Continuation Research Projects
Projects links
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Evaluation of commercially available sunflower cultivars
Cultivar trials from previous years showed that the mean yield of the five best cultivars is usually about 0.18 t ha-1 higher than the overall mean yield of all the tested cultivars. Considering that the national mean yield that farmers obtain is normally between 1.0 and 1.4 t ha-1, it is clear that cultivar selection has a significant effect on the profitability of sunflower production. This project is the only independent source of information on sunflower cultivar performance, available to producers. The aim of this project is to evaluate commercially available sunflower cultivars at different localities in collaboration with seed companies. During the 2019/20 season, 26 cultivars were evaluated in 21 successful locality trials. The highest trial mean yield of 3.52 t ha-1 was obtained at Kroonstad planted on the 17 January 2020 and the lowest of 0.89 t ha-1, at Potchefstroom with late planting date of 5 February. The six best performing cultivars, in terms of average yield calculated over localities, were PAN 7156 CLP, P 64 LL23, PAN 7080, AGSUN 5270, PAN 7160 CLP & PAN 7100. The overall mean yield for 2019/20 was 2.50 t ha-1, 12% higher than the mean yield of 2018/19. Eleven Clearfield and Clearfield plus cultivars were entered and one of these cultivars PAN 7156 CLP had the highest yields of 2.78 t ha-1 and performed the best in terms of seed yield. Eight of these cultivars namely, PAN 7156 CLP, PAN 7160 CLP, AGSUN 5103 CLP, AGSUN 5106 CLP, AGSUN 5102 CLP, PAN 7102 CLP, P 65 LP 54 and AGSUN 5101 CLP have yields higher than the overall mean yield of all cultivars. Seventeen cultivars were evaluated at 47 localities for the last three seasons and the cultivars, PAN 7156 CLP, PAN 7080, AGSUN 5270, PAN 7160 CLP and AGSUN 8251 had the highest yields. Probability to obtain an above average yield was calculated for all cultivars across the usual range of yield potentials. That was done for the 26 cultivars during the 2019/20 growing season, for the 22 cultivars that have been tested at 35 localities for the last two-seasons and for the 17 cultivars that have been tested at 47 localities for the last three seasons. The yield probability method is highly recommended for cultivar selection.
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Oilseeds South African Soybean Crop Quality Survey
During the harvesting of the 2018/2019 production season, which was the eighth annual soybean crop quality survey conducted by the SAGL, a representative sample of each delivery of soybeans at the various silos was taken according to the prescribed grading regulations. One hundred and fifty composite soybean samples, proportionally representing the different production regions, were analysed for different quality parameters. The samples were graded, milled and chemically analysed for moisture, protein, fat and ash content. Fifteen randomly selected samples were analysed to quantitatively determine the presence of genetically modified soybeans. Precision Oil Laboratories was subcontracted to perform fatty profile analyses on 20 composite crop samples representing the different production regions as well as 21 cultivar samples from different localities. These analyses were included to address the need for a national updated database for fatty acid composition of soybean oil.
The goal of this crop quality survey is to accumulate quality data on the commercial soybean crop on a national level. This valuable data reveal general tendencies, highlight quality differences in commercial soybeans produced in different local production regions and provide important information on the quality of commercial soybeans intended for export. With this data, SAGL is building up a database with quality data over different production seasons which can be used for decision making processes. The results are available on the SAGL website. The hard copy reports are distributed to all the Directly Affected Groups and interested parties. The report is also available on the website. The 2018/19 Report of the National Soybean Cultivar trials conducted by the ARC-Grain Crops Institute is also included in the report, as is the national grading regulations as published in the Government Gazette of 21 April 2017.
Summary of results
Eighty-nine percent (134) of the 150 samples analysed for the purpose of this survey were graded as Grade SB1, while 16 of the samples were downgraded to COSB (Class Other Soya Beans). During the previous two seasons, 13% (2017/18) and 12% (2016/17) of the samples were downgraded to COSB.
- One of the 16 samples was downgraded as a result of the presence of percentages foreign matter as well as collective deviations, exceeding the maximum permissible deviations of 5% and 7% respectively.
- Four of the samples were downgraded as a result of the percentage other grain present in the samples exceeding the maximum permissible deviation of 0.5%.
- Six samples were downgraded as a result of the percentage soiled soybeans present in the samples exceeding the maximum permissible deviation of 10%.
- Five samples in total were downgraded as a result of the presence of poisonous seeds. Four samples were downgraded due to the number of Datura sp. seeds exceeding the maximum permissible number (1 per 1000g) and the other one as a result of the number of Convolvulus sp. seeds exceeding 7 per 1000g.
Wet pods were not present in any of the 150 samples received and graded. The percentage samples containing sclerotia from the fungus Sclerotinia sclerotiorum, decreased from 59% (88 samples) in the previous season to 27% (41 samples) this season. The five highest percentages sclerotia observed ranged from 0.44% (sample from Gauteng) to 0.24% (samples from Mpumalanga and the Free State). These percentages are however still well below the maximum permissible level of 4%. The national weighted average percentage this season was 0.03% compared to the 0.06% of the previous season.
