This document provides information on pests, diseases and their management in chrysanthemum. It discusses common pests like aphids, thrips, leaf folder, and bud borer. It also discusses diseases such as rust, powdery mildew, septoria leaf spot, alternaria leaf spot, and verticillium wilt. For each pest and disease, it describes symptoms and provides recommendations for management including chemical and biological control methods. The document is a comprehensive guide covering all major pests and diseases affecting chrysanthemum cultivation.

1. Pests and Diseases of Chrysanthemum
PERUMAL, R.
2016603110
M. Sc., Floriculture & Landscaping

2. About Chrysanthemum…
 Dendranthema × grandiflora
 Asteraceae, n=9
 Europe and Asia
 Queen of East, Autumn Queen, Glory
of east, guldaudi, Pot Mum
 National flower of Japan
 Chrysanthemum city: Ju-Xian (China)
 Head / Capitullum, Ray & Disc florets
 Short day plant – ‘Photo sensitive’
 Sensitive to water-logging
 Terminal cuttings and suckers
 Planting: April-May
 15 x 15cm (45 plants / m2)
 NPK @ 20:20:10 g / m2
 Pinching & Disbudding
 Yield: 270 sprays / m2
 2% sucrose + 1200-4800 ppm AgNO3
increased the vase-life from 12 to 20 days
 Quilling of petals, Petal bum (B deficiency),
Bleaching of petals

3. Chrysanthemum
Pest
 Aphids
 Thrips
 Leaf Folder
 Leaf Miner
 Bud Borer
 Red Spider Mite
Diseases
 Rust
 Powdery Mildew
 Septoria Leaf Spot
 Alternaria Leaf Spot
 Verticillium Wilt, Fusarium Wilt
 Grey Mould
 Flower Blight
 Root Rot
 Bacterial Blight

4. Pests

5. Aphids
Myzus persicae, Macrosiphoniella sanborni
Suck the cell sap from growing
shoots & lower surface of leaves
Greenish – black nymphs
Chocolate – brown adults
 Loss of vigour
 Yellowing
 Premature leaf fall
 Stunted growth of plant
Adults Sucking plant
fluids from veins
Inhibits photosynthesis by reducing
amount of light reaching the leaves

6. Aphid infestation on leaves and flower of chrysanthemum

7. Management:
Spray Pongamia or neem oil at 20ml/l
4% Pongamia kernel extract at 10-15 days interval
Spray Dimethoate 30 EC @ 2ml/l
Oxydematon methyl 25 EC @ 2ml/l
Acephate 75 SP @ 0.5 g/l
Application of Verticillium lecanii @ 3 g/l
Release of I day old Chrysoperla carnea larvae
@ 50:1 ratio eliminated aphid population
(Scopes, 1969)

8. Thrips
Microcephalothrips abdominalis, Frankiniella spp.,
spp.
Silvering
Mottling
Distortion of leaves
Damaged flowers:
Discoloured
Withered & dried
scorching
Slender white nymphs &
Black adults
Feed on tender leaves
Rasping & sucking mouth parts
Cannot penetrate deep into plant tissue
Found throughout year
Female thrips live: 30 – 40 days (150-300 eggs)
Spreading tomato spotted wilt virus

9. Thrip damage on flowers of chrysanthemum

10. Management:
Spray Dimethoate 30 EC @ 2ml/l at 15 days interval
Severe, spray Ethofenprox 10 EC @ 1ml/l
Fipronil 5 SC @ 1.5 ml/l
Covering of young buds with polythene bags with holes prior to blooming
protects flowers from attack by thrips (Wang & Lin, 1984).

