Integrating morphological and molecular data sets of Mycosphaerella, with specific reference to species occurring on Musa

TY - CHAP

T1 - Integrating morphological and molecular data sets of Mycosphaerella, with specific reference to species occurring on Musa

AU - Crous, P.W.

AU - Groenewald, J.Z.

AU - Aptroot, A.

AU - Braun, U.

AU - Xavier, M.

AU - Carlier, J.

N1 - L. Jacome, P. Lepoivre, D. Marin, R. Ortiz, R. Romero & J.V. Escalant, eds.

PY - 2003

Y1 - 2003

N2 - The genus Mycosphaerella (= Sphaerella) is one of the largest genera of ascomycetes, containing more than 3000 named taxa. Approximately 23 anamorph genera have been linked to Mycosphaerella via cultural studies. Several of these anamorph genera have recently been reduced to synonymy based on phylogenetic studies derived from ITS1, 5.8S and ITS2 DNA sequence data. In addition, several genera not previously associated with Mycosphaerella, have also been shown to cluster within Mycosphaerella, which has proved to be largely monophyletic. From these results, as well as a re-evaluation of the criteria upon which anamorph genera are distinguished in this complex, a reduced set of informative criteria and genera are proposed.The degree of scar thickening, darkening and refraction, as well as the presence or absence of pigmentation in conidiophores and conidia appear to be useful features delimiting anamorph genera of Mycosphaerella. Species, however, are still separated on a combination of characters such as conidiomatal structure, the nature and arrangement of conidiophores, conidiogenesis, dehiscence scars and pigmentation. For the species that occur on Musa, anamorph morphology appears to be more informative than the more conserved teleomorph morphology, and can be used to separate the major pathogens, namely M. fijiensis (the causal agent of black leaf streak disease), M. musicola (the causal agent of Sigatoka disease), M. eumusae (the causal agent of eumusae leaf spot disease), as well as other reputedly less important pathogens.

AB - The genus Mycosphaerella (= Sphaerella) is one of the largest genera of ascomycetes, containing more than 3000 named taxa. Approximately 23 anamorph genera have been linked to Mycosphaerella via cultural studies. Several of these anamorph genera have recently been reduced to synonymy based on phylogenetic studies derived from ITS1, 5.8S and ITS2 DNA sequence data. In addition, several genera not previously associated with Mycosphaerella, have also been shown to cluster within Mycosphaerella, which has proved to be largely monophyletic. From these results, as well as a re-evaluation of the criteria upon which anamorph genera are distinguished in this complex, a reduced set of informative criteria and genera are proposed.The degree of scar thickening, darkening and refraction, as well as the presence or absence of pigmentation in conidiophores and conidia appear to be useful features delimiting anamorph genera of Mycosphaerella. Species, however, are still separated on a combination of characters such as conidiomatal structure, the nature and arrangement of conidiophores, conidiogenesis, dehiscence scars and pigmentation. For the species that occur on Musa, anamorph morphology appears to be more informative than the more conserved teleomorph morphology, and can be used to separate the major pathogens, namely M. fijiensis (the causal agent of black leaf streak disease), M. musicola (the causal agent of Sigatoka disease), M. eumusae (the causal agent of eumusae leaf spot disease), as well as other reputedly less important pathogens.

M3 - Contribution to conference proceedings

SN - 2-910810-57-7

SP - 43

EP - 57

BT - Mycosphaerella leaf spot diseases of bananas: present status and outlook

A2 - Jacome, Luis

A2 - Lepoivre, Philippe

A2 - Marin, Douglas

A2 - Romero, Ronald

A2 - Escalant, Jean-Vincent

ER -