- The Origins and
History of the
- ISPP Committee on
Taxonomy of Plant Pathogenic Bacteria
- In the early 70s, I had
begun work with Doug Dye. Although my major research responsibilities were
not taxonomic I became engaged with the nomenclatural conundrum generated by
the development of the Code. The publication of the 1975 Code and the
criteria for inclusion in 1980 Approved Lists meant that most identified
plant pathogenic species, especially in Pseudomonas
and Xanthomonas, would cease to be
recognized for nomenclatural purposes. One response to this situation was to
ignore the requirement of the Code and to propose all names of plant
pathogens for inclusion in the Approved Lists, regardless of their
satisfying the intention of the Code. Such an approach, while serving the
utilitarian function of giving names to pathogens, would have subverted the
intention of the Code to serve the wider taxonomic purpose of providing
nomenclature that would reflect the natural relationships of bacteria. It
seemed to us that the only alternative such subversion was to generate a
system of nomenclature for pathogens at the infrasubspecific level that was
sufficiently robust that it would be accepted and used by the community of
bacterial pathologists. This would require a document analogous to the Code,
providing guidelines for naming plant pathogenic bacteria as infrasubspecies.
With Doug, I developed a proposal of the concept for publication (Young et
al., 1978a). In the extensive correspondence during this process it became
clear that there was little enthusiasm and some hostility to the concept, as
is still the case. We attempted to enlist most known bacterial pathologists
as co-authors, with little success. Final authorship comprised five
colleagues. Our paper was duly published and I gave a presentation at the 4th
International Conference on Plant Pathogenic Bacteria at Angers in 1978
(Young et al. 1978b).
- In parallel with these
activities, and as a response to the draft manuscript of our paper, Arthur
Kelman, as Chairman of the ISPP, convened an ad hoc meeting of interested scientists at Berkeley, in early 1978,
at which the issues were discussed. At this meeting, chaired by Milt Schroth,
the Committee on Taxonomy of Plant Pathogenic Bacteria of the ISPP was
founded. Its membership comprised J.F.
Bradbury, D.W. Dye, M. Goto, A.C. Hayward (Chairman), R.A. Lelliott and M.N.
Schroth. Minutes of these deliberations were published (Committee
on Taxonomy of Plant Pathogenic Bacteria of the ISPP 1978). At
the meeting, it was agreed that lists of names of bacterial pathogens would
be presented to the ICSP. These comprised names that met the criteria for
inclusion in Approved Lists and names that did not meet these criteria but
were important for plant pathologists. It was hoped that the ICSB would give
some recognition to the latter by acceptance of pathovars as an
infrasubspecific rank within the Code.
- In the event, the ICSB did not
agree although the
authors to the Approved Lists did acknowledge the danger of reuse of names
of plant pathogens in their introduction (Skerman et al., 1980). The CTPPB
then set itself the task of propounding in detail the International
Standards for Naming Pathovars (the Standards) under the aegis of the ISPP.
Doug as secretary steered the development of the Standards (and in fact
wrote them with the help of Rik Watson here), which were published as a
proposal (Dye et al. 1980).
- In the same way that
the Code gave no guidance as to methods or criteria for the differentiation
of taxa, the Standards gave little guidance either to methodology on
pathogenicity testing, nor did it, nor could it, formally specify in any
detailed way, what constituted a pathovar, by contrast with a race or
pathogenic strain. Pathovars were derived directly from previously named
species. This meant that they had relatively limited host ranges that were
defined in their descriptions, although as has become increasingly clear,
this did not necessarily mean restriction to related host plant taxa. It was
expected that a pathovar concept would evolve in a way similar to the way
the species concept has evolved. Our primary goal was to maintain continuity
of the existing nomenclature of plant pathogens, leaving open how
nomenclature would subsequently develop. It was obvious that many pathovars
could probably be established as species if relevant data was found. It was
equally obvious that it was highly unlikely that all pathogens would be
recognized as species.
- At this time, those
engaged in systematics were expected to develop their understanding of
formal nomenclature by reading the taxonomic literature, paying special
attention to the Code. The formation of the Standards occurred in this
climate. The community of
pathologists interested in taxonomy was very small. Development of a
taxonomic project was a major undertaking, not just an afternoon�s
sequencing, and those involved usually took the time to understand the
fundamentals of the discipline.