11. Leaf Miner
Liriomyza trifolii
Severe in March – June
Larvae feeding on mesophyll leaving
characteristic trails
Severaly damaged leaves,
show extensive mining which turn
brown and dry up
Leaf miner infestation on
chrysanthemum leaf

12. Management:
Remove and destroy
Spray Triazophos 40 EC @ 1.5 ml/l
Abamectin 1.9 EC @ 0.4 ml/l
Spray with Dichlorovos 76 EC @ 1 ml/l
Decamethrin 2.8 EC @ 1 ml/l
Dipping of chrysanthemum cuttings in 3% Margosan
(neem formulation) for 2 hrs and foliar spray of the
same botanical @ 0.4% reduce the pupae & adults
(Lindquest et al., 1986)
Install yellow sticky traps coated with
Chlopyriphos 20 EC @ 2.5 ml/l to trap
adult population
Adults
Larvae

13. Bud Borer
Helicoverpa armigera (Nocturnal moths)
Feed on very young terminal shoots
Young foliage & Flower buds and heads.
Evidence: round holes in buds & flower heads
Bud worm
larvae
Feed for 2 – 3 weeks in warm weather
Eaten enough, they leave plant &
burrow in soil – pupate.
Adult moth
Each female lay up to 1000 eggs
deposited on new leaves.
Larvae tunnels its way into the
buds and feed on developing
flower parts

14. Bud Borer infestation on
chrysanthemum
Management:
Collection & killing of grown up
larvae
NSKE 4% / neem oil 1% sprays
Spraying Methyl parathion 0.05%
Ethofenprox @ 0.01%

15. Red Spider Mite
Tetranychus urticae
Red Spider Mite is a profuse web-spinner in its
active stages
Mite colonies, seen on upper surface of leaves
Damage starts in March & reaches peak during
April - July
Affected leaves, discoloured
wilt and fall off damaging shoots
dry up

16. Management:
Removing and burning of infested shoots
Spray Dicofol 18.5 EC @ 2.5 ml/l
Dimethoate 30 EC @ 2 ml/l
Profenophos 50 EC @ 1 ml/l
Spray with Pongamia / neem oil @ 1%

17. Diseases

18. Septoria leaf spot
Septoria chrysanthemi
Symptoms:
Lower leaves are infected first
Spots: first yellowish then become dark
brown & black
Severe infected leaves are prematurely
wither & drop off from the plant
Disease develops rapidly in cool wet
weather
Spores of fungus are spread by
splashing water

19. Management:
Regularly clean up & destroy debris
Avoid splashing water into plant foliage
Spraying of 0.1% Carbendazim (effectively
control)
Fungicides:
Chlorothalonil
Mancozeb
Myclobutanil
Thiophanate methyl
Capton

20. Alternaria Leaf Spot
Alternaria spp.
Symptoms:
Pathogen cause small dark brown spots
with yellow surroundings.
Spots merge & leaves begin rot.
Severe infection results,
withering of leaves
dead leaves hanging to the stem
Finally death of the entire leaf
Management:
Spraying Mancozeb / COC each @ 2 g/l

21. Wilt
Verticillium albo-atrum
Symptoms:
Foliage becomes yellow & wilted
Leaves begin to die from the base of
the plant upward
Stems may exhibit dark streaks in the
vascular system
Infected plants,
stunted & fails to produce flowers
Favored when cool weather is followed
by hot.

22. Management:
 Pathogen - free cuttings
 Use resistant cultivars
 Continuous cropping in sick soil should be
avoided.
 Soil drenching with 0.2% Carbendazim
Avoid susceptible cultivars:
Echo
Glowing Mandalay
Mountain peak
Paragon
Pert
Wedgewood

23. Fusarium Wilt
Fusarium oxysporum var. trachaephilum
Symptoms:
Yellowing of foliage, stunting and
wilting
Stems show reddish brown
discolouration of vascular system
Fusarium is spread in contaminated
soil & from infected cuttings and is
favored by high temperature, high RH,
over watering & poor drainage

24. Management:
Pathogen - free cutting & pasteurized
growing media
Adjust pH 6.5 – 7.0
Use of nitrate nitrogen fertilization
Avoid susceptible cultivars:
Bravo
Orange bowl
Royal trophy
Yellow delaware

25. Grey Mould
Botrytis cinerea
Symptoms:
Occur on petals, leaves or as a stem
canker as brown, water soaked spots.
Infected plant parts covered with grey
to brown, powdery masses of spores.
Senescing tissues are most
susceptible
Favored by extended periods of
cloudy, humid & weather.

