Cut Chrysanthemum
Botanical Name - Dendranthema grandiflora
Family - Asteraceae

• Standard types   Bonfire Orange, Bonfire Yellow.
• Spray types         Reagan Yellow, Reagan White, Nanako, etc.,

Soil –

• Cut chrysanthemums are grown under polyhouses with the following environmental conditions.

Climate- 

• Temperature : 16 – 250C
• Relative humidity : 70 – 85 %
• Carbon dioxide : 600 – 900 ppm
  Photoperiod :
• Long day conditions with 13 hours light & 11 hours darkness during vegetative stage (upto 4-5 weeks from planting) 
• short day conditions with 10 hours light & 14 hours darkness during flower bud initiation stage.

• Terminal cuttings and tissue culture plants are used.
• Terminal cuttings are widely used for commercial cultivation.
• Cuttings of 5-7 cm length are taken from healthy stock plants and are induced to root by treating with IBA (1000 ppm).

• Beds of 1 m width, 0.3 m height and convenient length are formed.
• Nets (with cell size depending on the spacing adopted) are placed on the beds and planting is done.

15 x 15 cm (45 plants/m2)  or 10 x 15 cm (67 plants/m2)

Drip irrigation with 8-9 litres of water/m2 /day

Basal application of DAP – 50 g/m2
Weekly schedule – from 3rd week after planting

1.Pinching

• First pinching – 3 weeks after planting;
• 2nd pinching – 5 weeks after planting.
• Disbudding
• In spray varieties, only the large apical bud is removed and the lateral buds are retained.
• In standard varieties, the lateral buds are removed and only apical buds are allowed to develop.

2.Light regulation

Chrysanthemum is highly influenced by light and hence photoperiod should be regulated. (Photoperiod should be regulated as detailed under ‘climate‘)

Growth regulators
Spray GA3 (50 ppm) at 30, 45 and 60 days after planting to increase flower stem length.

Weed management
Weeding and hoeing are done manually as and when required.

1.Chrysanthemum aphid: Macrosiphoniella sanborni

Symptoms of damage

• Nymphs and adults suck the sap from under surface of leaves and terminal shoots.
• Stunted growth of the plant
• Curling of leaf
• Withering of flowers.

Management

• Aqueous spray application of Vercillium lecanii (Vertilec) @ 15 g/lit (108 CFU/g)
• Application (ultra low volume) of the entomogenous fungus V.lecanii
• Neem formulations can be used in rotation with regular insecticides
• Spray any following insecticides malathion 50 EC @ 1 ml/l of water

2.Thrips: Microcephalothrips abdominalis

Symptoms of damage

• Infest the flower heads.
• Lacerating the sepals and petals causing abrasions
• Heavy infestation – damage to corolla, stamens
• leading to premature flower drop.
• It transmits the tomato spotted wilt virus, necrotic spot virus to many floricultural crops.

Management

• Grow resistant varieties like Chandrika, Bangalore Local Yellow Double, M-7, Pankaj and Yellow Star.
• Yellow or blue sticky traps can be used for mass trapping of thrips.
• Blue traps – more effective for mass trapping than yellow traps.
• Spray dimethoate 30 EC @ 1 ml/litre or fenitrothion 50 EC @ 1.0 ml/litre malathion 50 EC @ 2 ml/litre
• Application of spinosad very effective against thrips .

3.Flower feeder: Helicoverpa armigera   

Symptoms of damage   

• Caterpillars feed on buds and flowers.

Management

• Field sanitation
• Collect and destroy damaged buds and flowers
• Set up pheromone traps with Helilure at 15/ha
• Spray nuclear polyhedrosis virus (Ha NPV) at 500 LE or 1.5*1012 POBs/ha
• Encourage the activity of parasitoids campoletis and chelonus
• Spray carbaryl 50 WP 2g/lit

1.Wilt: Fusarium oxysporum f.sp. chrysanthemi

Symptoms

• Yellowing and browning of leaves.
• Affected leaves die from the base of the plant upward.
• Infected plants are stunted and often fail to produce flower.
• Wilting may cause rotting of root or the base of the stem.

Management

• Before planting dipping the rooted cuttings in a solution of Pseudomonas fluorescens @2g/litre of water.
• Since the disease spreads mostly through cuttings, it is important to use disease free planting material.
• Disease can further be minimized by following strict sanitation; periodical monitoring; crop rotation and rouging of infected plants.

2.Rust: Puccinia chrysanthemi

Symptoms

• Brown blister-like swellings, which appear on the undersides of leaves.
• These burst open releasing masses of brown, powdery spores.
• Severely infected plants become very weak and fail to bloom properly.

Management

• Early removal of infected leaves/plants helps to prevent the further spread of the disease.

3.Septoria Leaf Spot: Sepotria chrysanthemella

Symptoms

• Leaf spots occur during cool-wet periods of the rainy season.
• Since the pathogens are spread through rain splashes the lowermost leaves get infected first.
• Premature withering of the leaves; the dead leaves hang to the stem for some time.
• When flowering starts the infection occurs on flower buds, which rots completely.

Management

• Destruction of disease debris and avoiding excessive irrigation is recommended.

4.Powdery Mildew: Oidium chrysanthemi

Symptoms

• Infection is more severe in older plants under humid conditions.
• The growth of the fungus on the leaves appears as powdery coating.
• Infected leaves turn yellow and dry out.
• Infected plants remains stunted and fail to flower.

Management

• Good ventilation and proper spacing for free circulation of air is recommended.

Standard types: Flowers are harvested when 2 – 3 rows of rays florets are perpendicular to the flower stalk.
Spray types: When 50% flowers have shown colour for distant markets; when two flowers have opened and others have shown colour for local markets.

Standard types : 67 flower stems/meter square
Spray types : 260 flower stems/meter square