BSPP News Spring 1998 - Online Edition

The Newsletter of the British Society for Plant Pathology
Number 32, Spring 1998

Reports of Recent Conferences

Plant Pathology - Global Perspectives of an Applied Science
1997 BSPP Presidential Meeting, York, December 1997

When family and friends enquire how I earn the daily crust, my stock answer is Plant Pathologist. After further elaboration they generally go away thinking of me as a plant doctor. And probably believing that I work in a laboratory akin to the local casualty, with worried farmers pacing the corridors nervously awaiting news of their prized potatoes. Any farmer reliant on my advice for the health of his potatoes would be well justified in looking nervous.

However, there is an important point here and it relates directly to the general thesis of the conference devised by our president, Nigel Hardwick. Plant Pathology is an applied science, at some point research findings should be put into a practical context. That requires pathologists to form messages and assist in making decisions relating to plant health whether at the field or international scale.

Nigel was the previous occupant of the office that I now use at High Mowthorpe. Whilst my career has focused mainly on the epidemiology of just two diseases, Nigel's first love is extension and his pathology interests have consequently been far broader. Yet by no stretch of the imagination do we represent the extremes of the Plant Pathology discipline. We can not turn back the clock to the days when extension pathology was generously resourced. So can the discipline accommodate the increasingly disparate interests and skills within its ranks and still remain a relevant and credible force in crop production? Nigel's presidential conference should provide some tangible evidence either way.

In keeping with the holiday spirit, the conference sessions were set out rather as a tour map for plant pathology. After some scene setting by Jim Waller, the President gave an interesting description of the changes in UK pathology during his distinguished career. We then proceeded from problem identification, onto diagnosis and risk assessment. A common theme of several talks was the need for better quantification of pathogen populations, and clear evidence of progress was provided. Too often epidemiological understanding has been held back by the poor quality of our measurements.

Day two began with disease forecasting. Bill Fry was honoured with giving the Garrett Memorial lecture. He treated the audience to a fascinating and lively talk about the vagaries of disease forecasting and its application to decision support. Also in this session Fen Beed provided evidence of some real progress towards improved understanding of disease:yield loss relations. This has been achieved through close collaboration between pathologists and plant physiologists. More evidence, if it was needed, that the boundaries of our discipline are being stretched ever further.

The cruel sport of the PH Gregory paper competition followed coffee. I have vivid memories of the torture inflicted on me by this experience. Even the most cynical could not fail to be impressed by the quality of the presentations this year. Alex Hilton fought off stiff opposition to take the prize for his work on resistance to fusarium ear blight in wheat.

In the afternoon the Central Science Laboratory played host to the conference. A friendly reception was provided by Nigel's colleagues who gave us the opportunity to see the breadth and quality of the work of the Plant Health group. Many of the delegates were clearly awe struck by the scale of the site and its facilities. For some this level of investment must sit rather incongruously with the present plight in research funding.

The opening session of day three concerned disease control This was an excellent showcase for the range of talents and skills contained within the society. John Mansfield detailed the new understanding of plant resistance mechanisms. Continuing the theme Phil Dale explained the science being applied to GMO crops. He provided a refreshingly frank appraisal of the potential benefits set against the ethical and technical challenges that are yet to be addressed satisfactorily. The value of more traditional epidemiological skills were also in evidence. David Yarham addressed the question of sanitation by the elegant combination of basic epidemiological models and anecdotal evidence from his career as a pathologist in ADAS. Andy Leadbeater rounded off the session with a discussion of the role of fungicides in disease management. Most pathologists have a grudging respect for the tenacity and success of plant pathogens. He therefore had little difficulty in convincing the audience of the need for integrated approaches to disease control.

In the final session the barriers to communicating research results to where they matter were addressed. Bill Clark described the proliferation of information, often contradictory, available to growers. Perhaps symptomatic of the reduction in extension pathology, we currently lack a coordinated framework for forming and transferring practicable messages. Technology transfer is not a trivial task and Bill left the audience in no doubt that we should not merely pay it lip service in the final section of grant proposals! David Brookes described a new decision support system (DESSAC) as a possible pioneer in transferring our hard won knowledge. Finally we were treated to a description of the Edinburgh Botanical gardens by our new president David Ingram. The audience were enthralled by his enthusiastic description of the work of this famous institution. In addition his vision of the future for BSPP and role of the International Congress in reflecting this provided a rousing and fitting end to our annual conference.