All fifteen samples tested for genetic modification (GM), tested positive for the presence of the CP4 EPSPS trait (Roundup Ready®).
The nutritional component analyses, namely crude protein, -fat, -fibre and ash are reported on a dry/moisture-free basis (db) for the current as well as the previous surveys. For comparison purposes the national 'as is' basis results were also calculated using the weighted national average values. As requested by the Research Priority Committee, both dry basis and 'as is' results are now included in the survey reports, refer to table below.
Comparison of weighted average nutritional component values on a dry and 'as is' basis over four seasons SEASON 2018/2019 2017/2018 2016/2017 2015/2016 Moisture, % (17hr, 103ºC) 7.0 7.4 7.4 7.4 MOISTURE BASIS DRY BASIS AS IS DRY BASIS AS IS DRY BASIS AS IS DRY BASIS AS IS Crude protein, % 40.43 37.60 40.18 37.40 40.15 37.20 40.22 37.22 Crude fat, % 19.1 17.8 19.3 18.0 19.8 18.5 19.4 17.9 Crude fibre, % 6.8 6.3 5.9 5.5 5.9 5.4 7.3 6.8 Ash, % 4.67 4.34 4.59 4.27 4.58 4.24 4.61 4.27 NUMBER OF SAMPLES 150 150 150 143 The graphs below provide comparisons between provinces for the nutritional
Average crude protein content over five seasons (2014/2015-2018/2019) 
Average crude fat content over five seasons (2014/2015-2018/2019) 
Average crude fibre content over five seasons (2014/2015-2018/2019) 
Average ash content over five seasons (2014/2015-2018/2019) 
Components Tested
The 2018/19 season is the first season that the SAGL conducted the moisture, crude protein and crude fat analyses on the ARC Grain Crops soybean cultivar trials' samples. Please see a comparison of the results between the crop survey and cultivar samples in the table below:
Comparison between the moisture, crude protein and crude fat results of the soybean crop
QUALITY AND ARC CULTIVAR SAMPLES OF THE 2018/19 SEASONAnalysis Moisture, % Crude Protein, % Crude Fat, % Crude Protein, % Crude Fat, % (17hr, 103ºC) (db) (db) (as is) (as is) SOYBEAN CROP QUALITY SURVEY RESULTS Ave 7.0 40.43 19.1 37.60 17.8 Min 6.0 35.43 16.5 33.13 15.3 Max 11.4 45.09 22.0 41.84 20.4 Stdev 0.67 1.30 1.24 1.20 1.16 N 150 150 150 150 150 ARC GRAINS CROPS CULTIVAR SAMPLE RESULTS Ave 8.0 40.54 20.5 37.32 18.9 Min 7.3 36.01 17.4 33.08 16.1 Max 8.5 46.05 23.8 42.24 21.9 Stdev 0.29 1.55 1.34 1.40 1.23 N 180 180 180 180 180 % Difference between crop and cultivar samples -1.0 -0.1 -1.4 0.3 -1.1 -
The funding of the Supply and Demand Estimates Committee
Introduction
It is important to note that the purpose of the monthly Supply and Demand Estimates Committee (S&DEC) meetings is to capture new information that is available in the market at a specific time. It is also crucial to understand that access to accurate market information plays a central role in any agricultural development and, to some extent, information can address other issues such as food security. In 2011, Grain South Africa applied for a statutory measure for grain traders to report information on export and import contracts. A similar approach is practised in the United States of America. The Grain SA application was opposed by other directly affected groups such as the South African Cereals and Oilseeds Trade Association (SACOTA); however, collaboration within SACOTA and the Supply and Demand Estimates Committee was subsequently established. The proposed statutory measure was then put on hold, and the committee sought to perform its activities without the interference of the statutory measure. The industry thus appointed Dr John Purchase as Chairperson of this committee, with the National Agricultural Marketing Council (NAMC) acting as secretariat. Following all industry engagements and consultations, the first official Supply and Demand Estimates report was published at the end of June 2013. The establishment of this committee was demand driven by the need to produce accurate and transparent market information to ensure that the market functions more efficiently for the participants.
Purpose of the South African Supply and Demand Estimates (SASDE) Report
The report provides an analysis of the fundamental conditions of the major grains and oilseeds in South Africa. The report is normally released within four to five working days after the Crop Estimates Committee (CEC) meeting. The report is released into the public domain by the approval of the South African competition authorities.
Composition of the S&DEC
The S&DEC is a technical committee that communicates directly with industry role-players through the Supply and Demand Estimates Liaison Committee (S&DELC). The S&DEC consists of a chairperson with two independent specialists appointed by the industry; the NAMC acts as the secretariat with four staff members, the South African Grain Information.
Service (SAGIS) and the secretariat of the CEC from the Department of Agriculture, Forestry and Fisheries (DAFF).
NAMC representatives
- Dr Christo Joubert – Manager: Agro Food Chains
- Ms Rika Verwey – Senior Economist
- Ms Lizette Mellet – Senior Economist: Statutory Measures
- Dr Abongile Balarane – Grain Specialist
DAFF representatives
- Ms Rona Beukes – Senior Statistician: Crop Estimates
- Ms Marda Scheepers – Senior Statistician: Crop Estimates
SAGIS representative
- Mr Nico Hawkins – CEO: SAGIS
Independent specialists
- Dr Andre Jooste
- Mr Peter Watt
- Dr Anton Lubbe
Methodology used by the S&DEC
Process before the meeting
- The S&DEC meeting takes place three to five working days after the CEC meeting, at the end of each month with the exclusion of December.
