Diseases and Pests of Flower Crops
Authors: Poonam Kumari, Thaneshwari and Sapna Panwar
Division of Floriculture and Landscaping
ICAR- IARI New Delhi- 110012
Correspondence address: poonamjaswalfls@gmail.com


  1. Flower crops are attacked by several pests and diseases.
  1. Several pests act as vectors for various diseases which cause considerable yield loss.
  1. Chemical control is expensive, time being and health hazardous.
  1. Genetic resistance is the cheapest and the best method of minimizing such losses.
  1. Resistant varieties are developed through the use of resistant donor parents available in the gene pool.
  1. Many crops would have lost their commercial status if resistance to the particular diseases were not available. Initially to obtain resistant varieties knowledge of genetics with respect to pest and disease is essential In pest and disease,
  • Oligogenic resistance
  • Polygenic resistance
  • Cytoplasmic resistance
Plant relation with pest and disease

  • The relationship between a plant and plant pathogen is very complex
  • The ability of a plant pest or pathogen to cause disease in a plant depends on environmental conditions, the properties of the organism itself and the capacity of the plant to defend itself
  • Varieties within a plant species can differ in their ability to defend themselves
  • Under different climatic conditions the interaction between the same plant and plant pathogen may have different outbreak
  • Plant pathogens are known to develop and form new races or strains that can cause damage to plants that remain unaffected by the original form of the pathogen
Resistance is the ability of a plant to restrict the growth and development of a specified pest or pathogen or the damage they cause when compared to susceptible plant varieties under similar environmental conditions and pest or pathogen pressure (ISF, 2010).

Resistant varieties

A variety is known to be resistant, if the pest cannot eat it, or cannot live or multiply on it. Thus, if a plant is resistant against a pest, it will not suffer any damage from that pest.



  • Resistant varieties offer cheapest means of disease control as they do not involve in any recurring expenditure to farmer
  • Resistant varieties obviate the use of pesticides, thereby in reducing the crop production, environmental pollution and health hazards
  • It safeguards against the inadvertent release of such varieties that are more susceptible than the earlier varieties
  • Not affected by environmental conditions
  • It can be used in IPM
  • It helps in protection of natural enemies (Predators & Parasites)



Major diseases

Black spot: Diplocarpon rosae

Powdery mildew: Sphaerotheca pannosa var. rosae

Botrytis blight: Botrytis cinerea

Crown gal : Agrobacterium tumefaciens

Other diseases: Stem canker, Cercospora leaf spot, Rust etc

Major pests: Aphids, Two-spotted spider mite, Scale insects, Thrips (Florida flower and western flower, chili thrips), Beetles and Leaf-cutter bees

Rose varieties resistant to Blackspot:

Angel Face, Ivory Fashion, Proud Land, Carrousel, Miss All-American Beauty, Queen Elizabeth, Duet Mister Lincoln, Razzel Dazzle, Electron, Montezuma, Rose Parade, Europeana, Pink Peace, Sonia, First Edition, Portrait, Tiffany, First Prize, Pristine, Morden Ruby, Tropicana, Gene Boerner, Prominent, Morden Blush, Morden Snow Beauty, Parkland

Hybrid tea: ‘Pride N Joy’

Floribunda: ‘Sexy Rexy’

Grandiflora: ‘Prima Donna’

Roses Resistant to Blackspot :

Shrub : Care Free Spirit, Pink Knock Out, Rainbow Knock Out, Winter Sunset

Floribunda : Rainbow Sorbet, Julia Child

(Prima W. K. Hutabarat , 2012)

Black Spot & Powdery Mildew resistant roses: Moderately resistant varieties

Hybrid tea: ‘Duet,’ ‘Eiffel Tower,’ ‘Grand Slam,’ ‘Jamaica,’ ‘Matterhorn’

Floribunda: ‘Golden Slipper,’ ‘Saratoga’

Grandiflora: ‘Camelot,’ ‘John S. Armstrong,’ ‘Pink Parfait,’ ‘Queen Elizabeth’

Shrub roses: ‘All That Jazz,’ ‘Carefree Wonder’

Black Spot, Powdery Mildew & Cercospora Leaf Spot resistant varieties

Rugosa roses: ‘Blanc Double de Coubert,’ ‘Fru Dagmar Hastrup’ (‘Frau Dagmar Hartopp’) ‘Rugosa Alba,’ ‘Topaz Jewel’

Alba rose: ‘Alba Semi-Plena’

Cercospora Leaf Spot resistant roses

Jeepers Creeper, Ralph’s Creeper, Royal Bonica, Nearly Wild, Betty Prior, Sevillana, Magic Carpet, Easy Livin’, Cherry Meidiland, Pearl Meidiland, Rosa mutabulis, Rosa wichuraiana, First Light, Bonica, Carefree Wonder, Sea Foam, Pink Grootendorst, Nozomi, Red Cascade, Mystic Meidiland, Hansa, Double Delight