26. Management:
 Practice good sanitation
 Avoid wetting flowers when watering & do not over crowd the
plants
 Provide good air circulation
 Keep humidity low by combination of heating & venting
 Fungicides:
Chlorothalonil
Mancozeb
Fenhexamid
Thiophanate methyl

27. Flower Blight
Stemphylium lycopersici
Symptoms
Infection is noticed on calyx & petals in
the form of necrotic brown spots.
Infected flowers wither & die
Causes small, necrotic, light brown to
dark brown lesions (cause blossom
death)
Favored by wet conditions &
temperatures between 60⁰-85⁰F
Management
Rouge & dispose of infected plants
Provide good air circulation
Avoid overhead irrigation &
keep plants dry
Spraying 0.1 – 0.2% Mancozeb /
0.1% Benomyl

28. Powdery Mildew
Erysiphe cichoraceum
Symptoms
White to ash – grey powdery
growth on leaves & stems
Foliage become puckered or
disorted
Infected leaves will shrivel & die
Most serious during hot, humid
weather
Management
Proper plant spacing
Good air circulation & Low RH, adequate
light levels
Apply fungicides:
Myclobutanil
Triadimefon
Potassium bicarbonate
Thiophanate methyl

29. White to ash – grey powdery
growth on leaves

30. Rust
Puccinia chrysanthemi, Puccinia horiana
Symptoms
Puccinia chrysanthemi:
Minor damage
Defoliation and reduced flower
production
Puccinia horiana: White rust
Green house crops
Whitish yellow to green lesions on
upper leaf surfaces
Rust results,
leaf distortion
discolouration
defoliation & plant death
Management
Infected plants to be destroyed
Resistant varieties:
Achievement
Copper Bowl
Miss Atlanta
Powder Puff
Orange Bowl

31. Pustules of chrysanthemum white rust
on lower surface of chrysanthemum leaf.

32. Root Rot
Pythium spp., Phytophthora spp.
Symptoms:
Infected plant parts (root, stem & leaves)
Management:
Good drainage conditions to prevent
logging
Soil drenching with Mancozeb @ 2 g/l

33. Bacterial Blight
Erwinia chrysanthemi
Symptoms:
Water soaked lesions & Pith becomes
jellylike
Death of buds & stems & Blackening of
terminals & wilts
Favored by high temp. & RH
Management:
Use disease free cuttings
Dip in streptomycin
Reduce humidity

34. Nematodes
 Lesion Nematode
 Bud and Leaf Nematode
 Root – Knot Nematode
 Sting Nematode
Lesion Nematode, Pratylenchus chrysanthus
Edward et al.,(1969)
Common above ground symptoms
Reduce flower size
Management:
Application of neem cake enriched
with T. harzianum @ t/ha
 Root – Knot Nematode, Meloidogyne spp.
M. arenaria & M. javanica have been reported
on chrysanthemum (Chandawani et al., 1967)

35. Bud and Leaf Nematode
Aphelenchoides ritzemabosi, (Gill & Sharma, 1976)
Interveinal discolouration
Infested leaves shrivel, hang down as the
leaf dies.
The nematode escape through stomata &
migrate in surface water films to infect
terminal flower buds which produce
deformed and under sized blossom.
 Dipping of chrysanthemum stools in
0.03% Parathion for 20 mins.
 Hot water treatment (48⁰c for 5 mins)

36. Reference
 Integrated Pest and Disease Management in Horticultural Crops, P. Parvatha Reddy
 Advanced Commercial floriculture, S.K. Battacharjee and L.C. De
 Production Technology of Commercial Flowers, L.C. De

37. Thank you…