- A reminder is sent to all co-workers approximately seven days before the S&DEC meeting, requesting that they submit estimates on imports, exports and consumption for selected grains and oilseeds.
- The S&DEC meeting takes place in a lockdown room with no cell phones allowed, except when there is uncertainty about any of the figures sent by co-workers.
Factors that are taken into account during the meeting
- Supply figures
- CEC published figures
- S&D historical figures
- Demand figures
- Historical figures (SAGIS)
- Current deliveries published by SAGIS (extrapolations, regression modelling)
- Co-workers' figures, without disclosing their identity
- SAGIS figures
- Figures published by the CEC
- Figures and opinions of, and discussions with, co-workers
- Baseline modelling figures on demand and consumption from the Bureau for Food and Agricultural Policy (BFAP).
- Other modelling, including industry forecasting modelling and computable general equilibrium (CGE modelling), is also considered for use in the future, taking into consideration the expansion incapacity.
Distribution and users of the SASDE Report
The NAMC retrieves the number of website hits every month. The purpose of this exercise is to track the number of end-users of the SASDE report. It is noted from the NAMC monthly website hits that about 1000 hits are received for the SASDE report. The report is mainly utilised by the following:
- Academia
- Financial and investment institutions
- Government officials
- Grain Millers
- Oilseed processors
- Feed manufactures
- Grain and oilseed traders
- Grain and oilseed storage handlers
- Baking industry
- Research institutions and transport organisations
- Others
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Oilseeds South African sunflower crop quality survey
This was the seventh annual national sunflower crop quality survey performed by The Southern African Grain Laboratory NPC.
During the harvesting season, a representative sample of each delivery of sunflower seeds at the various silos was taken according to the prescribed grading regulations. The sampling procedure as well as a copy of the grading regulations form part of the report. One hundred and seventy-six composite sunflower samples, representing the different production regions, were analysed for quality. The samples were graded, milled, and chemically analysed for moisture, crude protein, crude fat, crude fibre as well as ash content. Precision Oil Laboratories was subcontracted to perform fatty profile analyses on 20 composite crop samples representing the different production regions as well as 20 cultivar samples from different localities. These analyses were included to address the need for a national updated database for fatty acid composition of sunflower oil.
The goal of this crop quality survey is the compilation of a detailed database, accumulating quality data collected over several seasons on the commercial national sunflower crop, which is essential in assisting with decision making processes. The results are available on the SAGL website. The hard copy reports are distributed to Directly Affected Groups and interested parties. The report is also available on the website.
In addition to the quality information, production figures (obtained from the Crop Estimates Committee (CEC)) relating to hectares planted, tons produced, and yields obtained on a national as well as provincial basis, over an eleven-season period, are provided in this report. SAGIS (South African Grain Information Service) supply and demand information, including import and export figures over several seasons are provided in table and graph format.
The report of the Evaluation of sunflower cultivars 2018/19 season conducted by the ARC-Grain Crops Institute in collaboration with Agricol, Pannar, Pioneer, Syngenta, Sensako and Link Seed is also included in this report, as is the national grading regulations as published in the Government Gazette No. 45 of 22 January 2016.
Summary of results
Seventy-six percent (133) of the 176 samples analysed for the purpose of this survey were graded as Grade FH1, with 43 of the samples downgraded to COSF (Class Other Sunflower Seed). The percentage of FH1 samples decreased compared to the 81% of the previous season. In the 2016/17 season, this percentage was 85%.
- Twenty-one of the samples were downgraded as a result of the percentage of either the screenings or the collective deviations or a combination of both exceeding the maximum permissible deviations of 4% and 6% respectively.
- Four samples were downgraded as a result of both the presence of sclerotia produced by the fungus Sclerotinia sclerotiorum and the collective deviations exceeding the maximum permissible deviations, namely 4% and 6% respectively.
- Four samples were downgraded as a result of the presence of poisonous seeds (Datura spp.) exceeding the maximum permissible number, namely 1 per 1000g.
- Three samples were downgraded due to the presence of a musty odour.
- The remaining eleven samples were downgraded as a result of a combination of one or more of the following deviations exceeding the maximum permissible deviation: percentage screenings, percentage foreign matter, percentage collective deviations as well as the presence of poisonous seeds (Datura spp.) or an undesired odour.
Gauteng province (3 samples) reported the highest weighted average percentage screenings namely 4.13%, followed by North West (N = 58) and Mpumalanga (N = 8) provinces both with 2.62%. Limpopo (12 samples) reported the lowest average percentage screenings of 1.47%. The weighted national average was 2.21% compared to the 1.91% of the previous season.
The highest weighted average percentage foreign matter (1.36%) was reported on the 95 samples from the Free State. North West followed closely with an average of 1.34%. The lowest percentages were found in Mpumalanga and Limpopo with 0.85% and 0.71% respectively. The South African average was 1.28% compared to the 1.16% and 1.06% of the previous two seasons.
