Working Group Minutes / Archives / Soybean Rust Task Team / 14 August 2007
Minutes

Soybean Rust working group

meeting held on Tuesday 14 August 2007 at 09h00 at Cedara, KwaZulu-Natal



  1. Opening

    The Chairperson, Mr Scholtemeijer, opened the meeting with prayer.

  2. Welcome

    The Chairperson welcomed all present, with a special word of welcome to Mr Schalk Stapelberg and Mr Gerrit Odendal.

  3. Attendance and apologies

    Present

    Mr GJH Scholtemeijer OAC (Chairperson)
    Dr P Caldwell University of KwaZulu-Natal
    Dr J de Kock PRF
    Ms E du Preez PANNAR
    Dr BC Flett ARC-GCI
    Dr M Griessel PRF
    Mr A Jarvie PANNAR
    Mr ID Lamprecht Mpumalanga Department of Agriculture
    Dr AJ Liebenberg ARC-GCI
    Mr CJ Louw GSA
    Prof AH McDonald ARC-GCI
    Prof N McLaren University of the Free State
    Mr G Odendal Syngenta
    Mr FAS Potgieter PRF / GSA
    Mr W Roux Bayer Cropscience
    Mr S Stapelberg GSA
    Ms S Tweer PANNAR
    Mr NC van Rij KwaZulu-Natal Department of Agriculture
    Mr WF van Wyk PRF
    Ms E Harmse PRF: Secretariat

    Absent with apologies

    Mr AG Broeksma BAYER
    Dr M Craven ARC-GCI
    Prof ZA Pretorius University of the Free State
    Dr FJ Kloppers PANNAR
    Dr K Mashingaidze ARC-GCI

  4. Personalia

    The Chairperson thanked Mr Neil van Rij for attending to the arrangements of the meeting, and congratulated Dr Craven on the birth of her second child.

  5. Confirmation of agenda

    The agenda was accepted without additions.

  6. Approval of minutes – 25 July 2006

    The minutes of the 7th SBR Task Team Meeting held on 25 July 2006 were accepted as a true and fair reflection of the meeting.

  7. Matters arising

    1. Resistance to fungicides

      The Chairperson referred the meeting to the resolution taken at the previous meeting, on producers notifying Grain SA immediately if and when resistance to fungicides should occur, so that the chemical companies could be alerted. He asked whether any reports of resistance of soybean rust to fungicides had been received. The meeting noted that no such resistance had been reported.

      Resolution:

      1. That it be noted that no resistance of soybean rust to fungicides had been reported.

        Members

    2. Rust control

      The Chairperson reported that he had contacted chemical companies in order to establish whether legal action could be instituted against producers who did not apply fungicides in the prescribed manner. He said he had determined that no such action could be instituted, as producers could not be forced to spray. Prof McLaren said although producers could be held accountable in terms of Act 36 of 1947, should they not apply a chemical according to the registered rates, dosages, etc, this would be difficult to enforce. Mr Potgieter said that the matter would have to be resolved, as rust could present a problem of catastrophic proportions if not controlled by chemical spraying. He reported that producers were prosecuted a number of years ago for not ensuring that the mosaic virus was exterminated by neglecting to spray against the virus vector on self-sown tobacco during winter. Dr Liebenberg said that action could only be instituted if quarantine organisms were involved. Dr Flett was of the opinion that peer pressure would be the only means of ensuring that rust did not spread from farm to farm, and suggested that GrainSA could institute such an arrangement amongst its members, or within a study group. The Chairperson expressed his doubt that a producer would refuse to spray against rust after having planted soybeans with the view to making a profit. The members were in agreement that the matter be referred back to GrainSA.

      Resolution:

      1. That the matter of producers who neglected to control rust effectively, be referred back to GrainSA.

        Mr Louw

    3. Mr S Stapelberg: personal experience – a review of the past season

      The Chairperson called on Mr Stapelberg to inform the members on the extent to which soybean rust had affected his farming operations during the past season. Mr Stapelberg thanked the Chairperson for the opportunity. He reported that the area within an eighty kilometer radius of Piet Retief, which was situated in a mist belt and experienced high humidity, had traditionally produced one fifth of the country's soybean crop, but 12 000 tons only of soybeans were produced in the area during the previous season. He said that RoundupReady cultivars represented 90% of the soybean cultivated in the area, with 95% of the seed used being grain held back from previous season. He added that planting time was from the beginning of October to mid-December, with short growers planted as late as end December in the event of hail damage.