- The ISPP had no policy
of defining the activities of its Sub-Committees, nor, as far as I am aware
of any reporting policy. The CTPPB did take steps to give regulation to
itself. The 5th International Conference on Plant Pathogenic Bacteria was
held in Cali, Colombia, in 1981. Dye did not attend. At the Bacteriology
Section Meeting the organization of the CTPPB was discussed (Vidaver, 1982).
It was resolved that, in future, the Committee on Taxonomy would be the
responsibility of the Bacteriology Section Committee. Meetings would be held
under the auspices of the Section Committee at the regular international
conferences on plant pathogenic. Resignations from the CTPPB were to be
filled by consensus of the CTPPB or by the Section Committee. The Committee
elected was J.F. Bradbury, D.W. Dye (Chairman), R.S. Dickey, M. Goto, A.C.
Hayward and A.K. Vidaver.
- A public meeting of the
Committee was held at the ISPP Conference, Melbourne, 1983. Dye did not
attend and Anne Vidaver chaired the meeting. The
International Standards for Naming Pathovars (Dye et
al. 1980) were adopted by resolution of a meeting. I
was elected that the meeting. I have contacted Vidaver to see if there is a
record of business, without reply so far.
- The 6th International
Conference on Plant Pathogenic Bacteria was held in Maryland, in 1984. There
is no public record of the meeting. I do not know who initiated or chaired
this meeting. Neither Doug Dye nor I attended. The Committee after this
conference was J.F.
Bradbury, R.E. Davis, R.S. Dickey, G.L. Ercolani, A.C. Hayward, A.K.
Vidaver (Chair), J.M. Young. Following
this, I initiated the first revisions of the Standards and the development
of the first annotated list of names of pathogens. In this publication, the
Committee modified details of the Standards and provided a supplementary
list of names as an addendum to that of the 1980 paper (Young et al. 1991a).
- The 7th International
Conference on Plant Pathogenic Bacteria was held in Budapest, Hungary, in
1989. At that meeting, the elected committee comprised J.F. Bradbury, L.
Gardan, R.I. Gvozdyak, D.E. Stead, Y. Takikawa, and J.M. Young (Convener).
- The revisions to the
Standards were proposed at the Budapest meeting. The conference was held
immediately following the publication of Gabriel et al. (1989). Publication
of new species based on RFLP was disquieting as a precedent because of the
obvious taxonomic ambiguities inherent in the method. At this meeting, the
question of a discussion paper to caution against the use of RFLP as a
general method for proposing species was discussed. My correspondence with
R.G. E. Murray, then Editor of IJSB, brought
home to me the dangers inherent in our committee becoming engaged in
commentary on aspects of classification, whether of theory or of method. Our
Committee both makes and arbitrates the Standards. To engage in debate on
classification would almost inevitably result in becoming partisan and to
lose the claim to being an independent arbiter of nomenclature. The
publication of Young et al. (1991b), although by the membership of the CTPPB
was not in the name of the Committee. I confess that although I had
forgotten this distinction in recent discussions, I think it is very
important. I hope that when the Guidelines for the Committee are developed,
this point will be made explicit. My remark at the Edinburgh conference
should be forgotten.
- The 8th International
Conference on Plant Pathogenic Bacteria was held in Versailles, France, in
1992. The revision of the
Standards (Young et al. 1991) was
adopted by resolution of a meeting held at the ISPP Conference on Plant
Pathogenic Bacteria, Versailles, 1992. The committee elected was J.F. Bradbury, S.H. De Boer, L. Gardan, R.I.
Gvozdyak, G. Saddler, D.E. Stead, Y. Takikawa, L. Vauterin and J.M. Young
(Convener). At that meeting, Gerry Saddler proposed that the Committee
publish a full list of species and pathovars of plant pathogenic bacteria.
This was developed and published as Young et al. (1996).
- Until this time all
correspondence and manuscript development was in hard copy. Correspondence
turn-around was between 14 days and a month. At some point, the ISPP decided
that we were a Sub-committee under the Bacteriology Section and then that we
were a Subject Matter Committee, their President stating that we were one of
the more active subject matter committees.
- The 9th International
Conference on Plant Pathogenic Bacteria was held in Bangalore, India, in
1996. At that time, all N.Z. science positions were under threat and I did
not have travel funds. A meeting of the Committee was run (I think) by Solke,
Gerry and Louis Gardan, at which the taxonomic proposals of Vauterin et al.
(1995) on Xanthomonas were
discussed. (One of you would like to produce some retrospective minutes to
complete the record).
