Peach diseases By Allah Dad Khan Provincial Coordinator IPM KPK MINFAL

2. Peach Diseases
A
Lecture To ToT trainees ( FFS)
By
Mr. Allah Dad Khan
Provincial Coordinator IPM KPK
MINFAL Pakistan

3. Peach Brown Rot
Symptoms Brown rot on fruit
 Brown rot, caused by the
fungus Monilinia fructicola, causes the
fruit to rot away while still on the tree. In
its last stages the fruit is entirely brown
and looks whithered and dried out. The
fungus can live in many temperatures
and climates, but it particularly loves
moist climates. The rot can also turn
flowers brown and cause new twigs to
die off.
 To prevent the spread, make sure to
clear away affected fruit, twigs or
flowers. Do not compost the remains, as
the fungus spores can live in compost
and spread to the rest of your garden. A
fungicide can also stop the spread of the
fungus. Good air circulation and a drier
enviornment also helps prevent rot.

4. Peach Brown Rot
Symptoms of brown rot on peach
blossom
Symptoms of brown rot on peach
twigs and blossoms

5. Peach Brown Rot
Symptoms of brown rot on fruits Brown rot on fruit

6. Peach Scab
Cladosporium carpophilum
Symptoms Scab on peach fruit
 Peach scab is caused by a fungus
called Cladosporium carpophilu. It
is most often found in warm, moist
and humid areas, such as in the
South. However, it can affect peach
trees worldwide. The fruit will often
crack and rot within those cracks,
without much affect to the taste of
the fruit. However, scab makes it
harder for the peach skins to slip off
during the canning process.
 To prevent scab, use a chemical or
organic fungicide just as the
blossoms fall of the trees and for
the ensuing month. Pruning and
cleaning up fallen fruit and leaves
will also prevent the continued
spread.

7. Peach Scab
Scab symptoms on peach twigs Scab symptoms on peach fruit

8. Peach Scab
Scab symptoms on peach fruit Scab symptoms on peach fruit

9. Peach Powdery Mildew
Symptoms
 Powdery Mildew is caused
by the fungus
called Sphaerotheca
pannosa and affects both
garden plants and fruit
trees. Leaves often fall off
or develop abnormally,
eventually growing a white
fuzz. An entire harvest can
be ruined by mildew if left
unattended. Consider
purchasing tree varieties
that aren't susceptible to
the disease. Fungicide and
proper area maintenance
are also good preventative
practices.

10. Peach Leaf Curl
Symptoms Leaf curl on peach
 Leaf curl is a fungal
disease caused
by Traphrina deofrmans.
It causes defoliation and
crop loss in practically
every variety of peach
tree. Fungicide
application during the fall
after most of the leaves
have fallen or before
budding in spring can
stop the fungus.

11. Leaf curl
Peach leaf infected with leaf curl Peach leaf curl symptoms

12. Peach Leaf Curl
Peach leaf curl symptoms on
young peach tree
Peach leaf curl symptoms on
foliage

13. Peach Leaf curl
Peach leaf curl symptoms
Peach leaf curl symptoms

14. Peach Bacterial canker
Pseudomonas syringae
Symptoms Canker on peach trunk
 Cankers on twigs at bases of flower and leaf
buds, in pruning wounds or at the base of
spurs which exude amber colored gum;
cankers spread upwards and form sunken
areas in winter; if pathogen enters dormant
buds they may be killed or open normally in
Spring before collapsing in early Summer;
infected buds may be symptomless
 Cause
 Bacterium
 Comments
 Disease emergence favors high moisture and
low temperatures in the spring; young trees
particularly susceptible; trees grown in sandy
soils that drain poorly are also susceptible
 Management
 Ensure that a suitable peach variety and
rootstock is chosen based on geographic
location and environmental conditions to
prevent stress to tree which predisposes tree
to canker disease; apply protective copper
spray to trees before flowering; prune trees in
early summer to decrease likelihood of
infection

15. Peach canker
Canker exuding gum on infected
peach tree
Peach tree with dark cankers on
bark

16. Canker on peach trunk
Canker on peach trunk
Canker on peach trunk (bark
peeled to show discoloration to
tissue underneath)

17. Bacterial spot
Xanthomonas campestris
Symptoms Peach tree infected with bacterial
spot
 Water soaked, angular gray lesions on the underside of
the leaves which turn purple and necrotic in the center
and cause a shot hole appearance if lesion center
drops out; if lesions are present in high numbers on
leaves they may become chlorotic and drop from tree;
cankers develop on twigs either as raised blisters or as
a dark area surrounding a bud that fails to open; in
years of severe infection the entire fruit crop may be
lost; lesions on fruit begin as small brown, water-
soaked lesions which may exude gum
 Cause
 Bacterium
 Comments
 Periods of frequent rainfall during late bloom and early
petal drop increase likelihood of fruit and leaf infection;
infection is rare during hot, dry weather
 Management
 Avoid planting susceptible peach varieties in areas
where disease is known; once disease is visible it can
be difficult to control, protective copper applications in
the Fall prior to leaf drop and/or application in early
growing season may help prevent the disease; care
should be taken as peach trees are very sensitive to
copper