      Mr Stapelberg mentioned that the first occurrence of rust in the area was reported seven years ago. He said although rust had been controlled relatively effectively since the first occurrence, producers commenced with a system of preventative spraying two years ago. He reported that spraying was usually done at flowering stage, and was combined with the last spraying against bollworm, for reasons of economy. He added that it was more practical to spray preventatively, as it would not be feasible to start spraying only after rust was detected in an extensive farming operation, since much damage could already have been caused by the time spraying commenced. He said it had been found that there was a direct correlation between spraying and yield obtained, and that the cost incurred by spraying was negated by the improved yield. He reported that no rust was reported in the area during the present and previous season, although it had received higher than average levels of rainfall. He was of the opinion that rust could be controlled with relative ease, as opposed to sclerotinia, which had become a problem of major proportions in the Piet Retief area. He mentioned that producers were following a two years maize, one year soya crop rotation system as a result of the rust, and that he intended to decrease plant density to 250 000 plants per hectare.

      Mr Stapelberg closed his presentation by expressing his gratitude, on behalf of GrainSA and the country's producers, to the researchers who concerned themselves with such issues of importance to the farming community.

      The Chairperson invited questions from the floor. Mr Potgieter asked whether preventative spraying at time of flower was effected by means of a tractor, or by using a pivot-point. Mr Stapelberg said that tractors were used, and that damage caused by the tractors, even after time of flower, was minimal. In response to a question by Mr van Rij, Mr Stapelberg reported that Punch or Punch Extra was used for spraying against rust. He confirmed that he sprayed only once during a season against rust, added that timing was crucial and that spraying a full dose at time of flower was very effective. Dr Flett cautioned against making a hard and fast rule as the number of sprays was relative to the climate and epidemiology at the specific localities. He was of the opinion that losses per hectare may be worse in parts of KwaZulu-Natal. Prof McLaren indicated that longer growers could require more sprays than shorter growers. Ms du Preez said that certain chemicals could result in flower drop if sprayed at time of flower, and added that she had never seen rust appear before three weeks after the start of flowering in a normal growing situation. She said her recommendation to farmers had always been to spray as soon as the first pods were observed. Mr Stapelberg said producers found it to be more practical to spray at time of flower, or soon after flowering had commenced, rather than wait for three weeks, when rust could already have occurred. Ms du Preez mentioned that rust required at least eight hours of leaf wetness for infection.

      Dr de Kock recommended that Mr Henk van der Westhuizen of Philagro be approached with regard to the application of Sumisclex combined with a wetting agent to control sclerotinia by means of a pivot point, as Philagro had obtained very good results with this during the past season. He added that the registered dose of Sumisclex could be decreased if a wetting agent were added, and that use of a pivot point was crucial as one needed to soak the soil.

  8. Seasonal feedback

    1. Overview / General Discussion

      The Chairperson invited comments on the occurrence of rust during the past season. Mr Lamprecht reported that rust had not been reported in Mpumalanga. Mr Stapelberg was of the opinion that the occurrence of rust as well as that of sclerotinia was most probably hampered by the drought conditions experienced during the past season.

      The Chairperson reminded the members that reports had been received of rust having been detected on kudzu vine at Cedara on the 8th of January, on the soybean trap crop trials at Piet Retief on the 26th January, the trap crop trials at Greytown, at Martin Farm, Kadoma in Zimbabwe, on the soybean trap crop trials at Vryheid on the 1st of February, on the trap crop trial in the Morgenzon region, at Merrivale on the 12th of February, on the trap crop trials in the Normandien area on the 22nd of February, in Besters near Ladysmith and at Bergville early in March. The members agreed that this was a fair reflection of the occurrence of rust during the past season.

      Prof McLaren suggested leaving a border row at the edge of the field to determine what the conditions would have been if preventative spraying had not been effected. He mentioned that there was a difference between rust being present and rust being a problem. He said although rust occured at Cedara every year, it did not pose a problem every year. He said leaving a border row, or a row here and there, would enable one to determine whether or not problem levels of rust had been reached. Dr Flett said Dr Craven checked for the incidence of rust only, and did not endeavour to determine the severity of rust towards the end of the season, which could be what Prof McLaren had in mind. He said an unsprayed control would be required to determine the severity of infection, although he did not agree that a border should be used and thought that a block would be preferable. Prof Mclaren reported that widespread rust occurred in the Free State two years ago, but did not reach problem levels and did not cause damage. Dr de Kock supported Prof McLaren's suggestion that the amount of damage caused by rust be measured at the end of the season. Mr Jarvie agreed, and added that farmers needed to know whether or not spraying was worthwhile. He said spraying resulted in increased yield, even if no rust occurred.