The number of samples received for this survey that contained sclerotia from the fungus Sclerotinia sclerotiorum, increased from 78 samples (44%) in the previous season, to 90 samples (51%) this season. Sixty-one of these samples originated in the Free State province, 25 in North West and two each in Mpumalanga and Gauteng. Four of these samples (one from North West, two from the Free State and one from Mpumalanga) exceeded the maximum permissible deviation of 4%. Weighted average levels ranged from 0% in Limpopo to 0.98% in Mpumalanga. The Free State's weighted average was 0.49%. The national average of 0.43%, is the second highest since the 0.53% of the 2013/14 season. Last season's average was 0.17%.
The nutritional component analyses, namely crude protein, -fat, -fibre and ash are reported as % (g/100g) on an 'as received' or 'as is' basis. The graphs provide comparisons between provinces for the nutritional components tested.
Average crude protein content 'as is' (2014/2015-2018/2019) 
Average crude fat content 'as is' (2014/2015-2018/2019) 
Average crude ash content 'as is' (2014/2015-2018/2019) 
Average crude fibre content 'as is' (2014/2015-2018/2019) 
The SAGL conducted the moisture, crude protein and crude fat analyses on the ARC Grain Crops sunflower cultivar trials' samples. Please see a comparison of the results between the crop survey and cultivar samples in the table below:
Comparison between the moisture, crude protein and crude fat results of the sunflower Analysis Moisture, % Crude Protein, % Crude Fat, % (17 hr, 103ºC) (db) (db) SOYBEAN CROP QUALITY SURVEY RESULTS Average 4.7 16.40 37.9 Minimum 2.9 12.41 28.5 Maximum 7.7 20.02 45.2 Stdev 0.60 1.49 2.51 N 176 176 176 ARC GRAINS CROPS CULTIVAR SAMPLE RESULTS Average 4.8 16.44 43.6 Minimum 3.0 10.10 34.4 Maximum 6.0 25.37 55.4 Stdev 0.63 3.65 4.49 N 144 144 144 % Difference between crop and cultivar samples -0.1 0.0 -5.7 -
The role of seedling diseases in poor establishment of sunflower in South Africa
Poor establishment has been identified as one of the important constraints in sunflower production in South Africa. Although the contribution of other factors such as seedling vigour, seedbed preparation and soil temperature to poor establishment have been investigated, there is no information on the role of seedling diseases as a production constraint in sunflower production in South Africa. The main aim of this study is to determine the incidence of seedling diseases of sunflower and the major causal organisms associated with these diseases, as well as the efficacy of the standard seed treatment to control the most important pathogens. The first phase of the project involved surveys and sampling of diseased sunflower seedlings and morphological and preliminary molecular characterization of fungi associated with diseased tissues. The second phase included the final molecular characterization of the potential pathogens and the evaluation of their pathogenicity and virulence and the effect of the standard seed treatment on survival, growth, root, hypocotyl and cotyledon rot severity under glasshouse conditions. Since it was found that the standard seed treatment is not effective against many of the virulent pathogens identified in this study, the third phase of the project evaluated other seed treatments against these pathogens. Species or anastomosis groups of Alternaria, Bipolaris, Curvularia, Epicoccum/Phoma, Diaporthe, Fusarium, Macrophomina, Nothophoma, Pythium, Rhizoctonia and Setosphaeria were included in the seed treatment trials. Four chemical products and three biological products were included in the study. This study showed that the chemical products were the most effective and that there are chemical products that performed as well and in certain instances better than the standard seed treatment (ST5). Also important is that these compounds were not phytotoxic to the seedlings. Since it is known that soilborne pathgens are often part of a complex that cause disease, the fourth phase of the research evaluated the effect of the chemical seed treatments against different complexes of the most virulent soilborne pathogens identified in this study viz. Fusarium solani species complex, P. irregulare, P. ultimum and the anastomosis groups (AGs) AG 2-2LP, AG 4HGI, AG 4HGIII and SB3 within Rhizoctonia solani. The effect of the chemical seed treatments against different combinations of these pathogens were tested. Seven mixes of the different pathogens were included as follows: Control (no pathogen), mix 1 [Fusarium solani species complex (FSSC)], mix 2 (both Pythium spp.), mix 3 (all four R. solani AGs), Mix 4 (FSSC and both Pythium spp.), mix 5 (FSSC and all four R. solani AGs), mix 6 (both Pythium spp. and all four R. solani AGs) and mix 7 (FSSC, both Pythium spp. and all four R. solani AGs). The total inoculum concentration for each mix was 0.5% mass inoculum/mass planting medium. Four chemical products [ST2 = Experimental Code BYF14182 from Bayer Crop Science with a.i. not disclosed + Cruiser® 600 FS from Syngenta with a.i thiamethoxam (insecticide); ST3 = Experimental Code BYF14182 from Bayer Crop Science with a.i. not disclosed + Cruiser® 600 FS from Syngenta with a.i thiamethoxam (higher dosage than ST2); ST4 = Cruiser® 600 FS from Syngenta with a.i thiamethoxam (insecticide); ST5 = Celest® XLfrom Syngenta with a.i. fludioxonil and mefenoxam + Cruiser® 600 FS from Syngenta with a.i thiamethoxam (insecticide) (standard registered seed treatment for sunflower); ST6 = Maxim Quattro® from Syngenta with a.i. thiabendazole, azoxystrobin, fludioxonil