18. Peach Bacterial Spot
Symptoms of bacterial spot on peach
leaves
Symptoms of bacterial spot on peach
leaves

19. Peach Bacterial Spot
Symptoms of bacterial spot on peach
leaf
Symptoms of bacterial spot on peach
fruit

20. Peach Crown gall
Agrobacterium spp
Symptoms
Large gall on trunk of peach tree
 Galls on roots and/or crown of tree which can range in
size from so small they are not visible to the naked eye
up to 10 cm (4 in) in diameter; galls first become visible
as white, fleshy swellings that grow rapidly and become
tan to brown in color; galls typically develop at the site
of a wound and new galls form adjacent to old ones the
next year
 Cause
 Bacterium
 Comments
 Infection with crown gall begins at the site of plant
wounds; disease emergence is favored by poorly-
drained, alkaline soils and previous feeding damage by
nematodes
 Management
 Chemical control of the disease is generally ineffective;
an effective bacterial biological control is available for
commercial production; cultural control methods
include: planting only certified, disease-free material,
planting peach in well-draining soil, rotating infected
fields with a non-host before peach is planted and also
using good sanitation practices

21. Crown Gall
Symptoms of crown gall on trunk of
peach tree Galls on roots of peach tree

22. Crown Gall
Crowm gall symptoms
Symptoms of crown gall on trunk of
peach tree

23. Crown Gall
Gall on peach tree Galls on peach roots

24. Peach Shot hole disease
Wilsonomyces carpophilus
Symptoms
Shot hole lesions on peach fruit
 Brown lesions with purple edge on
fruit, twigs and buds; holes in
leaves due to lesions which have
dried and dropped out; brown
lumps developing in the center of
lesion (visible with hand lens); buds
turning brown or black and exuding
sap; tan lesions with brown margins
which exude sap on twigs
 Cause
 Fungus
 Comments
 Disease emergence favors wet,
windy conditions
 Management
 Application of Bordeaux mixture
before rains in Fall are sufficient to
protect dormant buds and twigs
over winter

25. Shot Hole
Shot hiole symptoms on peach fruit Shot hole lesions on peach fruit

26. Peach Silver leaf disease
Chondrosterum pupureum
Symptoms
 Leaves have a silvery appearance; if infection
is severe the leaves may curl upwards and
become necrotic; death of individual limbs or
entire tree may occur; fungal fruiting bodies
appear on the surface of the dead bark
 Cause
 Fungus
 Comments
 Pathogen is spread via spores released after
rainfall during periods of high humidity and can
enter trees through pruning wounds; risk of
infection is increased if tree is pruned during
late winter or early spring; trees also
susceptible when they are heavily pruned
 Management
 Control of silver leaf disease is difficult and
infection can be widespread after rainfall in
areas where the disease is present; strategies
to reduce the incidence of the disease include:
removing all plant debris e.g. pruning waste,
stumps, and logs; pruning tree during dry
periods and treating large pruning wounds with
fungicidal dressing

27. Phytophthora root and crown
rot
Phytophthora spp.
 Peach tree showing symptoms of
Phytophthora infection

28. Peach Rust
Tranzschelia discolor
Symptoms
Rust spots on peach leaves
 Pale yellow-green spots on both upper
and lower leaf surfaces which are
angular in shape and turn bright yellow
in color; spots on lower leaf surface
develop orange-red spores
 Cause
 Fungus
 Comments
 Fungus overwinters in twigs or in leaves
which remain attached to the tree
 Management
 Rust can be prevented by spraying trees
with protective fungicides; application is
usually carried out one, two and three
months before harvest in areas prone to
early season outbreaks of the disease
and after harvest in areas where disease
is less problematic or emerges later in
the season

29. Peach Rust
Rust symptoms on peach leaves Rust symptoms on peach leaves

30. Plum pox virus
Plum pox virus (PPV)
Symptoms Symptoms of plum pox on peach fruit
 First expanding leaves exhibit chlorotic
veinclearing and veinbanding; lamina
twisted and distorted; fruit show dark
rings, lines and spots; symptoms on fruti
may disappear on ripening; fruit may be
deformed
 Cause
 Virus
 Comments
 Virus is transmitted by aphids but most
common method of spread is diseased
plant material
 Management
 Plant certified healthy material; remove
infected trees from orchard; chemical
sprays to control aphids may prolong
spread of virus


31. Peach Fruittree leafroller
Archips argyrospila
Symptoms
Fruittree leafroller
 Leaves of plant rolled and tied together with
silk webbing; feeding damage to rolled leaves;
defoliation of plant; silk webbing may also be
present on fruits and fruits may have
substantial scarring from feeding damage;
larvae wriggle vigorously when disturbed and
may drop from plant on a silken thread
 Cause
 Insect
 Comments
 Only one generation of insect per year
 Management
 Monitor plants regularly for signs of infestation;
remove weeds from plant bases as they can
act as hosts for leafrollers; avoid planting
pepper in areas where sugarbeet or alfalfa are
grown nearby; Bacillus thuringiensis or Entrust
SC may be applied to control insects on
organically grown plants; apply sprays
carefully to ensure that treatment reaches
inside rolled leaves