Monilinia Honey

Mycologia 20: 153. 1928.
  • Synonym: Monilia Bonord., Handb. Mykol.: 7. 1851.
  • Classification: Leotiomycetes, Leotiomycetidae, Helotiales, Sclerotiniaceae 
  • Type species: Monilinia fructicola (G. Winter) Honey. Holotype: BPI 1109031. 
  • DNA barcode (genus): ITS. 
  • DNA barcode (species): tef1.

Ascomata apothecial, cup- or funnel-shaped, long stipitate, pale brown, formed solitary or in groups from pseudosclerotia in aborted or mummified fruits and debris partially or totally buried in soil; stipe cylindrical, flexuous, pale brown, often darker near the base; hymenium comprising filiform, septate, unbranched and hyaline paraphyses. Asci unitunicate, inoperculate, with amyloid apical apparatus, cylindrical to clavate, flattened or rounded at the apex, thin-walled, 8-spored. Ascospores ellipsoid, often with tapered ends, 1-celled, hyaline, sometimes covered with a gelatinous sheet. Conidiophores single or aggregated forming sporodochia, straight or flexuous, hyaline to subhyaline, branched, thin-walled, septate. Macroconidia blastic-acropetal, oval, lemon-shaped or broadly ellipsoidal, rarely doliiform, hyaline to subhyaline, thin-and smooth-walled, 1-celled, sometimes presenting distinct axial connections (disjunctors), formed in chains, simple or dichotomously branched; microconidia (spermatia) sometimes present in old cultures, globose to pyriform, hyaline, smooth- and thin-walled, borne on lageniform, often asymmetric phialides. Arthric conidia occasionally formed, ovoid to ellipsoid, smooth- and thin-walled.

Culture characteristics:

Colonies on PDA white, yellow-grey, brown-grey or olive-grey, often zonate or forming concentric rings, felty to velvety, flat or concave, margin entire or lobed giving a rosette-like appearance, brown to black stromata can be present in old cultures.

Optimal media and cultivation conditions: PDA and WA, incubated under near-ultraviolet light (12 h light, 12 h dark) at 22–25 °C to determine growth rates, colour and shape of the colony, and induce sporulation of the asexual morph. The sexual morph is not formed under in vitro culture conditions but can be induced by inoculation on natural substrata and incubated several months partially buried in sterilised soil.

Distribution:

Worldwide.

Hosts:

Mostly found as crop pathogens or causing post-harvest losses on stone fruits, most commonly on members of Rosaceae, predominantly on Cydonia spp., Malus spp., Prunus spp. and Pyrus spp., but have been reported in at least 11 other genera on this family, linked to some kind of host specialisation. Other known hosts include members of Actinidiaceae, Berberidaceae, Betulaceae, Ebernaceae, Ericaceae, Euphorbiaceae, Moraceae, Myricaceae, Myrtaceae, Solanaceae and Vitaceae.

Disease symptoms:

Leaf spots, blossom and twig blight, twig and stem canker, fruit rot.

Notes:

Generic identification in vivo or in vitro is easy considering the characteristic monilioid hyphae and sexual-morphs. Monilinia is phylogenetically and morphologically related to the genus Sclerotinia, from which it can be differentiated by the absence of asexual reproduction and formation of true sclerotia in Sclerotinia. However, species identification in Monilinia is rather difficult by means of morphology alone. A combination of cultural features, physiology and host range is often necessary, including macro and micromorphology, growth rates, conidial dimension and characteristics of the germ tube during sporulation. Other employed techniques include AFLP and RFLP (Gril et al. 2010, Vasić et al. 2016), specific PCR amplification for the three major brown rot pathogens M. fructigena, M. fructicola and M. laxa (Cote et al. 2004, Gell et al. 2007) and amplification of specific introns for rapid identification of M. fructicola (Fulton & Brown 1997). A species delimitation based on molecular phylogeny is currently lacking and no ex-type material is known to exist for most taxa. However, several reference ITS and tef1 sequences are available from a set of curated isolates in Q-bank (http://www.q-bank.eu/Fungi/).