and mefenoxam + Cruiser® 600 FS from Syngenta with a.i thiamethoxam (insecticide)] were tested for their effect on survival, growth and root and hypocotyl rot on sunflower seedlings under glasshouse conditions. Seed treatment ST1 was untreated seed. Results showed that survival of seedlings in soil inoculated with pathogen mixes 3, 4, 5, 6 and 7 were significantly reduced when planted to untreated seed (ST1). In soil inoculated with these mixes, seed treatment ST6 significantly improved survival and the highest survival rates were recorded in these soils for seed treatment ST6. Other seed treatments that also significantly improved survival in soil inoculated with these pathogen mixes were ST2, ST3 and ST5 with ST2 and ST3 performing better that ST5 in soil inoculated with pathogen mixes 3, 5, 6 and 7 and performing the same as ST5 in soil inoculated with pathogen mix 4. All the pathogen mixes except mix 6 significantly reduced the growth of seedlings with the greatest reductions caused by mixes 1, 4, 5 and 7. None of the seed treatments significantly improved growth in soil inoculated with mixes 1 and 7, and all seed treatments improved growth in soil inoculated with mix 3. Only seed treatment ST6 significantly improved growth in soil inoculated with mixes 2, 4 and 5. All the pathogen mixes caused significant root rot, with the highest being reported for pathogen mixes 1, 4, 5 and 7. Seed treatment ST6 was the most effective treatment to reduce root rot caused by mixes 1, 4 and 7 while treatments ST3, ST4, ST5 and ST6 significantly reduced root rot of seedlings in soil with mix 5. Seed treatment ST2, ST3, ST4, ST5 and ST6 significantly reduced root rot severity caused by mix 6. There were no difference in root rot severity of seedlings from seed treated with any of the seed treatments and planted in soil with mixtures 2 and 3. The highest hypocotyl rot severities were recorded for seedlings planted in soil inoculated with mixes 1, 4, 5, 6 and 7. None of the seed treatments caused any reduction in hypocotyl rot severity of seedlings in soil inoculated with mix 1, but all the seed treatments significantly reduced hypocotyl rot severity caused by mixes 4 and 6 and seed treatments ST3 and ST6 significantly reduced hypocotyl rot caused by mix 5. Seed treatment ST6 significantly reduced hypocotyl rot caused by mix 7. Considering that one of the most important functions of an effective seed treatment is to protect seedlings against damping-off it is clear that there are treatments such as ST6 and also ST2 and ST3 that performed better than the standard seed treatment ST5 when challenged with different combinations of the most virulent soilborne pathogens of sunflower seedlings. Since many of the soilborne pathogens affecting sunflower seedlings have a broad host range and crop rotation is widely practiced as part of conservation agriculture, effective seed treatment can play a significant role to ensure proper establishment of seedlings and should be included in an integrated management strategy against soilborne diseases of sunflower. The current study demonstrated the ability of seed treatments which included combinations of active ingredients to effectively target a complex of pathogens associated with sunflower seedlings to significantly improve survival, growth and reduce root and hypocotyl rot severity. The results obtained under glasshouse conditions showed that it would be worthwhile to evaluate these treatments under field conditions in different production areas with different disease complexes and climatic conditions in order to confirm the positive results obtained in the glasshouse study, and to motivate for registration of products that effectively controlled the most virulent pathogens of sunflower seedlings.
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National soybean cultivar trials
A total of 28 commercially certified cultivars were evaluated for the cool, moderate and warm areas, for the 2019/20 season in 21 field trials. Only GMO cultivars were included in the trials and Roundup applications were used during the execution of the trials. A randomised latinised row/colum design with three replicates was used for all field trials. Date of flowering (50% flowering), date of harvest maturity, length of growing season, plant height, pod height, green stem, lodging, shattering, 100 seeds mass, undesirable seed and the yield probability of cultivars calculated. Yield probabilities served as guideline for cultivar selection.
The mean number of days from planting to 50% flowering of cultivars for the cool, moderate and warm areas were 71, 58 and 50 days respectively. The overall mean yield was 3 429kg ha-1 for the cooler areas, 3 137kg ha-1 for the moderate and 2 818kg ha-1 for the warm areas. Cultivars with a high yield probability are important in the selection of cultivars by producers due to the reliability of the expected future yield. DM 5351 RSF and PAN1521 R for the cooler areas; NA5509 R, LS6860 R, DM6.8i RR for the moderate and P61T38 R for the warmer areas can be regarded as all-rounders' with a yield probability >50% for all the yield potentials.
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Sclerotinia sclerotiorum disease potential and management responses in soybean and sunflower
Title Change
Title changed from: "Identifying pathogen x environment stimuli driving Sclerotinia sclerotiorum epidemic responses in sunflower and soybean genotypes and their application in risk management" to "Sclerotinia sclerotiorum disease potential and management responses in soybean and sunflower."