      Prof McLaren disagreed with Dr Griessel's view that the information gleaned would be of academic value only, and said that soybean rust prediction models should possibly be refined, to make provision for high-risk and low-risk scenarios. Dr Caldwell agreed with Prof McLaren, but raised the question as to whether one could have definite certainty that rust would not become an epidemic during a particular season. Mr Potgieter said it would be dangerous not to spray, and Ms du Preez concurred, and raised the issue of using farmers as guinea pigs. She said the point of controlling rust was to keep the level of spores and inoculum to a minimum, and leaving blocks of unsprayed crops would increase the inoculum.

      Prof McLaren said if one could get some measure whereby loss could be linked to weather conditions rust could probably be managed. Mr van Rij said if the disease could be understood, it could be beaten. He said information on yield loss would enable one to determine whether or not rust was experienced as a problem. He said the industry could save a lot of money by not spraying needlessly. Mr Stapelberg asked whether a small block left unsprayed would give an indication of the same disease pressure that would have been experienced if no spraying had been done.

      Prof McLaren mentioned that any number of spores remained under the canopy after spraying, and added that rate and time factors, and not necessarily spores, are of crucial importance in the occurrence of polycyclic diseases like rust. The Chairperson suggested that Prof McLaren discuss the refinement of soybean rust prediction models to make provision for high- and low-risk probability of the occurrence of rust, and relating this to the need for preventative spraying, with the Technology Committee of the Protein Research Foundation (PRF).

      Resolution:

      1. That Prof McLaren discuss the refinement of soybean rust prediction models to make provision for high- and low-risk probability of the occurrence of rust, and relating this to the need for preventative spraying, with the Technology Committee of the Protein Research Foundation (PRF).

        Prof McLaren

  9. Report back and discussion of research projects

    1. An early warning system for soybean rust (trap cropping) – Ms M Craven

      The Chairperson said that Dr Craven had provided him with a report on the work done on the research project aimed at establishing an early warning system for soybean rust. He referred to the abstract of the report, in which Dr Craven stated that 'During the 2006/2007 season it was attempted to establish an early warning system for soybean rust. Ten localities were identified that represented major soybean production areas in the Free State, KwaZulu-Natal, Mpumalanga and Gauteng. Rust was first detected at the Greytown as well as Piet Retief sites on 26 January 2007. Since then rust was detected at Vryheid (1st February), Morgenzon (2nd February) and Normandien 22nd February). Kestell, Winterton, Kinross and Potchefstroom remained free from rust this season. The lack of rust reports in the majority of the trials included in this report could be attributed to a very dry and hot season'.

      Dr Flett reported on Dr Craven's behalf, and informed the meeting that Dr Craven had visited the various localities, had experienced a number of problems, and had offered some suggestions. He invited questions from the floor. Dr Flett said in response to a question from Dr de Kock, that he was not sure if Dr Craven had decreased the site size from 5 000 sq m to 500 sq m, but that she had indicated that site size varied, and depended on what the farmer had available. He said that in total 2 000 sq m were planted at each locality.

      Dr Griessel expressed concern that strict sanitary protocol was not followed by wearing the same pair of gumboots and overalls to all localities, even if these were sanitised with Jik after visiting a locality. He suggested that a pair of gumboots and an overall should be kept at each site, and not be removed from the premises. Mr van Rij mentioned that sites were visited in the order of clean to dirty. Dr Caldwell reminded the members that rust could travel across continents. Dr Flett said grey leaf spot was detected two seasons ago in areas where it had never occurred previously, and that it should be kept in mind that any epidemic was driven by an interaction. He said one should not lose sight of the bigger picture, as there were many interactions involved, which included climate, inoculum, and susceptible cultivars.

      Mr van Wyk mentioned that PAN421 and PAN520, the Pannar cultivars used in the trapcrop trials, were no longer on the market. Mr Jarvie said it had been decided to have an early variety and a late variety, so that a spread of maturity could be had, and that both cultivars would be RoundupReady, although he was not sure which specific cultivars would be used.