I went to the Christmas break heartened by the conference. Competition is an inevitable feature of research but so is collaboration; both add to the excitement. As a discipline we have avoided entrenchment into narrow and divisive interest groups. This is important because only as a truly integrated discipline will the full benefits of our work be realised. Extension pathology has not withered and died; instead it is evolving a new more dynamic structure that in the long-run will leave it better able to respond to the needs of industry.

At this point it is usual for the author to thank the BSPP for the generous bursary to attend the conference. I break with this tradition having received no such inducement. My task arose from under-estimating the formidable prowess of those two sports stars from Reading University, Mike Shaw and Jeff Peters. Mike took the Editor's request for this article in full flight and following a superb shimmy passed it on to Jeff. He, in one movement, produced a neat reverse pass that I caught in surprise. With nowhere to go I was inevitably caught in possession by a crunching tackle from James Brown!

Steven Parker, ADAS High Mowthorpe


Potato Pathology
One Day Offered Paper Conference, Edinburgh, Sept 1997

Continuing the successful format of one day meetings, BSPP held a joint meeting in September with the Scottish Mycology and Plant Pathology Club, on the subject of potatoes - a crop dear to many a Scottish pathologist's heart. The venue was Edinburgh and the delegate list saw a fairly equal spread of pathologists from Scotland, England, Ireland and Wales. The day was held in the newly built Michael Swann Building at Edinburgh University, where plush upholstery and thick carpets compensated to some extent for the fearsome array of gadgetry and controls that faced speakers on the platform. The programme had been put together by Mark Hocart, with the first session looking at blight and the afternoon encompassing everything from powdery scab to bacterial wilt.

Dr Jim Duncan of SCRI chaired the morning session, introducing it with birthday congratulations to the SMPPC which was celebrating 21 years since its first meeting. The Club, which was formed on a `temporary' basis has always provided an informal gathering of minds where questioning can often be intense but always constructive. Many students have come through the club and today it still has a good mix of members from post graduates to very active founder members. The joint meeting with the BSPP was an excellent coming of age party.

Stuart Carnegie from SASA gave the keynote speech, and reported on the links between disease transmission and tuber health - a wide ranging talk that put the rest of the day in context. Jenny Day of the University of Wales presented data on the population displacement of Phytophthora infestans in England and Wales which suggested that within commercial sites sexual recombination was extremely rare, but at non commercial sites, which tended to have more `unique' fingerprint isolates as well as more of the A2 type, sexual recombination could occur. Rachel Toth later presented a paper on the Scottish situation to complete the picture, concluding that the A2 type was also uncommon in the Scottish situation.

Ruairidh Bain (SAC) then talked about the possibilities of adjusting blight fungicide inputs in response to varietal resistance and concluded that it was possible to exploit the better resistance of some varieties by reducing fungicide inputs. Carrying on with the blight theme, Moray Smith of CSL presented a paper alarmingly entitled `Are Smith periods still relevant?' His conclusion was that they are, but with the proviso that they work because they fail less often and are therefore more prone to over-commitment than alternatives in crop weather systems.

Nigel Hardwick chaired the afternoon session where the pathogens discussed were many and varied. Rob Clayton (SAC) discussed the effects of condensation on disease development in stored crops and his work with small purpose built chambers has demonstrated that the infectivity and development of silver scurf increase as temperature and duration of condensation increase. A paper by Qu Xinshun of University College, Dublin, was presented by James Kavanagh and charted their ultimately successful quest to develop a PCR method for the detection of powdery scab in host tissues and soil. Paul Matthews of the University of Edinburgh then presented his work on the systemic nature of the blackleg pathogen and potential endophytic antagonists and concluded that the bacteria would move up within the plant from the site of inoculation but not downwards. He also demonstrated that Enterobacter could be a potential antagonist to Erwinia.

The final talk of the day was given by Prakash Pradhanang from Lumle Agricultural Research Centre, Nepal. He discussed different methods of detecting Ralstonia solanaceum in soils and concluded that of a semi-selective medium, a tomato bioassay, pre-enriched or normal ELISA methods or a PCR reaction, the semi-selective medium and the PCR reaction were the only two methods that successfully detected even very low concentrations of the bacteria. Practical reasons therefore meant that the semi-selective medium, SMSA, was often the preferred method of detection.