Introduction
The fungal pathogen Sclerotinia sclerotiorum has an intriguing epidemiology as it has the potential to cause plant diseases in more than 500 host species (Bolton, Thomma & Nelson, 2006). In South Africa, primary risk crops are soybean and sunflower, with an increasing risk to canola (Ramusi & Flett, 2015). The economic importance of many of the crops affected by Sclerotinia spp. emphasises the need for effective disease management strategies. Management of these diseases is limited by the extensive host range and duration of survival of sclerotia in soil, as well as the lack of registered active ingredients for chemical control, or available material for conventional resistance breeding. Cultivar selection is the preferred method of Sclerotinia disease management in South Africa, as it is economically viable. The development of cultivars resistant to Sclerotinia diseases would be ideal as it would provide producers with a longer-term solution to reduce disease risk. Timely fungicide applications, at critical host growth stages, can provide an effective management strategy for Sclerotinia diseases. Currently, there are a limited number of registered preventative active ingredients in South Africa for fungicide use. These are limited to only pea and sunflower and include benomyl and procymidone (CropLife, 2015). Models used to forecast diseases caused by Sclerotinia spp. vary in complexity from relatively low input point system models to more complex, multivariate systems. The importance and potential value of crop disease prediction models in the optimisation of timing of intervention practices for disease management was demonstrated by Prandini et al. (2009). An important consideration is the number of variables included in the models and the need for a balance between what is practical in the field versus disease risk prediction accuracy. The sporadic nature and complexity of diseases caused by Sclerotinia spp. complicates the identification of tolerant genotype sources and the validation of forecasting models (Saharan & Mehta, 2008). To understand the host response, it is important to determine the infection pathway of S. sclerotiorum under controlled and field conditions and identify critical growth stages and tissues, as well as quantify the patho-system interactions and management implications.
Aim
The project is aimed at identifying driving variables associated with Sclerotinia epidemic development in soybeans and sunflowers, from a multiple management strategy perspective, including pathogen (infection pathway), host (cultivar evaluations), environment (validating the weather variables interaction with host x pathogen) and intervention (chemical control strategies).
A Note on Research Dynamics
As we conduct this research and interact with producers, as well as industry members, we are seeing the need for practical short-term answers and solutions. I would like all involved to be cognisant of the dynamics associated with research projects and the need to at times, adjust the course of the research to better approach the questions asked. This may require a change in methodologies or addressing secondary questions that arise.
Objectives
There are two tiers to this project, i.e. development of a risk model and investigation of the pathogen x host responses with the respective driving variables:
- Validation of critical host growth stages and weather variables associated with epidemic initiation and development is one of the primary steps towards a risk model.
- Pathogen X Host Responses:
- Infection pathway
Identifying the tissue which is most susceptible to infection and the respective critical growth stages could assist in increased inoculation efficiency for cultivar evaluations, indicate tissues of interest when identifying tolerance/resistance mechanisms and provide specific cultivar inoculum x tissue interactions.
- Cultivar evaluations
Commercially available cultivars (local and international (Argentina) – study of this material has already been initiated) will be targeted.
- Fungicide evaluations
Identifying the most efficient chemical and management strategy to control an epidemic and the host response that would contribute towards the risk model. These evaluations will most likely be restricted to soybean production initially, as no products are registered for soybean production.
- Infection pathway
First quarter progress report (January-March)
- Validation of relationship between weather x host x pathogen
Survey data are being collected to add to a validation data set and field trials are being conducted and monitored in Delmas, as well as Clocolan. The mathematics and statistics of this section is underway as part of Mrs Lisa Rothmann's PhD to be completed in 2019. She is currently in Brazil to further the understanding of a risk model development under the guidance of Professor del Ponte, Federal University of Viçosa, MG, Brazil. Funding was granted by the NRF KIC Grant.
- Infection pathway
This section of the study has not been started and will only start in 2019/2020 season, as Ms Marlese Bester will only receive her M.Sc qualification (marked, evaluated and completed) in April, at which point the study can be officially started as part of her PhD. We have ordered two sets of primers to test the ability and specificity of the primers so that when trials are conducted the molecular aspects are ready for evaluation. The inoculation techniques were optimised and Ms Besters M.Sc study methodology will be applied here.
- Cultivar evaluations
Field trials are currently underway and 18 soybean and 21 sunflower cultivars are being evaluated in Delmas across four planting dates. The technique described by McLaren (1992, 2000, 2002) for sorghum ergot, Stenocarpella cob rot of maize (Flett & McLaren 2004) and McLaren and Craven (2008) will be applied to this season's cultivars for further validation of the technique. We met with the germplasm owners at a Farmers Day (SantaRosa, Argentina) and explained our research to their breeders, agronomists and stakeholders. The trials are looking promising and a high incidence of sclerotinia is being observed in the field. We have taken ratings for the first two plantings. The last two plantings will be evaluated across the next month to month and a half. We are also working in collaboration with a producer in Clocolan, Mr. Koos Strydom, where we planted two plantings of 21 sunflower cultivars to increase the diversity of disease potentials under which evaluations are conducted. Unfortunately, due to the extreme weather only one planting had sufficiently good germination to continue with the evaluations.
