Working Group Minutes / Archives / Soybean Rust Task Team / 24 July 2003
Minutes

Soybean Rust working group

meeting held on Thursday 24 July 2003 at 09h00 at Nampo Park, Bothaville



  1. Opening

    Dr McLaren, an ARC-GCI representative, opened the meeting with a prayer.

  2. Welcome

    The chairperson, Dr J Purchase extended a warm welcome to all present.

  3. Attendance and apologies

    Present

    Dr JL Purchase Grain South Africa (Chairperson)
    Dr J Dreyer ARC-Grain Crops Institute (observer)
    Dr NW McLaren ARC-Grain Crops Institute
    Mr AJ Pretorius ARC-Grain Crops Institute
    Dr AH McDonald ARC-Grain Crops Institute
    Dr AJ Liebenberg ARC-Grain Crops Institute
    Mr AJ de Lange ARC-Grain Crops Institute
    Mr GP de Beer ARC-Grain Crops Institute
    Mr KF Lawrance ARC-Grain Crops Institute
    Mr GJH Scholtemeijer Oil & Protein Seeds Development Trust
    Dr J de Kock Protein Research Foundation
    Mr L Killian Protein Research Foundation
    Mr NJ Vermaak Grain South Africa
    Mr AJ Cronje Grain South Africa
    Ms ED du Preez KwaZulu-Natal Department of Agriculture & Environmental Affairs
    Ms S Tweer KwaZulu-Natal Department of Agriculture & Environmental Affairs
    Mr ID Lamprecht Mpumalanga Department of Agriculture, Conservation and Environment
    Dr P Caldwell University of Natal
    Prof ZA Pretorius University of the Free State (Department of Plant Pathology)
    Dr FJ Kloppers PANNAR
    Mr A Jarvie PANNAR
    Ms M Govender PANNAR
    Mr LA Bester Monsanto SA
    Mr A de Klerk AVCASA (Du Pont)
    Mr NGE Hackland AVCASA (BASF)
    Ms P Kruger ARC-Grain Crops Institute (Secretary)

    Absent with apologies

    Mr FAS Potgieter Grain South Africa
    Mr N van Rij KwaZulu-Natal Department of Agriculture & Environmental Affairs
    Prof M Laing University of Natal
    Dr C Levy Commercial Farmers Union
    Mr A Bennett Monsanto SA

  4. Finalisation of agenda

    The agenda was approved, with the addition of points 7.5.3 and 8.1 to 8.3.

  5. Minutes

    1. Corrections and acceptance

      The minutes of the 3rd meeting of the Soybean Rust Task Team held on Thursday 25 July 2002, were accepted as a true reflection of the meeting with the following corrections being made:

      • Point 5.2.5 (page 4)
        "Dr Kloppers indicated that early plantings were used as indicator trials and that no specific indicator trials were conducted" should read "Dr Kloppers ... ".
      • Point 7.5.2 (page 6) paragraph 1 and 3
        The word AVCASA in paragraph 1, "Mr Scholtemeijer questioned the reduction in rates of Punch Xtra from the current emergency registration rate of 800 to 600 ml ha-1 as suggested by Mr De Klerk and the apparent contradictions of optimum rates and number of sprays between AVCASA, Cedara and Zimbabwean research results and asked for clarity on the point" and paragraph 3, "Dr Purchase commented that the single year trials done by AVCASA have been conducted for emergency registration" to be should read AVCASA Affiliated Companies because AVCASA as such does not conduct any research.
    2. Matters arising

      1. Literature study

        Dr Caldwell informed the meeting that a summary of available literature has been compiled and updates will be electronically distributed (see attachment 2).

        1. Literature Review by Ms Govender

          Dr Scholtemeijer indicated certain figures to be corrected, namely on page 4 and 28. "South Africa produces 208 000 tons of soybeans on 193 000 hectares" should be "131 000 hectares". He also mentioned that the Soybean Study Group of the Soybean Research Foundation had set a target of 150 000 hectares to be achieved in the planting season of 2005.

          Prof Pretorius informed the meeting that the order of the authors in the Review is not correct and that if the Review is to be used as a reference, it should be corrected and updated.

          Suggestion:

          The Review has a few noticeable mistakes and should be corrected. The meeting should read through the Review and any alterations / corrections / suggestions to be forwarded to Ms Govender and that a revised document be distributed to the Task Team again.