    2. Hypothesis statement for breeding for soybean rust resistance – Dr A Liebenberg

      See Annexure of the presentation for more detail.

      The Chairperson referred the meeting to item 9.2, the hypothesis statement for breeding for soybean rust resistance. He reported that Mr de Lange had left the employ of the ARC, and called on Dr Liebenberg to inform the meeting on the status of the soybean breeding programme.

      Dr Liebenberg gave a brief summary of the research undertaken during the past season, which included trials planted at both the rust-inducing and non-inducing soil types, the breeding as such, and the future of the breeding programme. He said that the past season had not been conducive to the occurrence of rust. He mentioned that rust came in late and that the trial planted in the non-inducing soil had a lesser degree of rust infection than the trial planted in the inducing soil. He reported that different generations viz. F4, F6 and F3 were planted in December, and that the pure F6 lines could not be evaluated for resistance as reliable observations were ruled out by the late occurrence of rust. With reference to the results, Dr Liebenberg reported that no selections had been made, but that all the lines were harvested, and enough seed for four rows would be retained in cool storage for future use. He said that the breeding programme was funded until March 2007, and officially terminated on that date, and that a progress and final report will be finalised by the end of September. He mentioned that a new project proposal would be compiled, should a new breeder be appointed.

      The Chairperson explained that a research project was usually funded for a maximum of four years in terms of the PRF funding policy, following which a final report was called for. He added that a new research proposal and an application for further funding could be presented if the researcher wished to carry on with the project.

      In response to a question by the Chairperson on the possibility of breeding rust-resistant lines, Dr Liebenberg indicated that Mr de Lange used single gene resistant material which was generally not considered to be sustainable. He said polygenic resistant material or horizontal resistance would be more desirable, and that there was a clear need for sources of resistance to be identified. Mr Jarvie mentioned that single gene resistant material was apparently available in Brazil.

      Dr Griessel said that the PRF became involved in the soybean rust programme well before rust presented itself as a problem in America and Brazil, and asked whether the involvement of larger institutions would not accelerate research progress. Dr Liebenberg remarked that adaptability to local conditions was important, and it would be a bonus if resistant cultivars with local adaptability could be imported. He was of the opinion that a local breeding programme was important with the view to sustainability. Mr Jarvie reminded the meeting that the soybean rust crisis was a thing of the past, as the disease could be controlled efficiently and effectively with a spray programme. He mentioned the possibility of his company getting involved, as terminating the breeding programme would mean that the money spent thus far had been wasted.


      ** The following discussion followed on the discussion of research project continuations, and is included in this section of the minutes as it relates to the soybean breeding programme.

      Dr Griessel mentioned that the breeding programme included rust resistance and nematode resistance, among others, and said that a breeding programme was slowed down by including too many selection criteria. He raised the possibility of transferring that aspect of the ARC's soybean breeding programme which focussed on rust resistance to Prof McLaren, as he was currently identifying cultivars and lines with increased tolerance to rust and had indicated that he intended sourcing cultivars from America. Prof McLaren said that his work supplemented the breeding programme, and could not replace such. The Chairperson stated that should it be possible to obtain cultivars from the Americas, then the question arose whether the local breeding programme should be continued.

      Dr Caldwell mentioned that the Brazilian government had invested an enormous amount of money in sending its top scientists all over the world, to obtain advanced degrees. She added that Brazil was now the top exporter of soybeans, livestock and meat, and was reaping the benefit of the money invested in its scientists. She thought this could relate to plant breeding as well, but questioned whether Brazilian lines would do well in South African conditions. Dr Flett cautioned against drawing parallels in this instance, and stated that one could not rely on international researchers to produce results for South Africa. He said this pertained particularly to breeding, as past experience had shown that international researchers were looking after their own interests, were competing in the world market, and were not likely hand out information of which they had not reaped the benefits in terms of the world market. He reiterated Dr Caldwell's statement on the intellectual and financial capacity which had been developed in Brazil over the last couple of years, with Argentina following close behind, and mentioned that an unbelievable number of Brazilian scientists were currently delivering international papers. He was of the opinion that a concerted effort was required from various sources to achieve the same in South Africa, and considered this to be a national priority.