- Fungicide evaluations
In the above trials, we have incorporated 4 fungicides and all the cultivars to determine fungicide x genotype interaction on efficacy. Fungicides which were included are Pyridine - carboxamide (252g/kg); Benzimidazole (500g/kg), Procymidone (dicarboximide; 250g/l) and Pyrimethanil (aniline derivative; 400g/l). We have inoculated and uninoculated (natural inoculum trials) controls included in both this trial and the cultivar evaluations, allowing for different degrees of severity to be recorded. The inoculation techniques were optimised and Ms Besters M.Sc study methodology was applied here and above in the cultivar evaluations. At a first glance, we are able to detect visual difference between fungicide treatments, cultivars as well as interactions between cultivars x fungicide and final evaluations will be forthcoming.
Second quarter progress report (April-June)
- Validation of relationship between weather x host x pathogen
Survey data were collected to add to a validation data set from field trials conducted and monitored in Delmas (Soybean and Sunflower), as well as Clocolan (Sunflower).
Ms. Rothmann has also arranged for an MoU between the Federal University of Viçosa and UFS to be signed by both rectors. This trip is fully financially supported by the NRF KIC Grant, which she and Professor McLaren applied for last year. She will be visiting from the 15th of June until the 3rd of August 2019.
- Infection pathway → Initial point of infection
During our formal project proposals (10 June 2019) with academic staff of the Plant Sciences Department it was suggested and accepted that this chapter of the study should be removed from the PhD project as there are too many unknowns regarding the pathogen x host x environment responses. Furthermore, the feasibility of this study in the glasshouse was questioned, due to the physiological response of the host in the glasshouse compared to the field. The suggestion was also to only look into this once a better understanding of the fungicides available were clarified, as this could give rise to two separate chapters associated with the application of fungicides to ensure maximum efficacy upon application. This will not change the budget of the proposal, as we have included a new chapter, which has two research components which would allow for us to test the survival and viability of sclerotia under fire and in the digestive tracts of cattle, sheep or both. Please see below for more detail.
- Cultivar evaluations
Field trials have been completed where 18 soybean and 21 sunflower cultivars were evaluated in Delmas across four planting dates in collaboration with Dr. Derick van Staden. These data are being compiled and the data workflow is being organised.
We are also working in collaboration with a producer in Clocolan, Mr. Koos Strydom. Two plantings of 21 sunflower cultivars were anticipated, however due to the extreme weather, only one planting had sufficient germination to continue with the evaluations. We have manged to salvage some of the second planting and are to complete the trials there by the end of May 2019. These data will be added to the above data workflow file.
We have planned to work with Ms Annelie de Beer for the 2019/2020 season, this will require more driving for our study to the National Cultivar Trials which have sclerotinia reports which Ms de Beer will inform us of in the new season.
- Fungicide evaluations
We have completed the fungicide evaluation trials and are entering into discussions between UFS and Dr. Derick van Staden on how to further develop these trials to benefit our producers. These data are being compiled and organised into a data workflow file as well.
We will have to enter into a nondisclosure agreement (NDA) with Dr. van Staden in order to proceed with this portion of the study, as instructed by the Directorate of Research and Development at the UFS. This will not affect the MoU as signed by the UFS and Grain SA.
- Inclusion of alternative management strategies
The effect of fire and bovine rumen on sclerotia survival and viability are proposed as additional research topics as these questions are continuousky raised by producers.
The samples will be collected during the winter period as the fields are used for grazing. If this is not possible in 2019, we will collect samples in 2020. We already have a producer who we are working in close relationship with in Clocolan, Mr. Koos Strydom, who will also be able to point us towards other producers in the area who are willing for us to sample with him.
The effect of fire will be tested under simulation scenarios at the laboratory. This will include the evaluation of sclerotial germination under a range of high oven temperatures and duration periods.
We will also make use of the surveys, which will make use of the Sclerotinia.co.za website for empirical data to highlight the importance of on farm practices in relation to Sclerotinia incidences. These would serve to justify future research topics, beyond the scope of this PhD study, for the best management of Sclerotinia epidemics.
Therefore, the revised aim
The project is aimed at identifying driving variables associated with Sclerotinia epidemic development in soybeans and sunflowers, from a multiple management strategy perspective, including the pathogen (survival and viability), host (cultivar evaluations) and environment (validating the weather variables interaction with host x pathogen).
Conclusion
We are pleased with the progress and timeline of the research components covered over the second quarter, and will be pleased to visualise and report on this data within the next two quarters. We are also please to know that Mr. Koos Strydom has agreed for us to continue working on his farm with him towards completing our research goals.
Third quarter brief plans (July-September)
- Data analysis of 2018/2019 data collected for the cultivar evaluations.
- Regional risk model development in Brazil.
- Collection of dung samples at multiple locations, the removal of sclerotia from dung and the evaluation of viability of these.
- Collection of fresh sclerotia for the fire trials, from infected soybean and sunflowers.
- Testing artificial semi-selective media for Sclerotinia sclerotiorum ascospores using ascospores collected over the season to test the media's effectiveness.