          Dr Kloppers

          Resolutions:

          The mentioned suggestion was accepted and seconded.

          Ms Govender's e-mail address will be distributed to the Task Team Members.

        2. Literature Review from Prof Pretorius

          Dr McLaren mentioned that it was minuted that Prof Pretorius had a draft Literature Study and that he was to assist with the editing. He enquired as to what became of the Literature Study?

          Prof Pretorius informed the meeting that no further work has been done on the Literature Study since it was written, but that it is available on request for working purposes.

          Resolutions:

          The Literature Study to be finalised and to be sent to the Secretariat.

          Prof Pretorius
          Dr McLaren

          Revised Literature Study to be distributed.

          Ms Kruger

          Comments / Discussions

          Mr Vermaak enquired about how the existence / availability of the Literature will be made known to outside organisations and also suggested that GSA's Website could be used.

          Dr Caldwell informed the meeting that the Literature Review originated because it is required by their academic programme that Honours students submit a Literature Review. At the time, literature was still being collected and the Review is not a comprehensive study. Ms Du Preez is currently busy with her Masters and will also be required to submit a Literature Review which will cover all the new / latest references. The reviews should be used as a building block and not be seen as a final document.

          Dr Purchase took note of Dr Caldwell's comment and mentioned that the feeling of the meeting is that the current Review be corrected / updated and together with the other Literature Studies be placed on the relevant Websites, i.e. GSA, ARC and the University of Natal and the Free State.

          Request:

          A deadline for the submission of Prof Pretorius' Literature Study.

          Mr Scholtemeijer

          Resolution:

          The Literature Study to be corrected / updated and to be distributed to the relevant institutions to be place onto their Websites at the end of 2003 / beginning 2004.

          Mr Scholtemeijer

      2. Pamphlets

        Dr Purchase indicated that the alterations as suggested / minuted have been done and that the revised pamphlet was distributed to all the relevant role players during February 2003.

        Mr Vermaak conveyed his gratitude towards the authors of the Literature Reviews and Studies. Although it appears that only criticism was provided, the hard work is recognised. He also mentioned that the pamphlet was very well received by the farming community and good feedback was received.

  6. Seasonal feedback

    1. Overview / general discussion

      1. Feedback from the researchers

        1. Mr Killian

          • Less rust was visible in Natal.
          • Rainfall was lower than normal.
          • He is of the opinion that the rust is the same / even more.
          • Trials at Cedara were planted a month earlier than last season and more rust was detected than the previous season.
          • Commercial farmers in the Winterton/Bergville area who planted later in December and did not spray, lost their entire harvest.
          • Farmers who planted short growing cultivars earlier in October and did not spray, escaped the rust.
          • Less rust was visible due to most farmers spraying preventatively.
        2. Dr McLaren

          • During the season because of the heat and the drought, the Piet Retief, Amsterdam area recorded no rust expect in some very late flowering plots.
          • One of the late plantings at Piet Retief was infected – the inoculum is still present.
          • Farmers should be made aware of the presence of the inoculum.
        3. Mr Jarvie

          • Two sets of trials containing 20 early and 20 late maturing varieties, were planted.
          • One set was planted early and the other late.
          • The early plantings (both varieties), showed no response to the fungicide sprays and escaped the rust.
          • The late plantings showed a 28% decrease in yield for the early maturing varieties and only a 12% decrease in the late maturing varieties - this finding is opposite to what was experienced last year.
          • The confounding factor is drought stress related and possibly the interaction between the rust and the drought stress.
        4. Ms Du Preez

          • Rust was detected at Cedara on 30 December and in the Karkloof area on 26 January.
          • Early signs were noticeable, but never developed to a severe stage until February.

          Dr Caldwell informed the meeting that they had an epidemic in their tunnels through natural infection and that the overhead irrigation might have provided the right conditions for the infection.

        5. Summary

          Rust was detected and identified in Winterton, Dundee, Vryheid, Piet Retief. Rust was not sighted in Ermelo and the Highveld, which means that it did not move up the escarpment.

        6. International development

          • The meeting is aware that Brazil had an epidemic during the previous season.
          • North America expected an epidemic to occur during the previous season, but it did not occur.