Many delegates lingered for a while over the posters or over afternoon tea which was taken on the upper floor of the building which offered panoramic views over Edinburgh and the surrounding hills. I am sure some looked up from the chatter to appreciate the sights, but as ever, the social side of such a meeting was almost, if not as important, as the academic side, and the sound of 80 or so plant pathologists after a good day was deafening!

Fiona Burnett, SAC Edinburgh


15th Long Ashton International Symposium
Understanding Pathosystems: a Focus on Septoria
Long Ashton Research Station, Bristol, September 1997

The symposium was organised by the Institute of Arable Crops Research, Long Ashton, and was supported by the British Society for Plant Pathology, Bayer PLC and the British Crop Protection Council. The meeting was attended by approximately 120 delegates, representing 14 countries. There was a total of 24 oral presentations and 33 posters, covering a diverse range of research on Septoria and Staganospora spp.

Professor John Lucas (IACR-Long Ashton) opened the Symposium, introducing, the first speaker Professor Zahir Eyal (Tel Aviv University), who gave a comprehensive overview of of Septoria and Staganospora and so set the scene for the meeting. There then followed two sessions which discussed the pathogens at the microscopic level. Prof Eyal took over as chairman for Session 1, "Genetics and Variation of the Pathogens", a very informative set of papers about the advances which have been made in the study of the two pathogens at the molecular level. In Session 2, "Host-Pathogen Interactions", the infection pathways of Septoria and Staganospora were examined, and a number of other pathogens were also considered as possible models for future work.

Dr David Royle was the chairman for Session 3, "Population Dynamics and Ecology", on the second day of the Symposium. In this session, the pathogens were discussed at the macroscopic level. Mr Tom Hunter (IACR-LARS) gave a particularly stimulating talk on the role of Mycosphaerella graminicola, the ascospore stage of Septoria tritici, in epidemics. Mr Hunter's work is helping to fill in some of the gaps in our understanding of the life cycle of this pathogen.

Session 4, "Disease Management and Decision Support", was the final session, chaired by Dr Nigel Hardwick (Central Science Laboratory). In this session, papers were presented on chemical control of the diseases and prediction of disease risk. It was especially enlightening to hear, from several speakers from agrochemical companies, how a new fungicidal chemical is discovered. This session also reminded us of the reason these diseases are so important by discussing the potential yield losses associated with them. The chairman commented, after Dr Vic Jordan (IACR-LARS) presented his paper, "thank-you, Vic, for bringing some reality to the proceedings".

Finally, a boat trip around Bristol harbour on the Tuesday evening helped us to get into the mood for the Symposium Dinner in the Glassboat Restaurant. Overall, this was a most enjoyable and stimulating symposium, with much interesting discussion. We would like to thank BSPP for the student bursaries which made it possible for us to attend the conference.

Sheila Nolan and Finian Bannon, University College, Dublin
Kirsty Howard and Jenny Rawson, University of Birmingham

 


Indian Phytopathological Society Golden Jubliee
International Conference on
Integrated Plant Disease Management for Sustainable Agriculture
New Delhi (India), November 1997

Opening of the conference

I attended this conference with the combined support of the British Society for Plant Pathology and the Indian Phytopathological Society. The meetings were held at the campus of the Indian Agricultural Research Institute (IARI). I acted as an official representative of the BSPP at the opening ceremony on 10th November, at which I was invited, along with other guests, to read a letter from our President to their President, congratulating them on achieving 50 successful years - as Nigel put it, from a teenage Society to their mature and venerable Society. The Golden Jubilee coincided with the Indian celebrations of 50 years of Independence from British Rule, but I believe it was coincidental that they did so.

The meeting was inaugurated by Professor M. S. Swaminathan, a colossus of Indian plant pathology and agriculture. He ranged widely over topics related to agriculture, and spoke much about the theme of the conference, sustainability, which is a matter of vital concern in the intensive agriculture practised in much of India. He described his work in developing a relatively low input and sustainable system of agriculture on a village scale in India. A critical test of such systems would be whether they could feed the ever-expanding population of India if widely practised. If you ever have the chance to hear this speaker, take it, as his broad experience and knowledge is presented in a stream of consciousness that is remarkable to hear.