A proposal to protect the generic name Monilinia over Monilia has been recently published based on the complex and often conflicting taxonomic history of the latter name (Johnston et al. 2014). Following this proposal, two new combinations are proposed below.

References:
  • Batra 1988, 1991, Honey 1928, 1936, van Leeuwen et al. 2002 (morphology and pathogenicity); van Leeuwen 2000 (morphology, pathogenicity and epidemiology); OEPP/EPPO 2009, Martini & Mari 2014 (morphology, pathogenicity and biology).
  • Batra LR (1988). Monilinia gaylussaciae, a new species pathogenic on huckleberries (Gaylussacia) in North America. Mycologia 80: 653–659.
  • Batra LR (1991). World species of Monilinia (Fungi): their ecology, biosystematics and control. Mycologia Memoir 16: 1–246.
  • Cote MJ, Tardif MC, Meldrum AJ (2004). Identification of Monilinia fructigena, M. fructicola, M. laxa, and Monilia polystroma on inoculated and naturally infected fruit using multiplex PCR. Plant Disease 88: 1219–1225.
  • Fulton CE, Brown AE (1997). Use of SSU rDNA group-I intron to distinguish Monilinia fructicola from M. laxa and M. fructigena. FEMS Microbiology Letters 157: 307–312.
  • Gell I, Cubero J, Melgarejo P (2007). Two different PCR approaches for universal diagnosis of brown rot and identification of Monilinia spp. in stone fruit trees. Journal of Applied Microbiology 103: 2629–2637.
  • Gril T, Celar F, Javornik B, et al. (2010). Fluorescent AFLP fingerprinting of Monilinia fructicola. Journal of Plant Diseases and Protection 117: 168–172.
  • Honey EE (1928). The monilioid species of Sclerotinia. Mycologia 20: 127–157.
  • Honey EE (1936). North American species of Monilinia. I. Occurrence, grouping, and life-histories. American Journal of Botany 23: 100–106.
  • Johnston PR, Seifert KA, Stone JK, et al. (2014). Recommendations on generic names competing for use in Leotiomycetes (Ascomycota). IMA Fungus 5: 91–120.
  • Martini C, Mari M (2014). Monilinia fructicola, Monilinia laxa (Monilinia Rot, Brown Rot). In: Postharvest Decay, Control Strategies (Bautista-Banos S, ed). Academic Press, USA: 233–265.
  • OEPP/EPPO (2009). Monilinia fructicola PM 7/18 (2). Bulletin OEPP/EPPO Bulletin 39: 337–343.
  • Van Leeuwen GCM (2000). The brown rot fungi of fruit crops (Monilinia spp.), with special reference to Monilinia fructigena (Aderh. & Ruhl.) Honey. Ph.D. dissertation. Wageningen University, the Netherlands.
  • Van Leeuwen GCM, Baayen RP, Holb IJ, et al. (2002). Distinction of the Asiatic brown rot fungus Monilia polystroma sp. nov. from M. fructigena. Mycological Research 106: 444–451.
  • Vasić M, Duduk N, Vico I, et al. (2016). Comparative study of Monilinia fructigena and Monilia polystroma on morphological features, RFLP analysis, pathogenicity and histopathology. European Journal of Plant Pathology 144: 15–30.

Table 10. DNA barcodes of accepted Monilinia spp.