          Mr Scholtemeijer enquired as to whether the rust outbreak which was very severe in South America during the current season, is Pachyrhizi or whether it is something different. It is important to have confirmation, because if it is, we are moving on the same level as the Brazilians.

          Resolution:

          Task Team members attending the International Conference in Brazil to confirm whether Pachyrhizi was identified or not.

          Dr Caldwell

          Suggestion / Resolution:

          Information to be downloaded from the list-server "PROMED", that specialises on information on diseases and to be sent to the secretariat for further distribution.

          Ms Du Preez

          Dr Kloppers informed the meeting that an e-mail previously received, indicated and confirmed that the rust outbreak in Brazil was Pachyrhizi (see attachment 3).

          Mr Scholtemeijer expressed his concern that as a Task Team, the members are not fully informed and up to date as to what is happening in the outside world.

          Dr Purchase supported Mr Scholtemeijer's concern and emphasised that as researchers / specialists on soybean rust, information relating to soybean rust is to be obtained with more interest for future reference.

          The meeting pointed out that the disease has only just reached the western hemisphere and that no results are available.

          Request / Resolution:

          Members attending the International Conference in Brazil to draft a report on what is happening in South America and to sent it to the secretariat for further distribution.

          Dr Caldwell

          Mr Scholtemeijer requested that if Pachyrhizi has been confirmed in South America, as funders of soybean research they would like to know what the Americans are doing and how they are handling the situation. What can we learn from them?

          Dr Caldwell informed the meeting that the Americans have precautionary measures in place, seeing that they are not keen on using fungicides. Her feeling is that the Americans are looking to South Africa for guidance and advice since South Africa is used to spraying fungicides, has knowhow to do ratings and how to use the relevant equipment. South Africa is more advanced in soybean rust research than the Americans, seeing that they have not experienced it firsthand. Many countries are particularly interested in the environmental conditions and that the development of models will be the way forward.

          Dr Kloppers stated that it is unfair to expect the researchers to know everything, seeing that they only obtain information concerning this field of expertise. Information concerning other issues is available on various Websites and can be obtained.

          Suggestion:

          Dr Levy who is currently in Brazil, to be contacted and to be requested to draft and submit a report.

          Dr Purchase

          Mr De Klerk confirmed that, regarding chemical control, the Americans are in a worse position than South Africa, due to them not having registered chemicals.

          Mr Hackland agreed with Mr De Klerk and mentioned that one of the concerns is the lack of resistance strategy options in the American programme.

          Mr Scholtemeijer stated that his comment regarding the knowledge / information from other countries was misunderstood and that research has come a long way and that good work is being done, but emphasised that it is essential to learn as much from other countries as possible and that all resources need to be exploited. He also suggested a member to be sent abroad in order to evaluate the available information to date.

          Prof Pretorius informed the meeting that we have more knowledge and information regarding field work, chemical control and short term options, but that they have more knowledge regarding the molecular, genetic and fundamental characteristics.

          Resolution:

          Members attending the International Conference to draft a report and to submit the report to the secretariat three weeks after their return.

          Dr Caldwell

          Mr Jarvie mentioned that Ms Du Preez plans on going abroad and that funds are needed to sponsor the trip.

          Ms Du Preez confirmed that funds have been received, but not sufficient and mentioned that assistance with funding would be greatly appreciated.

  7. Report back and discussion of research projects

    (request electronic copies to be forwarded to Ms P Kruger at paula@igg2.agric.za)

    1. Fungicide trials – Ms ED du Preez

      See attachment 4.

      Comments / Questions / Answers

      Mr Jarvie commented that as is the case with Ms Du Preez's early plantings, he too had no reaction on his early plantings, while the later plantings showed a 28% decrease in yield. He also suggest that the planting dates might have an affect and that in future planting dates be replicated and also the length of exposure during the production period be researched.

      Ms Du Preez informed the meeting that Dr McLaren had four different planting dates, namely October, November, December and January. The October and November plantings had more rust than the December and January plantings and suggested that the disease is weather related rather than planting date dependent.

      Mr Killian commented that his trials planted during November were totally wiped out and mentioned that there is not enough unsprayed area in the trials for the inoculum to actually take hold.