- The 10th International
Conference on Plant Pathogenic Bacteria was held in Charlottetown, Canada,
in 2000. The conference was held following the publication of Schaad et al.
(2000). The nomenclatural defects of this paper were canvassed and a
rebuttal was subsequently published in the name of the Committee (Young et
al. 2001). Following the discussion there, the ISPP was approached with a
view to activating a website, which was done.
- In 2001, as you know, I
became ill and Gerry Saddler agreed to be convener. I do not have any notes.
The Committee met at the ISPP Congress in Christchurch, New Zealand in 2002,
with Gerry in the chair. The main issue discussed was whether the committee
could act as an advocate for any particular nomenclature. I believe the
committee agreed that to advocate a particular nomenclature was to advocate
a particular classification, which was outside its scope. (In my view, the
neutrality of the committee can only be maintained by restricting itself to
noting the implications of adopting any particular nomenclature.) In 2003, I
became well again and Gerry and the committee agreed that I become convener
again. The List was updated and placed on the Website (Young et al. 2004.
- The 11th International
Conference on Plant Pathogenic Bacteria was held in Edinburgh, Scotland, in
2006. The rest you know.
2000, we gained access to the ISPP website and various documents were placed
on it. Since its inception, managing the information on the website has been
a source of constant frustration. The ISPP site was/is run through grace and
favour by CABI and had a low priority. Making changes to the site was slow,
sometimes impossible; changes agreed to were not made. It was almost a year
from the time that the updated List was submitted to its appearance on the
website. A general discussion site could not be got rid of. Very recently, I
discovered that there are separate entry points to our site and that
information available depended on the point of entry (Marion�s complaint
that she could not find the 2004 Lists was a mystery to me then out now
explained). At that stage there
was no obvious alternative for long-term management to the site. Recently,
the ISPP Executive agreed that we would have control of our web pages.
on the Web
- The 1996 List was
posted on the web in 2001. It contains all validly published pathogenic
species and all pathovars. As the introduction to the List explains, this
List contains all names of pathogens published since 1980, listed according
to the most recent publication, without commitment to any particular
taxonomic interpretation. It is not a �validation� list of species,
which is a matter for the ICSP, and in my view, it does not �validate�
pathovar names. All it can is point out which names do not conform to the
Standards, leaving it to others to decide which names they will use.
Annotations are made against species names where the Code may not have been
conformed with, and comment has been made where, in the opinion of the
Committee, the Standards have not been complied with. I proposed a number of
additional annotations, mainly connected with the publication of names in
which the descriptions do not allow differentiation of taxa except using
reassociation or sequencing methods. I did this so that pathologists would
not read description expecting to be enlightened about methods of
- At least as an interim
measure, the Committee prepared annual lists on new names. Each year, I
asked for names for the year and updated the lists of New Names. In
retrospect I wish I had produced a new list for each year. The question of
upgrading the 1996 lists whether by editing them on the web or of publishing
a further hard copy version, was in abeyance.
- This is an integrated
list comprising the above lists.
- 1980 D.W. Dye, J.F. Bradbury, M.
Goto, A.C. Hayward (Convener), R.A. Lelliott
and M.N Schroth.
- 1981 D.W. Dye (Convener),
J.F. Bradbury, M. Goto, A.C.
Hayward, R.A. Lelliott and M.N Schroth.
- 1983 J.F.
Bradbury, R. Davis, R.S. Dickey, M.
Goto, G.L. Ercolani,
A.C. Hayward, A.K.
Vidaver, (Convener), J.M. Young
- 1984 J.F. Bradbury, R.
Davis, R.S. Dickey, M. Goto,
G.L. Ercolani, A.C.
Vidaver (Convener), J.M. Young
- 1989 J.F. Bradbury, R.
Davis, R.S. Dickey, L. Gardan, R.I. Gvozdyak, G.L. Ercolani, A.C. Hayward,
A.K. Vidaver, (Convener), J.M. Young
- 1992 L. Gardan, R.I.
Gvozdyak, Y. Takikawa, G.E.
Stead, L. Vauterin, J.M. Young (Convener)
- 1996 L. Gardan, R.I.
Gvozdyak, L. Gardan, G.E.
Saddler, D.E. Stead,
Y. Takikawa, L. Vauterin, J.M. Young (Convener)
- 2000 C.T.
Bull, S.H. De Boer, G. Firrao, L. Gardan, G.E. Saddler, D.E. Stead and Y.