The main scientific sessions were held from 11th to 15th November. The structure of the meetings was that, each day, there were two plenary lectures, one in the morning, the other in the afternoon after tea. The posters were to be viewed between lunch and tea time. After the plenary lectures in the mornings there were five parallel sessions, covering a very wide range of topics, including much virology, related no doubt to the chairman of the organising committee being Anupam Varma, head of the virology department at IARI. There were many sessions on integrated management of plant diseases, divided up into sessions for different crops, in which wheat and rice were important, but also including maize and millets, pulses, tuber and sugar crops, fibre and oilseed crops, vegetables, fruits and plantation crops, spices, medicinal crops and trees. These indicate the wide range of crops of importance in Indian agriculture. It was impossible to follow all these sessions and I found myself unadventurously rather confined to the wheat sessions, in which I tended to know many of the participants. There were more sub-divided sessions after the afternoon plenary lecture, so the days were very full, running from 09:00 to 20:00 daily but only until 17:00 on the Saturday.

Plenary lectures

The plenary lectures numbered nine, plus a valedictory lecture by R. S. Paroda, Secretary to the Department of Agriculture and Education of the Government of India, and Director General of the Indian Council of Agricultural Research, New Delhi. His topic was integrated disease management for sustainable agriculture and was a general review of the importance of diseases in Indian agriculture and methods of their control, in which resistant cultivars were mentioned at several points.

The plenary lectures were very interesting and some well-known scientists from other countries presented some excellent talks. These included R. J. Cook on `Ecologically-sustainable plant disease management', R. N. Beachy on `Pathogen-derived resistance to TMV in transgenic plants', A. Gibbs on `Viral evolution' and B. D. Harrison on `Whitefly-transmitted geminiviruses' which were among the most interesting. I particularly enjoyed the various papers on virus diseases. A. Gibbs gave a very interesting account of evolution of viruses, in which it seems that genome analysis indicates cross-linkages between different main groups of viruses so that surprisingly distant genetic exchanges have occurred in their evolution. This leads to a reticulated pattern, instead of the rather consistent evolutionary trees of higher organisms. Adrian Gibbs pointed out the risk of trying to classify viruses according to rules invented for such higher organisms. This information about evolution of viruses seemed relevant to information about geminiviruses, in which B. D. Harrison indicated that pathogen mediated resistance had not yet been successfully produced, and mentioned the risk of evolution of these viruses into new hosts. I developed a feeling that viruses of plants may have some unpleasant surprises in store for us, with possibly serious consequences. The theme of new diseases causing damage appeared in several papers, including examples given by A. Varma of new diseases of cowpea golden mosaic, okra leaf curl, and cotton leaf curl due to infection by geminiviruses already present in wild plants of India and resulting from the use of susceptible cultivars of the crops.

R. B. Singh, Director of IARI, gave a plenary lecture entitled `Breeding for durable resistance: global strategy and impact'. I wondered whether this should have been my title, but I do not think I would be able to estimate global impact or describe a global strategy for durable resistance breeding, as such. Although he did produce a slide with my definition of durable resistance on it, his talk was much more wide ranging, dealing with international aspects of breeding and the prospects for molecular breeding and genetic engineering. He also mentioned the prospects of Intellectual Property Rights and their potential negative effects on international co-operation. Other plenary lectures were given by J. C. Zadoks of Wagen-ingen, on models of epidemic spread of plant diseases, and J. P. Verma of IARI on control of bacterial blight of cotton, and lastly my own paper on the usual topic of identification of durable resistance and its exploitation in improving rust resistance in wheat.

An unusual feature of the plenary lectures was that they were treated as show-pieces, ending without questions (like BSPP Presidential Addresses) followed by presentation of a foot high brass statue of an Indian God, Natraj (a dancing manifestation of Siva I believe) with a brass plate inscribed with the lecturers name. Then the chairman of the session presented a eulogy of the lecturer and the lecture, giving a sort of precis of the lecture at the same time.