      Dr McLaren informed the meeting that another aspect that needs to be investigated is spray-drift. His cultivar trial is situated next to a sprayed maize trial. The trial was not infected due to the spray-drift from the maize trial preventing infection.

    2. Soybean rust: risk analysis, loss assessment and quantification of the epidemiological value of in­ter­ven­tion technologies – Dr NW McLaren

      See attachment 5.

      Comments / Questions / Answers

      Dr McLaren stated that planting dates are related to weather and to try and relate rust to a specific planting date, is impossible. We need to concentrate more on the weather model and the risk of rust associated with the various weather conditions. He also mentioned that agronomic practices (planting widths, planting dates, etc.) have a minimal affect on the disease.

      Dr Purchase commented that Ms Du Preez also mentioned the importance of the weather model and that the weather interaction is obviously playing a bigger role than anticipated.

      Dr McLaren stated that it is more of a weather threshold because the disease can develop over a wide range of conditions. There is a threshold of moisture, leaf wetness, temperature, etc. below or above which the disease develops - the certain thresholds need to be researched.

      Dr De Kock requested comments on the possibility of Prof Seef Pretorius working on the role of host physiology.

      Dr McLaren informed the meeting of the possibility of working on biochemical reactions and that Prof Pretorius seemed very interested. He also indicated that the cost involved in the study, would roughly be R25 000. No definite proposal has been drafted or submitted.

      Dr De Kock requested more comments and information on the biochemical work, whether it is viable, can relevant information be obtained, is it a priority and if so, that a proposal be submitted to the Task Team for approval and the to the PRF for funding.

      Ms Du Preez informed the meeting that while reading literature for her Review, she has found papers published on biochemical work and offered to download and submit the information to Dr McLaren.

      Prof Pretorius mentioned that the University of the Free State has excellent plant physiologists already working on defense responses to biotic and abiotic stresses. He also stated that comparative experiments in the field and glasshouse will be needed to compare the different biochemical responses in the different environments and in order to do so, a huge amount of traveling is needed. He also offered to liaise between the task team and his colleagues if the meeting thought it necessary to submit a proposal.

      Dr McLaren mentioned that the idea is to link the biochemical project to the planting date trials and to use samples from the trials and link them to rust development at the various growth stages and specific biochemical changes.

      Dr Purchase asked whether work on biochemical reactions are of academic importance or whether it will make a definite contribution to the soybean industry and to the management of the disease?

      Prof Pretorius informed the meeting that it is more of an academic study, but that all resistance breeding work started with academic studies. We do not know the genes involved, how many genes there are, how they function, how they are expressed and how they are to be used in breeding and selection. If the actual mechanism can be determined, the information can theoretically be used for selecting better, more tolerant and resistant genotypes in future.

      Resolution:

      Host physiology and susceptibility needs to be researched - a project proposal on biochemical reactions to be submitted.

      Prof S Pretorius
      Dr McLaren

    3. Hypothesis statement for breeding for soybean rust resistance – Mr AJ de Lange

      See attachment 6.

      Questions / Answers / Comments


      Which germplasm is being referred to and was any of the material from America acceptable for continued use?

      The germplasm consists of 54 lines of which 17 are from AVRDC and the other 36 from America. No definite answers regarding resistance and tolerance from the American material has been obtained – the results and information available from Zimbabwe were used.

      Were the germplasm lines evaluated?

      The lines were planted right next to the cultivar trials and all were affected by the spray which means that the desired levels of rust infection were not achieved. The trial will be repeated, but the trial design and location will have to be replanned.

      It was minuted that Zimbabwean material showing sources of resistance will be followed up and Mr De Lange only referred to PI200466. Is that the only line that showed potential?

      Two lines from Zimbabwe were identified namely PI200466 and CM60, a selection from Chinmay, as resistance sources. CM60 could however not be obtained for further research purposes due to proprietary rights.

      Request:

      Germplasm not performing accordingly, to be reevaluated and to be artificially inoculated.

      Dr De Kock

      Dr McLaren commented that the inoculum is present, but that the locality needs to be changed and irrigation needs to be used.

      Resolution:


      • Germplasm trials to be repeated;

        Dr McLaren

      • possibility of other locations to be investigated;

        Mr De Lange

      • trials to be irrigated; and
      • suggestion of Prof Pretorius (planting of incolulated rows in-between) to improve disease development, to be used.