      The Chairperson explained that the Foundation had decided to promote the soybean industry a number of years ago, and had, to his mind, made a reasonable job of it. He pointed out that the current shortage of local soybean breeders forced one to look elsewhere. He added that the ARC experienced manpower problems, and could not freely appoint the personnel required. He mentioned that he was due to meet with the president of the ARC, and would raise the issue with him, but that the alternatives had to be considered in the interim. Dr Flett suggested that the shortage of certain skills and knowledge could be addressed in terms of bursaries. Prof McLaren mentioned the possibility of collaboration with overseas institutes. Dr McDonald said there was much truth in what Dr Flett had said, and wagered the opinion that the major problem at present was the lack of a back-up system or succession planning. He said although it was important to draw on outside expertise, it would be preferable for South Africa to hold its own capacity in this regard, as the Brazilians, in his experience, tended to retain their best intellectual property as this enhanced their competitive advantage. He stressed the importance of South Africa not only having its own expertise, but also retaining this by means of proper succession planning.

      Resolution:

      1. That the issue of the lack of capacity in the soybean breeding programme be taken up with Dr Moephuli.

        Mr Scholtemeijer

    3. Epidemiology of soybean rust – Dr PM Caldwell

      Dr Caldwell reported that Ms Nunkumar's thesis had been examined and passed, and that she had been awarded an MSc degree. She added that a paper had been submitted to Plant Disease, but that one of the paper's referees had queried the leaf wetness duration in the dew chamber as this was based on an assumption. She reported that a student was developing a chart in order to determine the hours of leaf wetness obtained if a plant were to be placed in the dew chamber for a certain number of days at a specific temperature and humidity, and that the paper would be re-submitted once the leaf wetness-issue had been finalised. She said that the final budget and report on the project had been completed, and that a copy of the thesis had, to the best of her knowledge, been sent to the PRF, although she would check whether this had been done or not. The Chairperson asked that a copy of the article and an abstract of the thesis be provided to the members with the documentation of the following meeting.

      Resolution:

      1. That a copy of the paper on the epidemiology of soybean rust, as well as an abstract of Ms Nunkumar's MSc thesis be appended to the documentation of the next meeting of the Soybean Rust Working Group.

        Secretariat

    4. Use of silicon for the control of soybean rust on soybeans and other fungal pathogens on sunflower and groundnuts – Dr PM Caldwell

      Dr Caldwell reported that a PhD student would be starting field trials on soybean rust using silicon during September. She mentioned that interesting research was currently under way on the use of silicon, and that the University was hosting the Fourth International World Silicon Congress during 2008 with about 300 delegates expected to attend.

    5. Generating management-orientated maps of long-term soybean rust-susceptible areas for South Africa – Dr PM Caldwell
      (Item 9.5 of minutes)

      Dr Caldwell reported that the Masters student, who had been involved in the project, although it did not form part of his studies, had since completed his degree and taken up a position elsewhere. She said that she acted as co-supervisor on the project with the agrometeorological section, who had indicated that they would have a student available to work on the project from October.

      Dr Caldwell explained that it was planned to show areas with potential rust-susceptibility utilising historical weather data from the past ten decades. She added that she had sourced a formula to calculate leaf wetness from the ARC in Potchefstroom, and that the epidemiology work referred to previously would also be utilised in the mapping project, together with the ARC's information on areas with good potential for cultivating certain crops, and areas where diseases could break out.

    6. Determining the epidemiological value of resistance to rust caused by Phakopsora pachyrhizi in soybean lines – Prof N McLaren

      See Annexure of the presentation for more detail.

      Prof McLaren reported that he had tried to evaluate lines and cultivars for soybean rust during the past season. He said 30 cultivars and 266 lines were planted in three replicates, split over six weeks, to obtain weather differences and spread the risk. He explained that the idea had been to look at rust onset, the affected leaf area, infection rates, area under the disease-progress curve (audpc), maturity, defoliation and yield. He indicated that most of the cultivars and lines had already matured by the time rust came in, with the result that he did not consider the past season to be particularly successful.

      Prof McLaren said that previous data from cultivar evaluations had been written up for publication. He added that the aim was to do a component analysis, with the view to attaining horizontal resistance. He said there seemed to be a relatively small difference between the most susceptible and most resistant cultivars in terms of the rate of development, and that there were very low levels of partial or rate-reducing resistance, and that he intended to concentrate on this, to see whether significant differences could be found in the rates of development. He reported that a significant correlation had been found between yield and defoliation, and that the two extremes of the epidemic, the onset and defoliation, seemed to be the major criteria which could be identified at this stage. He added that the shorter growers tended to escape yield loss more readily that the longer growers.