Wheat sessions

As noted above, I tended to visit the wheat sessions in the sub-divided groups. Here I met with many old friends from India and other countries and from CIMMYT . In the session for which I was chairman, with R. P. Singh as my co-chairman, some interesting results were described by Indian workers on the testing of wheat lines possessing the 1B-1R wheat-rye translocated chromosome. These lines automatically possess the genes Lr26, Yr9 and Sr31 for resistance to brown rust, yellow rust and black rust respectively. Of these genes, Sr31 has been suggested to have given durable resistance to black (stem) rust. When I visited Africa in 1993, infections of black rust on some wheats believed to carry 1B-1R was reported. A sample of an infected cultivar tested at the JIC (P. Martin) was shown to be heterogeneous for the presence of the translocated chromosome and infection could have been on plants lacking Sr31. At the conference in New Delhi, several lines with the 1B-1R chromosome were reported to have moderate to high infections with black rust in the south of India. As it did not seem likely that these could have been consistently observed if the infection was due to variable presence of Sr31, I suggested it would be important to test whether the infections were due to virulence for Sr31 or were due to environmental factors, such as high temperatures. The presence of the translocated chromosome in wheat cultivars and breeding programmes world-wide makes such a test of more than academic interest. It is somewhat surprising that this detail was not reported in the relevant abstract, in which is was suggested, without comment, that Sr31 was still effective.

I also gave a so-called keynote address in the session in which I was chairman. I believe I may have been the only visitor who presented both a plenary and a keynote lecture. This was not because of pushing myself forward, but because I was belatedly asked by the organisers to give the plenary lecture, probably when an unexpected slot appeared because of someone failing to attend. In my talk I described the remarkable spread of the wheat- and barley-attacking forms of the yellow rust pathogen, Puccinia striiformis in the last 20 years. Until 1975 the barley-attacking form (f. sp. hordei) was not present in the New World and infected landrace (criollo) cultivars in South America were always found to carry the wheat-attacking form (f. sp. tritici). The arrival of the f. sp. hordei in Columbia caused considerable epidemics on barley and it gradually spread northwards and southwards, reaching the north-western USA in 1993. The f. sp. tritici was found for the first time in Australia in 1979 and in New Zealand in 1980 and in 1996 for the first time in South Africa. The most likely agency for these invasions into new areas is travelling mankind. Perhaps what is surprising is how circumscribed the distribution of both these forms was until very recent times. The wheat-attacking form had been present for many years in the New World, and both forms in Europe probably from ancient times.

Keynote lecturers were also presented with a brass statue about 5 inches high, of an Indian Goddess (Saraswaty, representing learning) playing a stringed instrument, and again with a brass plate inscribed with the lecturer's name. This was not presented ceremonially, and questions to the speaker were permitted after keynote lectures.

Another topic of interest in the wheat programmes was the importance of Helminthosporium leaf blights in warmer areas of cultivation. These diseases, caused by various pathogens such as Bipolaris sorokiniana (spot blotch) and Dreschlera tritici-repentis (tan spot) are prevalent in Bangladesh, India and Nepal. In response to this problem, CIMMYT has placed its expert on these diseases, E. Duveiller, in Nepal, and the increasing prevalence of the diseases, particularly in the rice-wheat alternating crop system commonly practised, gives concern for the sustainability of this system. Declining yields have been recorded in some areas. To control these diseases, integrated management is necessary, using host resistance, good conditions for growth and balanced nutrition - not necessarily easily achieved where so many small-scale farms are involved.

Karnal bunt is another disease giving problems, both in the control of the disease in areas where it is endemic, and in effects it is having on international trade in wheat. The disease entered Mexico and then USA due to spread of infected wheats in nursery testing systems. Use of host resistance and hygienic seed are important means of control. The impact of the disease on preventing international transport of wheat is perhaps more damaging than the disease itself. I questioned one speaker as to whether the diseases would be confined to warmer climates, but the not reassuring answer I received was that the pathogen could survive frosty conditions.

Posters

There were many posters, displayed in a large marquee, many of them very well presented and attended by enthusiastic young Indian scientists who were eager to engage one's attention and to solicit views and advice from the audience. If you could not provide answers to questions on the spot, but suggested you would think about it, which I did, you would be pursued later for an answer. Despite the large number of participants, you could not hide in the crowd. Abstracts of most of the posters are given in the large book of abstracts provided at the conference. The posters covered a huge range of crops and a plethora of diseases - and inevitably, ranged from the level of identification of pathogens through to the molecular biology of hosts and pathogens. It is impossible to summarise them.

Programmes and book of abstracts

The organisers achieved production of several useful aids to conference participants, including a small fold-out leaflet with an overview of the programme, a pocket-sized booklet of more than 100 pages with details of the programme and speakers and a large book of abstracts for most of the lectures, session papers and posters, all very beautifully prepared and available at the conference. The abstracts book reveals the wide range of crops and pathogens being investigated in India.

