Leaves intervenal
chlorosis and
necrosis.
TOMATO PLANTS Magnesium deficiency

29. Symptoms
 Leaflets slight
marginal and
intervenal chlorosis
followed by brown
marginal scorching;
scorched margins
curled foward
TOMATO LEAF Potassium deficiency

30. Symptoms
 "Blotchy Ripening";
green and yellow
areas merging into
red color of surface.
(cf. Plate 260,
mosaic fruits)
TOMATO FRUIT Potassium deficiency

31. Symptoms
 Virus Disease.
Blotchy uneven
ripening, similar to
"Blotchy Ripening"
due to potassium
deficiency but blotchy
areas more sharply
defined. (cf. Plate
259, potassium
deficiency)
Virus Disease

32. Symptoms
 Tip leaves,
especially basal
areas of leaflets,
intense chlorotic
mottling; stem near
tip also yellow
TOMATO FOLIAGE Iron deficiency

33. Symptoms
 Intervenal chlorotic
mottling distributed
over entire surfaces
of leaflets; mottled
areas become
necrotic
TOMATO LEAF Manganese deficiency

34. Symptoms
 Stem and petioles,
especially nodal
areas, necrotic
lesions; leaves
wither and hang
down
acidity complex

35. Symptoms
 Stems stiff;
terminal buds die
and growths die
back; lateral shoots
developed, giving
plant flat top; leaves
highly tinted
purple, brown and
yellow.
TOMATO SHOOT Boron deficiency

36. Symptoms
 Fruits pitted and
corky areas in skin;
ripening uneven
TOMATO FRUITS Boron deficiency

37. Symptoms
 Leaflets somewhat
chlorotic, strongly
incurled and die
back from tips
TOMATO PLANTS Molybdenum deficiency

38. Symptoms
 Left: healthy leaf
receiving
molybdenum.
Right: Molybdenum
deficient leaf;
leaflets, incurled
margins, intervenal
chlorotic motting
and death of tips
TOMATO LEAVES Molybdenum deficiency