Resistance against mites:

  • Grzeszkiewicz and Witaszek (1994) evaluated 26 rose cultivars for cut flower yield and quality and for resistance against T. urticae and reported that Parfait, Lady Rose and Hidalgo cultivars were found most resistant to T. urticae.
  • Dhooria (1999) studied the mite damage on 7 rose varieties under polyhouse condition. Maximum mite damage was noticed on variety Prophyta (53%) followed by Sophire (23%), First Red (17%), Mercedes Long (15%) and Vivaldi (13%) and negligible mite damage was observed in varieties ‘Golden Time’ and ‘Pavarroti’.
  • Hole and Solunkhe (2005) screened thirty rose cultivars for their relative resistance against two spotted spider mite, T. urticae and reported that the cultivar Rajhans recorded the lowest mite population followed by Apsara and Rose Evening.
  • Tinike, Skyline, Confittee, Grand Gala and First Red
    (Dhananjaya Kumar K.S, 2007)
Resistance against thrips:

  • Gahukar (2003) studied the reaction of three rose varieties against thrips under field condition and reported that over 50 per cent infestation was observed in Gladiator; 40-42% infestation in Folklore and 24-25% infestation in Landora during 1996 and 1997.
  • Skyline, Confetti, Tinike, Grand Gala, First Red (Dhananjaya Kumar K.S, 2007)


Major diseases

Fusarium wilt, Foot rot, Basal rot, Leaf spot and Botrytis blight

Major pests

Thrips, Mite and Bud caterpillar

Resistant varieties

  1. Onozaki et al., (1998) developed a line 91BO4-2 by crossing spray type cv. Super Gold with Dianthus capitatus (wild). This line was highly resistant to bacterial wilt.
  2. Ben et al., (1997) reported that cv. Arbel and Scarlette had novel resistance against Fusarium wilt.
  3. Cultivars William Sim and Vermillion Protruding were less susceptible to stem rot amongest the twelve cultivar tested by Guba et al., 1997.
  4. cvs. Krassina, Regina, Fea, Naslada, Line L-169 and Line L-230 (Slavov et al., 2006)
  5. Arbel and Scarlette (Y. Ben-Yephet et al., 1997) CHRYSANTHEMUM Major diseases Fusarium wilt, Rust, Root rot, Powdery mildew, Leaf spot & Flower blight. Major pests Aphids, Bud caterpillar and Thrips Rust resistant varieties: ‘Achievement,’ ‘Copper Bowl,’ ‘Escapade,’ ‘Helen Castle,’ ‘Mandalay,’ ‘Matador, ‘Miss Atlanta,’ ‘Orange Bowl,’ ‘Powder Puff.’ GERBERA Major diseases Foot rot, Fusarium wilt, Blight or Grey mold, Powdery mildew and Phyllody Major pests Thrips and Bud borer Table 1. Gerbera varieties resistant to foot rot ( Phytophthora cryptogea)
Hybrid Florets colour Disc colour Resistance of (Phytophthora cryptogea) Vase life-water days
H 229/3 cream with pink line green Highly resistant 15.2
H 134/8 yellow dark brown Resistant 13.8
H 147/5 light pink with pink line dark brown Resistant 12.7
Cantor Maria and Lenuta Chis, 2006

Table 2. Reaction of gerbera varieties against powdery mildew

Varieties Disease reaction Number of flowers /m2/year Number of sucker /plant / year
Figaro Resistant 143.00 3.80
Marinila Resistant 106.60 4.00
Palmira Resistant 190.00 5.40
Gerbera cultivars resistant to mites

Sirtaki, Rondena, Fame and Bianca (Krips et al.,2001)


Major diseases

Fusarium wilt, CMV (Cucumber mosaic virus)

Major pests

Thrips and Spike caterpillar

Wilt resistant gladiolus varieties

  1. Novalux and White Prosperity resistant cultivars (Dallavalle et al.,2002)
  1. Cultivars Albana, Apricot Glow, Souvenir, Hoppman’s Glory, Sylvia, Dhiraj, White Friendship and White Prosperity are reported to be resistant while Australia Four and Mansore are tolerant to wilt disease (Mc Cullough, 1944; Georgiaand Peikova, 1976; Sezginet al.,1983, Chandra et al., 1985 ; Bajaj et al., 1989).
  2. In gladiolus, out of 11 cv. Tested against the disease cvs ‘IARI Set 1’, ‘Psittacinus Hylo and Sueliton were found resistant (Sharma and Bhattacharjee, 2002). Table 3.Wilt resistant gladiolus varieties
Cultivars Parent Resistance
Arka Amar Watermelon Pink X Aarti Resistant
Arka Kesar Vink’s Glory X Sagar Moderate resistant
Darshan Watermelon Pink X Shirley Moderate resistant
Dhiraj Beauty spot X Psittacinus hybrid Resistant
Kum Kum Watermelon Pink X Lady John Moderate resistant