      Regarding line PI200466 having single gene resistance, what is the prognosis for the gene to remain effective in the future?

      According to the literature, the chances of the resistance breakdown is very good. Some altered lines and crosses from the 126 populations have proven to be more tolerant. It is important to find tolerance, but currently we do not have the necessary answers.

      Mr Jarvie commented that PANNAR is approaching the situation from a tolerance point of view rather than from a resistance point view.

      Regarding single gene resistance, has any work been done on the population diversity?

      Answer to be revealed in the presentation of Prof Pretorius.

    4. Epidemiology trials at UNP – Dr PM Caldwell

      See attachment 7.

      Comments / Questions / Answers


      Do we need to rate the disease as such or do we only need to look at the yield data at the end?

      Prof Pretorius explained that we first need data for the regression of disease against yield before making an assumption / decision regarding less emphasis on ratings can be made.

      Was the spore germination test done in the dew-chamber or was it just counting the spores at the different temperatures?

      It was based on Agar-plates, dew-chambers and incubators.

      University of Natal (UN) was doing research on overwintering host plant ranges - has any progress been made?

      They have not yet looked in the field for overwintering hosts. There are over 42 genera and over 90 species that it can overwinter on. They are currently looking for a Masters student to incorporate this study into his / her masters project. They want to start at Cedara with the soybean plots and to investigate the common weeds.

      Prof Pretorius informed the meeting that they have tried a once-off with pigeon peas as an overwintering host, but were unsuccessful.

    5. Feedback from other research trials

      1. Mr L Killian

        See attachment 8.

        Comments / Questions / Answers


        Why does a narrower row width have less disease? Is it a physical aspect of more leaves preventing inoculum penetration?

        No answer to the finding as yet.

        Mr Hackland commented that there is an interaction between the density of the crop at the point when the spores started falling and whether they got low enough into the canopy width. Closer spacing provided more of a canopy which prevented the spores from reaching the bottom leaves, meaning they took a longer time to develop.

        The differences between the cultivars are quite significant. How does this compare with the data from the previous season?

        During the previous season a number of cultivars, i.e. Carnia, Venda, Knap and Saan, had the same higher unsprayed yield values as this season. We have the data of two years to compare with the current year.

        Dr Purchase commented that the results confirm the results from the previous season. The results are significant and could have a significant effect on the farmer's selection of cultivar, yield and nett profit. Should the data not be used in the coming season for cultivar choice, characterising the varieties?

        Mr Killian feels that we need to reach the point where we can start advising the farmers to start using these cultivars.

        Mr Jarvie informed the meeting that he has found that not all the cultivars in his trials have reacted similarly to the last season. Last season they did a lot of initial indications based on differences in seed weight and this year on yield differences. It seems that the correlations is not what they would like. There were one or two varieties that acted similarly and indicated that he would be hesitant to state that after two seasons we have the answer.

        Resolutions:

        Both trials to be repeated during the coming season.

        Mr Killian

        Data / results from the three years to be used when publishing any information;

        Decision regarding the publishing of information regarding the differences of cultivars to tolerance, to be taken at the next meeting.

        Which cultivar is the most susceptible to increase the spores?

        Spitfire, but it is a long season cultivar. AS374 is a short season cultivar which is also highly susceptible.

      2. AVCASA

        1. BASF (Mr N Hackland)

          Trails were conducted over a wide area, but no infection other than in the Midlands. The triazole and triazole-strobilurin mixture was very successful. No significant differences between the dose rates or the different combination products were detected, but all were highly significantly different from the untreated control. The levels of infection in the untreated control were 15 to 20% due to the spray drift from surrounding treated plots. A big concern is that Amistar did not perform well. The approach to the disease is having a resistance management strategy in the programme rather than depending on a product which is known to be prone.

          Comments / Questions / Answers

          Ms Du Preez stated that Amistar treated plots showed high levels of disease. Comparing Amistar with Punch C, Punch C always outperformed Amistar. Amistar works better when used preventatively rather than cureratively.

        2. Du Pont (Mr A de Klerk)

          The work was limited to extra work done by Ms Du Preez – still awaiting the results. The technical advisor was contacted for information on emergency registration. The research done by BASF is new and not on chemicals for emergency registration. Information for emergency registration were to be submitted before July – companies still conducting research will probably receive extensions and those who haven't done anything, will loose their emergency registrations. Du Pont has still to submit the data from their second season which will result in converting the emergency registration to a permanent registration.