Presentation of BSPP, the 1998 ICPP and CAB International

I carried with me to Delhi half a dozen samples of issues of Plant Pathology provided by Blackwells and BSPP posters and membership forms sent to me by Stuart Wale and Kevin O'Donnell. Peter Scott brought a heavy load including more posters for BSPP and for the Congress and excellent demonstrations of the CAB Crop Compendium. We commandeered two tables and boards near the entrance to the poster tent and set out our wares. The participants flocked round the tables like bees round a honey-pot (do bees really flock round honey-pots?). Within minutes of displaying six volumes (all different) of Plant Pathology, three had disappeared from under our very noses. Peter rapidly wrote `Demonstration Copy' in large black letters across the covers of the remaining three, which prolonged their presence somewhat, although by the fourth day, only one remained. More than 50 membership forms, and many application forms for attending the Congress in Edinburgh, were likewise snapped up. Many people displayed somewhat unwarranted optimism about obtaining funding to attend the Congress - but without out it, attendance at any meeting in the UK would be horribly expensive for Indians. I was most grateful to Peter Scott who not only presented his CAB material but also worked really hard on the presentation of BSPP, Plant Pathology and the Congress. I really feel I would have been lost without him.

Hospitality

Those of you who have visited India will know how hospitable Indians are, especially to foreign visitors. Can you imagine a BSPP meeting at which all your meals are provided by the organisers? All the participants received lunch and dinner provided from what would appear to us to be amazingly primitive kitchen equipment outside the marquee. The meals varied in style because there was a different caterer engaged for each day. Personal hospitality was provided to just about all the overseas speakers at the end of the conference, by Anupam Varma in his private house.

Oddments

All participants at the conference received a small statue of Natraj (about 6 inches high), inscribed with the title of the conference, thus bringing my personal total of statues to three, making quite a weighty metal trio. The visual aids for the conference were excellent, with reliable and skilful slide projection - a notable achievement at any conference.

I received a pleasing comment from a former member of the Plant Pathology Editorial Board, that, in his opinion, the current scientific standard of papers appearing in Plant Pathology is excellent. This contrasts with information I have received from UK sources that pathologists in some UK research establishments are ordered not to publish in journals with citation indices of less than 1, which includes Plant Pathology. A more arbitrary assessment of the standard and value of a journal it would be hard to imagine.

Acknowledgement

I am grateful to BSPP and to the Indian organisers for making possible my visit to India on this special celebration of the Indian Phytopathological Society. I enjoyed the meetings and also the chance to contact many old friends and to find some new ones.

Roy Johnson


Root and Butt Rots
9th International Conference, Carcans (France), Sept 1997

The conference was held at the holiday village of Carcans, near Bordeaux. With the conference information pack, the organisations gave us a gift: a field knife. The program for the meeting was divided into six different sessions:

1: Taxonomy, Genetics and Population Dynamics
2 : Etiology, Symptoms, Incidence and Epidemiology
3 : Ecology
4 : Pathogenicity and Resistance
5 : Modelling
6 : Control
We had in total 49 oral presentations and 55 posters.

Armillaria root rot is the most important disease affecting woody plants in gardens in the UK. Until recently it was usually regarded as one species, Armillaria mellea. Now it is accepted that it comprises several species. There are six different species of Armillaria in the UK and they differ markedly in pathogenicity. For us at the RHS it is important to distinguish them so we can give the appropriate advice to our members. We have been working on a PCR-based technique that allows us to identify the different species. I presented a poster on identification of Armillaria spp using a PCR method originally described by Harrington, T.C. & Wingfield, B.D. (1995).

The main themes of the conference were Heterobasidion annosum and Armillaria spp. It was important for me to see that in other countries Armillaria mellea, our major problem in the UK, it is either not a problem or it is absent. Instead, Armillaria ostoyae is the greater problem. Other themes were Fistulina hepatica on oak, decline of Austrocedrus chinensis in Patagonia (Argentina), Collybia fusipes on oak in France, stem decay of Eucalyptus nitens in Tasmania (Australia), the relationship between spruce beetle and Inonotus tomentosus in British Columbia and Rigidoporus lignosus.