Takikawa, J.M. Young (Convener)
- 2006 C.T.
Bull, S.H. De Boer, T. Denny, M. Fischer-Le Saux, G. Firrao, G.E. Saddler,
D.E. M. Scortichini, Stead and Y. Takikawa, J.M. Young (Convener)
- 2006 C.T. Bull, (convener starting
August 2006). S.H. De Boer, T. Denny, M. Fischer-Le Saux, G. Firrao, G.E.
Saddler, D.E. M. Scortichini, Stead and Y. Takikawa, J.M. Young
2007 C.T. Bull (Convener). S.H. De Boer, T. Denny, M. Fischer-Le Saux, G.
Firrao, G.E. Saddler, M. Scortichini, D.E. Stead and Y. Takikawa
2013 C.T. Bull (Convener). T A Coutinho T. Denny, M. Fischer-Le Saux, G.
Firrao, Xiang (Sean) Li, G.E. Saddler, M. Scortichini, D.E. Stead, Y.
on Taxonomy of Plant Pathogenic Bacteria of the ISPP, 1978. I.S.P.P. Lists
of names of phytopathogenic bacteria in relation to the Approved Lists of
Bacterial Names 1980. Proceeding
of the 4th International Conference on Plant Pathogenic Bacteria � Angers, France, 1978, 395�399.
- Gabriel, D.W.;
Kingsley, M.T.; Hunter, J.E.; Gottwald, T. (1989) Reinstatement of Xanthomonas citri (ex Hasse) and X. phaseoli (ex Smith) to species and reclassification of all X.
campestris pv. citri strains. International
Journal of Systematic Bacteriology 39,
N.W.; Vidaver, A.K.; Lacy G.H.; Rudolph, K.; Jones, J. B. 2000. Evaluation
of proposed amended names of several pseudomonads and xanthomonads and
recommendations. Phytopathology 90,
- Vidaver, A.K.1982. General Meeting Report. Proceedings of the 5th
International Conference on Plant Pathogenic Bacteria � Cali, Colombia, 1981. 620-622.
- Young, J.M.;
Bradbury, J.F.; Davis, R.E.; Dickey, R.S.; Ercolani, G.L.; Hayward, A.C.;
Vidaver, A.K. 1991. Nomenclatural revisions of plant pathogenic bacteria and
list of names 1980�1988. Review of
Plant Pathology 70, 211�221.
J.M., Bradbury, J.F.; Gardan, L.; Gvozdyak, R.I.; Stead, D.E.; Takikawa, Y.;
Vidaver, A.K.; 1991. Comment on the reinstatement of Xanthomonas
phaseoli (ex Hasse 1915) Gabriel et
al. 1989 and X. phaseoli (ex
Smith 1897) Gabriel et al. 1989;
an indication of the need for Minimal Standards for the genus Xanthomonas. International
Journal of Systematic Bacteriology 41,
JM, Bull CT, De Boer SH, Firrao G, Gardan L, Saddler GE, Stead DE, Takikawa
Classification, nomenclature and plant pathogenic bacteria � a
clarification. Phytopathology 91, 617�620.
JM, Bull CT, De Boer SH, Firrao G, Gardan L, Saddler GE, Stead DE, Takikawa
Y, 2005. Names of plant pathogenic bacteria,
JM, Dye DW, Bradbury JF, Panagopoulos CG, Robbs CF, 1978a. A proposed
nomenclature and classification for plant pathogenic bacteria. New
Zealand Journal of Agricultural Research 21, 153�177.
JM, Dye DW, Bradbury JF, Panagopoulos CG, Robbs CF, 1978b. The use of the
term "pathovar" in the classification of plant pathogenic
bacteria. Proceeding of the 4th International Conference on Plant Pathogenic
Bacteria � Angers, France, 1978, 359�363.
J.M.; Saddler, G.; Takikawa, Y.; De Boer, S.H.; Vauterin, L.; Gardan, L.;
Gvozdyak, R.I.; Stead, D.E. (1996) Names of plant pathogenic bacteria
1864�1995. Review of Plant Pathology 75,
Carolee asked me about the use of the term
Convener rather than Chairman. In those gender sensitive days,
�Chairman� was out as sexist and I adopted the term �Chair� as
gender neutral, only to be reproached for making a term up. I chose
�Convener� as describing the function of the chairman to include the
meeting function and coordinator of committee activities in an inclusive