      Prof McLaren concluded by saying that all cultivars were susceptible to rust, and that there were no cultivars at that stage with levels of resistance that were of economic value. He said the belief was held that progress could be made in terms of rust resistance should certain criteria be exploited and selected for, and that the intention was to replant the lines and evaluate as indicated. He also considered including some of the ARC lines. He reported that he would be attending a breeders' tour in Virginia in the United States in the near future, and intended to look for potential sources and look at establishing some form of collaboration with the Virginian breeders.

      In response to a question by Dr Flett, Prof McLaren explained that relative life time was calculated on days to maturity, and if maturity was 100 days during a specific season and rust came in after sixty days, relative life time would be 60%. He added that maturity date was based on a sprayed control. Dr Flett said that the implications of Prof McLaren's work was quite important, as the indications were that there was something to select for, and that some form of resistance, albeit incomplete, could be obtained, which would imply horizontal resistance. He added that this would impact on spraying programmes, and if the rate could be reduced to such an extent that the disease only came in much later, one might be able get away without spraying, or by reducing sprays, which would impact on the economics of the crop. He said it would be important to bear this in mind in future discussions on this topic.

      Dr Liebenberg said it was important from a breeder's point of view to have reliable selection criteria, that breeders were always looking for some method which could be applied to select for actual resistance, and that pathologists could be of assistance in this regard. He asked Prof McLaren to look into the possibility of providing some quick selection methods, especially with regard to horizontal resistance.

      Resolution:

      1. That Prof McLaren looks into the possibility of providing some quick methods which could be applied to select for actual resistance, especially with regard to horizontal resistance.

        Prof McLaren

    7. University of the Free State, Ms LC van Jaarsveld

      See Annexure of the presentation for more detail.

      The Chairperson asked Prof McLaren to comment on the artificial inoculation which according to indications would have been attempted during the field trial, and whether the plans to look at the structures of the pathogen rust spores that occurred before flowering compared to rust that occurred later, had actually transpired. Prof McLaren said that the artificial inoculation had, to the best of his knowledge, not been attempted. He said a distinction should be made between infection and colonization, and pointed out that although infection could be present earlier, colonization tended to occur after flowering. He mentioned that the hypothesis worked on was that some kind of physiological change took place which delayed the spread of rust on the plant prior to flowering.

      Prof McLaren reported that field trials were conducted at Kenilworth, the University's farm in Bloemfontein, and Cedara, from 2004 to 2007. He mentioned that some of the enzyme activities and carbohydrates were looked at. He reported that chitinase changed at different growth stages, and decreased at flowering stage, when the disease tended to take off. He indicated that chitinase seemingly played a role in the disease, but that this could not be quantified as yet. He said the same applied to the glucanases. He mentioned that there was an increase in peroxidase activity after infection took place during one season, but that this was not consistent as the same observation was not made during the following season. He said although there was an indication that some of the enzymes may be playing a role, they seemed to be greatly influenced by environment, and that the nature of the physiological changes was still unclear as no conclusive results had been obtained yet. He mentioned that this was the first research of its kind, and that a written report would be completed in the next few weeks.

      Mr Jarvie asked why different cultivars were used in different seasons. Prof McLaren replied that Stork had been used consistently throughout, but that the other cultivars were changed due to a shortage of seeds. Dr Flett remarked that he would have expected the interaction between enzymes and environment to be more consistent. Prof McLaren said epidemics had been plotted in previous reports, and added that no correlation could be determined between disease progress and enzyme curves. Dr Caldwell raised the possibility that soybeans flowered when the environment was conducive, and that flowering was not related to physiology. Prof McLaren said the intention was to separate the individual phenols with high performance liquid chromatography (HPLC), and determine what the phenols produced as a next step. This would be followed by a report and a proposal on the way ahead.

      Prof McLaren reported that the effect of plant nutrition on soybean rust was still being researched by Mr de Lange as part of his doctoral studies under Prof Sakkie Pretorius. He said that the greenhouse experiments had been initiated with the various nutrient levels, and the first run was being assessed. He said the treatments had been done hydroponically, using the variation in the levels of the nutrients that were found in the field trial, and attempting to relate the differences in nutrient levels in the field to the differences in rust infection.