          Suggestion / Resolution:

          Representatives from Syngenta and Bayer to be placed onto the list of SBR Task Team members. Contact details of the nominated members to be submitted to the secretariat for correspondence.

          Mr De Klerk
          Ms Kruger

          Resolution:

          Information on currently available emergency registrations to be obtained from the Registrar and to be submitted to the secretariat to update the pamphlet.

          Dr Purchase
          Ms Kruger

        3. Syngenta

          Had one trial run conducted by Dr McLaren. Had low levels of infection – not much was learnt from the work done during the season.

        4. Bayer

          Couldn't be reached for comments.

      3. Prof ZA Pretorius

        See attachment 9.

        Comments / Questions / Answers

        Have the isolates been sent to Dr Frederick?

        The original was sent to him.

        Suggestion / Resolutions:

        Artificial infection in controlled environments and greenhouse screening are not providing enough information. It is important to investigate / research infection types within new varieties in South Africa.

        Consensus was reached that the mentioned suggestion / research be conducted. Lines / material to be provided to conduct the mentioned / suggested research.

        Prof Pretorius

        Since Dr Frederick indicated his concern about the current set of differentials, resolving the encountered problems needs to be coordinated. The SBR Task Team representative to convey the problems at the International Conference in Brazil.

        Dr Caldwell

        Has Dr Frederick done molecular work on the different isolates?

        Currently they have a very strong molecular programmes (virulence, variance, pathogenicity, etc.), seeing that they can't take the pathogens into the field.

        Dr Caldwell mentioned that Dr Levy is currently at Ford Dederick for three months learning their techniques.

        Suggestion / Resolutions:

        Isolates to be sent to Dr Frederick to be checked.

        Isolates can be sent but need to be purified and to be made into single spore isolates to be meaningful.

        Prof Pretorius

        What is the importance of physiological development?

        Suggestion / Request:

        Field trials on irrigated soybeans for physiological studies on rust to be conducted.

        Dr Caldwell

        Mr Killian informed the meeting that Dr Tattersfield once commented that whether a cultivar gets the rust early or late and how fast it develops on the cultivar, is related to how susceptible the cultivar is to the rust.

        Dr McLaren commented that what is missing, is the comparative epidemiology on the different cultivars and the develop­ment rates of the disease at various growth stages on the different cultivars. During the next season the disease progress curves of all the cultivars on a calender date scale and on a growth stage scale will be researched.

        Resolution:

        A proposal regarding soybeans under irrigation in to be forwarded.

        Any interested parties

  8. General

    1. Strategy for coming season

      1. Fungicide trials (Ms ED du Preez)

        Status : Continue

        Request:

        Certain trials be terminated and to only concentrate on specific trials to ensure better comparative results.

        Dr Caldwell

        Suggestions / Resolution:

        • Aerial application to be taken out;
        • Timing of adjuvants not highly prioritised and to be taken out;
        • Cutting down on number of treatments on efficacy trails;
        • Timing and frequency trials - continue spraying at flowering;
        • Number of sprays to be altered;
        • Irrigating at night to increase infection levels;
        • Investigate environmental conditions, i.e. relative humidity, leaf wetness, maximum temperatures, rainfall, etc.;
        • Modification of current research project:
          • Modify fungicide rates to a selected few fungicides in different chemical groups;
          • Modelling the disease occurrence to develop spray prediction advisories;
          • Develop an economic risk assessment on spraying of fungicides; and
        • Alterations to be submitted to Dr Caldwell, Prof Pretorius and McLaren for comments.

        Suggestion

        Continue to use the cultivar LS666. Don't want to complicate the data by starting a new reaction.