Major diseases

Collar rot & root rot, Fusarium wilt, Rust, Grey mold and Aster yellows (Virus)

Major pests

Stem borer, Mites and Nematodes

Fusarium wilt resistant china aster varieties

“Heart of France”, “Crego” , “Ostrich”, “Feather”, “ Stardust”, “American Branching”, “Roment”, “Powderpuff” and “Lapplator” (Jones and Riker)

“Srdce Francie” and “Bukett Bila” (Kratka and Duskova, 1991)

Resistant: Matsumoto, Einf. Madeleine and Americka Kraska series

Moderately resistant: Chryzantemokvěte and Standy series, Matsumoto Pink, Princes Armida and Jitka (Nečas and Kobza 2008).

Nematode (Meloidogyne incognita race 1) resistant varieties:

Highly resistant: IIHR-2

Resistant : Shashank, AST-5, IIHR-17 and IIHR-21

Moderately resistant: Poornima (Nagesh et al.,1995)

Rust resistant china aster varieties:

New England Aster (A. nova-angliae): ‘Crimson Beauty,’ ‘Fanny’s,’ ‘Harrington’s Pink,’ ‘Honeysong Pink,’ ‘Purple Dome,’ ‘Wedding Lace.’

Wood Aster (A. dumosus): ‘Wood’s Blue.’


Major diseases

Basal rot

Major pests: Aphids, Thrips ,Bud borer and Root knot nematode

Resistant tuberose varieties

Nematode (Meloidogyne incognita) resistant varieties:

Shringar : resistant

Suvasini : moderately resistant


Major diseases

Wilt : Fusarium solani

Stem rot : Rhizoctonia solani

Leaf blight : Colletotrichum crossandrae

Alternaria leaf spot : Alternaria amaranthi var. crossandrae

Major pests: Root knot nematode and Aphids


Major diseases

Leaf spot

Wilt and stem rot

Bacterial blight

Major pests: Root knot nematode, Aphids

Alternaria leaf spot resistant marigold varieties:

‘Golden Guardian’ and ‘Doubloon.’


Kumar, S., Tomar, K. S., and Shakywar, R.C., 2012, Response of gerbera varieties against powdery mildew disease under polyhouse condition. HortFlora Research Spectrum, 1(3): 286-288.

Cantor Maria and Lenuta Chis, 2006, breeding of gerbera hybrida at the fruit research station Cluj. Buletin USAMV, ISSN 1454-2382.

Grzeszkiewicz, W.H. and Witaszek, W., 1994, Evaluating the suitability of 26 rose cultivars grown for cut flowers in heated plastic tunnel. Zeszyty Noukowe, Instytutu Sadownictwa i kwiaciarstwa w skienriewicach,, 1 : 85-94.

Dhooria, M. S., 1999, Two spotted spider mite, Tetranychus urticae a serious pest of roses in polyhouses and its control. J. Acarol., 14 (1&2) : 84-87.

Gahukar, R. T., 2003, Factors influencing thrips abundance and distribution on rose flowers in central India. J. Entomol. Res., 27 (4) : 271-279.

Hole, U. B. and Salunkhe, G. N., 2005, Studies on the relative resistance of rose cultivars to two spotted spider mite (Tetranychus urticae Koch.). J. Maharashtra Agril. Univ. 30 (3) : 316-317.

Dhananjaya Kumar K.S, 2007, Incidence and management of mites and thrips of rose under naturally ventilated polyhouse condition. M.Sc. Thesis, University of Agr icultural Sciences, Dharwad.

Krips OE, Willems PE, Gols R, Posthumus MA, Gort G, Dicke M.,2001, Comparison of cultivars of ornamental crop Gerbera jamesonii on production of spider mite-induced volatiles, and their attractiveness to the predator Phytoseiulus persimilis. J Chem Ecol. 27(7):1355-72.

Prima W. K. Hutabarat, 2012, Morris Arboretum Nursery Trial: A Study of Rose Care Treatment.

Onozaki, T., Ikeda, H., Yamaguchi, T., 1998. Effect of calcium nitrate addition to a-aminoisobutyric acid (AIB) on the prolongation of the vase life of cut carnation fowers. J. Jpn. Soc. Hort. Sci. 67, 198- 203.

Ben-Yephet, Y., M. Reuven, and D. Shtienberg. 1997. Complete resistance by carnation cultivars to Fusarium wilt induced by Fusarium oxysporum f sp. dianthi race 2. Plant Dis. 81:777"780

About Author / Additional Info:
Ph.D Scholar at Indian Agricultural Research Institute, New Delhi