Species

Isolates1

Genbank accession number2

References

 

 

ITS

tef1

 

M. amelanchieris

ATCC 58538

Z73769

-

Holst-Jensen et al. (1997)

M. aucupariae

ARO 885.2

Z73771

-

Holst-Jensen et al. (1997)

M. azaleae

ATCC 58539

AB182266

-

Takahashi et al. (2005)

M. baccarum

CBS 388.93

KX982694

LT632532

Marin-Felix et al. (2017)

M. cassiopes

ARO 1459.S

Z73776

-

Holst-Jensen et al. (1997)

M. fructicola

CBS 329.35

KX982695

LT632533

Marin-Felix et al. (2017)

M. fructigena

CBS 348.72

KX982697

LT632535

Marin-Felix et al. (2017)

M. gaylussaciae

ATCC 64508

Z73782

-

Holst-Jensen et al. (1997)

M. jezoensis

4222T *

AB182265

-

Takahashi et al. (2005)

M. johnsonii

ATCC 58542

Z73783

-

Holst-Jensen et al. (1997)

M. kusanoi

NBRC 9725

00972502A

 

Harada et al. (2004)

M. laxa

CBS 132.21

KX982699

LT632537

Marin-Felix et al. (2017)

M. linhartiana

CBS 150.22

KX982701

LT632539

Marin-Felix et al. (2017)

M. megalospora

ARO 619.2

Z73788

-

Holst-Jensen et al. (1997)

M. mali

2769*

AB125619

-

Harada et al. (2004)

M. mespili

CBS 139.23

KX982702

LT632540

Marin-Felix et al. (2017)

M. mumeicola

3231 01-01*

AB125613

-

Harada et al. (2004)

M. oxycocci

ARO 1087.P

Z73789

-

Holst-Jensen et al. (1997)

M. padi

ARO 923.K

Z73791

-

Holst-Jensen et al. (1997)

M. polycodii

ATCC 58546

Z73792

-

Holst-Jensen et al. (1997)

M. polystroma

CBS102688T

KX982704

LT632542

Marin-Felix et al. (2017)

M. seaveri

CBS 170.24

KX982705

-

Marin-Felix et al. (2017)

M. ssiori

HHUF 19771T

AB220062

-

Harada et al. (2005)

M. urnula

ARO 476.1

Z73794

-

Holst-Jensen et al. (1997)

M. vaccinii-corymbosi

CBS 172.24

KX982706

LT632543

Marin-Felix et al. (2017)

M. yunnanensis

KY-1

HQ908788

-

Hu et al. (2011)

1ARO: Ascomycete Systematics Research Group, University of Oslo, Norway; ATCC: American Type Culture Collection, Virginia, USA; CBS: Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands; HHUF: Hirosaki University, Japan; KY: Strain code as stated in GenBank, * Hirosaki University Culture Collection, Japan. T indicates ex-type strain. A Accession number corresponding to the NITE Biological Resource Center, Japan.

2ITS: internal transcribed spacers and intervening 5.8S nrDNA; tef1: partial translation elongation factor 1-alpha gene.

  • Harada Y, Nakao S, Sasaki M, et al. (2004). Monilia mumecola, a new brown rot fungus on Prunus mume in Japan. Journal of General Plant Pathology 70: 297–307.
  • Harada Y, Sasaki M, Sasaki Y, et al. (2005). Monilinia ssiori sp. nov. in the Sclerotiniaceae, causing leaf blight and young fruit rot of Prunus ssiori in Japan. Mycoscience 46: 376–380.
  • Holst-Jensen A, Kohn LM, Jakobsen KS, et al. (1997). Molecular phylogeny and evolution of Monilinia (Sclerotiniaceae) based on coding and noncoding rDNA sequences. American Journal of Botany 84: 686–701.
  • Hu MJ, Cox KD, Schnabel G, et al. (2011). Monilinia species causing brown rot of peach in China. PloS ONE 6: 1–14.
  • Marin-Felix Y, Groenewald JZ, Cai, L, et al. (2017). Genera of phytopathogenic fungi: GOPHY 1. Studies in Mycology xxxx.
  • Takahashi Y, Ichihashi Y, Sano T, et al. (2005). Monilinia jezoensis sp. nov. in the Sclerotiniaceae, causing leaf blight and mummy fruit disease of Rhododendron kaempferi in Hokkaido, northern Japan. Mycoscience 46: 106–109.