        Mr Jarvie

      2. Risk analysis, loss assessment and quantification of the epidemiological value of intervention technologies (Dr NW McLaren)

        Status : Continue

        Suggestions / Resolution:

        • Row width;
        • Concentrate on weather effects;
        • Cut back on row width and have more planting dates;
        • Physiological stages to come into play;
        • Put more effort into germplasm;
        • Piet Retief and Ermelo have cultivar trials and can serve as indicators; and
        • Coordinate projects with Mr Lawrance to prevent duplication of trials.
      3. Hypothesis statement for breeding for soybean rust resistance (Mr A de Lange)

        Status : Continue

        Suggestions / Resolution:

        • Winter plantings to be harvested;
        • Seed of populations to be divided - one part to be sprayed and to determine the reaction of two sprays on the same population;
        • F2 to be planted at Cedara for evaluation on further single plant selections;
        • Winter and selection programmes to continue;
        • Material for germplasm evaluation already harvested - processing of data in progress.
      4. Epidemiology trials at UNP (Dr P Caldwell)

        Status : Continue

        Suggestions / Resolution:

        • To continue with the project as is.
      5. Other research trials

        1. Mr L Killian

          Status : Continue

          Suggestions / Resolution:

          • Categorising according to maturity to stand-over until the next meeting;
          • Planting dates in managing rust is extremely important;
          • Planting from beginning of September with three week intervals through to middle January;
          • Plant three cultivars (short, medium and long season cultivars);
          • Treatments are to be unsprayed, sprayed at flowering and 21 days after flowering; and
          • Later plantings to shrink the time from flowering to physiological maturity – later plantings to be used to determine whether one spray will be sufficient or not.

          Suggestion / Resolution:

          • Row spacing to be incorporated into the planting times;
          • Planting dates can have an effect depending on the area, i.e. at the coast or inland; and
          • lanting dates and weather go hand in hand and a weather model should also be incorporated.

            A project proposal to be submitted to Dr Purchase, Dr McLaren, Mr and Prof Pretorius for peer reviewing. On approval, the proposal to be submitted to the PRF for funding.

    2. Control strategy

      See attachment 10, page 2.

      Resolutions:

      • Consensus was reached that the control strategy remain as it is;
      • wait another year for more comparative results / data to be gathered and processed; and
      • await / obtain comments from the private companies.
      Control Strategy
      Point 1 There is currently no other control strategy to follow, but to control the disease chemically with fungicides - to remain as it is.
      Point 2 Chemicals that have been granted emergency registration are Punch C, Punch Xtra, Capitan 250EW, Folicur 250EW, Bayfidan 250DC, Shavit 25EC, Alto 100SL and Score 250EC.
      Point 3 Preventative spraying is far more effective than curative spraying and, if possible, is recommended especially and more specifically for the areas where the disease occurred in the previous season. This should however be subject to the confirmed presence of the disease in the area.
      Point 4 Regular monitoring of indicator crops and frequent radio and other media reports will provide information on the spread of the disease at district, provincial and national level. In this way soybean producers can be forewarned in order not to spray unnecessarily, but in time to control the disease prophylactic.
      Point 5 Application rates and other relevant information is included in the label on the chemical containers and this should be read thoroughly and followed accordingly. Also consult reputable chemical companies and representatives for assistance.
      Point 6 No varieties with genetic resistance are currently available. A number of companies and institutions are involved in breeding for resistance, but varieties with resistance will only be available in a few years time.

      Contact names.
    3. Media strategy

      Dr Purchase reported that the detection of rust has been reported promptly as requested and agreed upon.

      Suggestion:

      • Reports on any information to be sent to Dr Purchase immediately, whereafter it will be sent to the secretariat for further distribution;

        Dr De Kock

      • Members visiting foreign countries to draft reports on what is happening and how it is handled; and
      • "PROMED" address to be distributed to the members for subscription.
  9. Future of task team

    The Task Team was initiated due to a crisis situation. The purpose of the Task Team is to report back on the season and how the disease generally progressed. The presentations and research projects are to monitor the development of the interaction between the pathogens and the hosts / environment and to develop an effective strategy to control the disease.

    Comments / Questions / Answers


    Has the objective of the Task Team been achieved?

    Suggestion / Resolution:

    Task Team to continue for at least two more years, whereafter a decision can be taken on whether the Task Team is to continue or to dissolve.

  10. Date of next meeting

    The next meeting has been scheduled for Thursday, 22 July 2004 at PANNAR, Greytown (Mr Jarvie and Dr Kloppers). Registration to start at 08:30 with the meeting starting at 09:00.

  11. Adjournment

    The meeting adjourned at 13:30 after the Chairperson thanked everyone for their active participation in the discussions.