RHS is also working on improvements to techniques for baiting Phytophthora from soil and infected plants. Although this fungus was not featured at the meeting, I met researchers who were interested in our work. There is also a possibility of future international collaboration on Phytophthora, in which the RHS should participate.

We had two field visits, the first one being a visit to Le Porge, an experimental plot of Pinus pinaster attacked by Armillaria ostoyae. From there we went to visit Lesparre-Medoc, a vineyard affected by Armillaria mellea. This visit gave us the opportunity to use the field knives and peel some roots, finding the infected ones. On the second field trip we visited the Forêt domaniale de Campet where Pinus pinaster was affected by Heterobasidion annosum, then in the afternoon, the Forêt domaniale de Montech, where we saw an experimental plot of Quercus rubra affected by Collybia fusipes. This fungus is causing oak decline in France. We have not seen this problem in the UK yet but now that we know the problem we will be alert.

The meeting was really intensive, having presentations in the morning and in the afternoon and a poster session in the evening, but it was very interesting to meet people who are working in the same field and gave me the opportunity to set up future work in collaboration with other institutions. I have new ideas from the meeting and I am looking forward to developing them. It has been a good experience and I look forward to attending future meetings. The next meeting will be in Quebec (Canada) in September 2001.

I would like to thank the British Society for Plant Pathology Travel Fund for financial support for my attendance at this meeting. It was a really interesting conference and gave me the opportunity to discuss our findings on Armillaria with other researchers.

Ana Pérez Sierra, Royal Horticultural Society, Wisley


5th European Fusarium seminar
Szeged (Hungary), September 1997.

The series of Fusarium seminars, begun in 1987 at Warsaw Agricultural University, concentrated initially on the problem of Fusarium in Europe, but have since expanded to become an international conference, encompassing all continents. The 5th European Fusarium Seminar was held in Szeged, Hungary, at the Cereal Research Institute and was attended by around 200 delegates from around the world.

Szeged, for those like us who are lacking in Hungarian geography, lies on Hungary's south-central border with Yugoslavia (about 2.5 hours by train from Budapest) and is noted for its salami (manufactured by Pick) and that most distinctive of Hungarian spices, paprika. Boy were we looking forward to meals! Both the welcome address and congress dinner (where for some bizarre reason the conversation at our table was dominated by that most "Royale" of sweets the lemon slice!) were held at the hotel Forras. Organised entertainment took the form of a most enjoyable evening concert in the holy Rókus church and an entertaining afternoon at the National Memorial Park at Ópusztaszer, where Prof. Dr Ákos Mesterhazy dazzled us with his knowledge of highlighted techniques currently in use that could be used to aid the taxonomist. It also introduced us to a comprehensive list of species which, as wheat pathologists, we are pleased to say we should never have need to identify.

The most interesting session to me, session 5, was entitled breeding for resistance, pathogenicity studies and ecological relations. The first part of the session focussed on plant breeding, with Sumai 3 being the major breeding source cited for resistance to Fusarium. The second part of the session dealt with the role of environmental factors, previous cropping and tillage in the spread of Fusarium species. Presentations related to ascospore release throughout the season and changes in disease profile due to the introduction of new crops were of particular interest.

Much was learned at a very informative and friendly Seminar. We would like to thank the organisers of the Seminar and those involved its smooth running for all their help. Thanks also to the British Society for Plant Pathology for their contribution towards the cost of the trip.

Philip Jennings, CSL, Sand Hutton
Helen Diamond, University College Dublin


Brassica 97
Rennes (France), September 1997

The Brassica 97 conference was jointly organised by the International Society for Horticultural Science (ISHS) symposium on Brassicas and the 10th Crucifer Genetic Workshop. The local organisers included the Institut national de la Recherche agronomique and Ecole nationale supérieure agronomique de Rennes This collaboration provided a wide range of topics for presentation and discussion, encouraging both oilseed rape and cole brassica scientists to attend. In all, over 350 people from 35 countries attended. The delegates came from a wide range of backgrounds including plant breeding, seed production, industrial research, academic research, genetics, agronomy and plant protection.

Rennes was a very appropriate place to hold the conference, as the principal town of Brittany, an area which produces 25% of France's vegetable crops. Brittany's northern coastal region is well suited to vegetable production as it has the advantage of mild winters without frosts and cool summer temperatures provided by the maritime climate. The area produces 40,000 hectares of brassica crops (mainly cauliflower and broccoli are exported) and a total of 70,000 ha of field cropping vegetables.