    8. Feedback from other research trials

      1. Chemical Companies

        1. Du Pont

          No feedback had been received.

        2. Syngenta (Mr G Odendal)

          Mr Odendal reported that he had recently been transferred to Syngenta in KwaZulu-Natal, and that he intended to do research on soybean rust with products provided by Dr Gina Swart in Switzerland. He mentioned that other options were also in the pipeline.

        3. Bayer (Mr W Roux)

          Mr Roux said although chemicals were tested on an ongoing basis, there was nothing new to report on at that stage.

      2. Seed Companies

        1. Pannar – Mr A Jarvie

          Mr Jarvie informed the meeting that he did not have much to report on, as Pannar's rust work had been low key over the past season.

  10. General

    1. Strategy for coming season – various research projects

      1. Project Continuations

        • The use of silicon for the control of soybean rust, Dr PM Caldwell: project to be reported on the following year;
        • Generating management-orientated maps of long-term soybean rust-susceptible trends for South Africa, Dr PM Caldwell: project to be reported on the following year;
        • Determining the epidemiological value of resistance or tolerance to rust caused by Phakopsyra phakhyrhizi in soybean lines, Prof N McLaren: project to be reported on the following year;
        • The link between plant physiology and rust pathology in soybean, Ms LC van Jaarsveld: final report to be compiled and presented at next meeting;
        • An early warning system for soybean rust, Dr M Craven: to continue for a further two years. Problems were encountered in identifying producers with irrigation facilities. Problems had also been experienced because most of the producers were planting trap crops at the same time as commercial plantings, and spraying the whole block at flower, including the trap crop, which had effectively rendered the trap crop worthless. Trials had not been isolated from commercial plantings.

        Resolution:

        1. That with regard to the trapcropping project the localities, contributions of and lack of cooperation by collaborators to be discussed by Dr Craven, Dr McDonald and Dr Flett, and by the Technology Committee of the Protein Research Foundation.

          Drs Craven, Flett, McDonald
          Technology Committee
          Mr Keun

      2. Other research trials

        Mr van Rij reported that he was involved with other researchers in a remote sensing trial using satellite images to map the progression of soybean rust through a field.

      3. New research proposals

        None received.

    2. Control strategy

      1. SBR pamphlet 2006

        The Chairperson tabled the Soybean rust pamphlet, and asked whether the document needed to be revised. Ms du Preez said that the dosage rates were not indicated on the table, and suggested that the hazard classification be replaced by the ground dosage rates. Dr Griessel said this would not be advisable, as the chemical company may decide to amend the concentration levels. He added that people should be encouraged to read the labels on the bottles.

        Mr van Rij mentioned that the registration of the chemicals would have to be changed if the concentration levels were to be amended, and proposed that the dosage rates be included on the electronic version of the pamphlet, which was available on the PRF website. He added that Ms Tweer's contact details could also be amended on the electronic version. The Chair­person said this should be a reasonably simple exercise, and indicated that the possibility of effecting the suggested changes on the website would be investigated.

        Resolved:

        1. That the possibility of including the ground dosage rate for soybean rust control, and amending Ms Tweer's contact details on the electronic version of the 'Soybean rust pamphlet' on the PRF website, be investigated.

          Mr Keun
          Ms M du Preez

    3. Media strategy

      Status quo to be maintained.

  11. Additional matters

    1. Soybean Rust Working Group: the way forward

      The Chairperson informed the meeting that reports that rust had been detected were to be forwarded to the PRF, who would then distribute the information to those concerned.

      Ms du Preez suggested that the name of the Soybean Rust Task Team be changed to Soybean Rust Working Group, as 'task team' implied an emergency or crisis, and soybean rust was not considered to be a critical issue any more. The members were in agreement on this.

      Resolutions:

      1. That the name of the Soybean Rust Task Team be changed to Soybean Rust Working Group.

        Mr Keun

      2. That reports that rust has been detected be forwarded to the PRF.

        Members

  12. Date of next meeting

    The date of the next meeting was scheduled for Tuesday, 12 August 2008 at the University of KwaZulu-Natal at 08:30 for 09:00.

  13. Adjournment

    The meeting was adjourned at 13:00 after the Chairperson had thanked everyone for their active participation in the discussions.