Many of the delegates at the conference were working with rapeseed (canola) and they provided some interesting new approaches to some of the presentations. My own interests in the conference lay in the control of clubroot. Before attending the conference I thought that clubroot (Plasmodiophora brassicae) must be a significant problem in areas where Canadian rapeseed is grown, considering the problem in other rapeseed growing countries. However it would seem that clubroot is not a problem for rapeseed production in Canada, although it severely affects cole brassicas in Eastern States.

Although only one paper was presented on clubroot other than that by my own supervisor, there were a number of posters on display at the conference which concerned clubroot. The paper on clubroot discussed the results of a screening programme which evaluated the resistance of certain crop varieties to P. brassicae, Alternaria spp. and Phoma. However, during the discussion following the presentation, it appeared that some of the varieties presented as resistant to P. brassicae have not been found to be resistant by other workers. This, therefore, again raises the need for identification techniques as to which race of P. brassicae is being used during resistance investigations.

A solution was provided to this problem by one of the poster presentations. The poster describes a new method for the characterisation of P. brassicae pathotypes by RAPD. This technique will allow a further decisive test to identify a certain pathotype race in addition to the European Differential Set which is currently used. The subject of clubroot control was also considered in several of the posters presented.

One interesting aspect of control in Chinese cabbage involved using daikon laphanus sativus) as a decoy plant for control of P. Brassicae. The cultivation of daikon prior to cabbage planting decreased the level of clubroot in areas were the resting spore load was not high. The work carried out in Japan and was suggested that the growing of daikon should be considered in a programme of integrated control.

Several groups working on clubroot are using Arabidopsis thalliana as a model plant system in order to study both resistance to clubroot and the effects of infection upon host metabolism. The projects involve the use of resistant mutants and a variety of molecular and microscopy techniques to investigate the infection process of P. brassicae. A Russian research team presented work being carried out in a breeding programme using resistance found in some local brassica varieties. The study is also examining pathogen strains, sources of resistance and resistance mechanisms along with the development of screening methods.

One of the most useful meetings was the clubroot working group. This allowed all people at the conference who were interested in clubroot to get together and find out about each other's work. From this session it was then possible to find people working in a similar area of work with whom it was possible to discuss ideas. During the remainder of the conference, and at the several receptions and meals it was possible to talk to most of the authors and discuss research ideas and areas of collaboration. In the case of my own research, I was able to realise that the work of several groups ran in a similar vein and that, certainly in the case of investigations into the invasion processes of P. brassicae and the environmental influences upon these processes, an exchange of ideas and theories would be beneficial to all groups.

With such a wide range of topics being presented at the conference along with the clubroot working group, it was possible to consider a number of new approaches towards my own project. It was interesting to hear from a number of plant breeders that clubroot is still a huge problem and that they themselves need to see more research being carried out into how the P.brassicae pathogen can be controlled before they will be able to restart breeding programmes for clubroot resistance on a large scale.

The problem with varieties resistant to P. brassicae is that the resistance used is vertical resistance. Due to the extremely plastic nature of the fungus this resistance is easily overcome. This means that until a more in depth understanding can be obtained into how resistance mechanisms operate
against the pathogen and possibly how nutrition can alter the success of the pathogen it is difficult to produce a long lasting resistance to P. brassicae.

The conference finished on a high note with the post symposium scientific tour to the Finistère vegetable cropping area. The tour involved a scientific and tourist tour of the scientific and technical organisations concerned with brassica production. The tour included an insight as to how Brittany had become such a successful vegetable production region through the introduction of co-operatives. At the conference hall of BBV, several presentations were given by the research institutes in the region about their work and research aims. The party could then either go on tour of the laboratories or the field trials. The latter were very interesting, consisting of cauliflower and broccoli trials along with trials on a crop of Romanescu cauliflower which I had not seen before. The afternoon was spent with a coach tour of the area with major institutes or major processing units being briefly visited.

The conference provided me with an ideal opportunity to meet not only people working in the same area of research, which was in itself valuable, but also people from other areas of research who were happy to discuss my own research and provide me with their own thoughts on the subject. The conference enabled me to make a number of useful contacts with other research groups and I am very grateful to the society for providing me with financial assistance so that it was possible for me to attend.

Lisa Page, University of Strathclyde