- Start planning for the 2019/2020 season.
- Start collecting survey responses from the Sclerotinia.co.za website.
- Prepare Marlese Bester's M.Sc cultivar evaluation chapters for publication.
Long term goal
Launch a functional regional risk model through the website, which may take 3 to 5 years depending on the data available for the predictions and the collaboration of producers in the future surveys and field trials – this will be applicable to Soybean and sunflower and, permitting Canola through the collaboration with Prof McLaren and the Western Cape Department of Agriculture.
Standardized cultivar evaluation protocol for sclerotinia in soybean and sunflower.
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Website
After successfully presenting a demo of OPDT/OAC's new website in November 2018 work commenced to update all existing content. This included code validation in preparation for the major PHP 7.2 ** upgrade scheduled for September 2019 on the hosting server. The new website was officially launched in August 2019 and on 29 February 2020 the OPDT/OAC's website hosted a total of 375 HTML pages (excluding dynamically created pages).
** PHP is the base programming language that is used to output website content to the browser.
During November 2020 the OPDT/OAC took over ownership of the following domains:
- ssa.org.za
- soyfood.co.za
A new section for "Soyfood" was created on the website and the content previously hosted on ssa.org.za has been incorporated into this section.
Reporting Year Unique Visitors (Raw values *) Unique Visitors (Google values) * Visitors Pages Pages per visit 2007 11 – – – 2008 74 – – – 2009 752 – – – 2010 2 964 – – – 2011 4 037 788 3 284 3.21 2012 4 052 720 3 775 4.25 2013 4 342 674 3 296 3.94 2014 4 503 1 086 4 600 3.62 2015 4 800 1 340 6 993 4.14 2016 4 329 927 5 042 3.83 2017 6 384 909 5 406 4.39 2018 5 428 1 841 8 885 3.59 2019 8 307 1 661 8 340 3.43 Google values show an increase in page views and a significant increase in unique visitors. Pages per visit decreased moderately. The most page views came from the following pages in order of percentage share:
- Home page, 15.63%
- Oilseeds Focus Magazine, 3.07%
- Contact Us, 2,98%
- Bursary Application, 2.77%
- Crops, 2.27%
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Oilseeds information
During the 2019/20 financial year the Oilseed Industry held six forum meetings. The General Manager, Mr Nico Hawkins, attended four forum meetings where the information of SAGIS was presented and distributed to all role players. At the other two meetings the information of SAGIS was also distributed to all attendees and were also made available on the website of SAGIS.
SAGIS' Board of Directors during the 2019/20 financial year
Dr Erhard Briedenhann and Mr De Wet Boshoff with Ms Marie van der Merwe as their alternate represented the Oil and Protein Seeds Development Trust and oilseeds industry on SAGIS' Board of Directors.
Dr John Purchase and Ms Mariana Purnell were the Chairperson and Vice Chairperson of SAGIS' Board.
Financial year 2019/20
Subscription: Main Function (VAT excluded)
A net amount of R14 615 769 was approved by the Members for utilisation during the 2019/20 financial year and the final expenditure amounts to R14 615 769. This included an amount of R846 360 that was foreseen to adjust the current computer system to be compatible with new technology.
The portion of the Oil and Protein Seeds Development Trust was R2 309 291.50 (VAT excluded).
Audit
The audit of the 2019/20 financial statements was conducted by "The Ashton CA (SA) Group Inc." and an unqualified audit report was issued.
General Information
Co-workers in the Oilseeds Industry
The number of returns per commodity in the oilseeds industry, at 29 February 2020, was as follows:
Commodity 28 February 2018 28 February 2019 29 February 2020 Canola 28 26 21 Groundnuts 81 80 75 Soybeans 108 110 108 Sunflower 113 115 107 Total 330 331 311 Product Information
An amount of R81 625 (VAT excl.) was approved by the Trust for the Product Information. This was sufficient to cover all expenses for the 2019/20 financial year.
The publication dates are available on SAGIS' website. On 29 February 2020 the actual number of returns from registered co-workers was 81 returns for the oilseed industry.
Weekly information
An amount of R86 150 (VAT excl.) was approved by the Trust for the Weekly Information. This was sufficient to cover all expenses for the 2019/20 financial year.
The publication dates are available on SAGIS' website. On 29 February 2020 the actual number of returns from registered co-workers was 40 returns for the oilseed industry.
Inspections for oilseeds
Visits at co-workers
The following visits were made at co-workers of oilseeds per commodity:
Commodity Commodity Audited Oilseeds: – Canola 16 – Groundnuts 56 – Soybeans 84 – Sunflower 89 Products: – Oilseeds Milling Industry 55 – Oilseeds Products: Imports/Exports 19 Total 319 Stocktaking
The following physical stocktaking of oilseeds was done from 1 March 2019 until 29 February 2020:
Canola Groundnuts Soybeans Sunflower 29 512 8 373 543 096 71 664 Conclusion
SAGIS appreciates the support and co-operation of all the role-players.
We wish to express our gratitude especially towards the Members of the Oil and Protein Seeds Development Trust for their continued support, financially and otherwise.
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Cultivar evaluation of oil and protein seeds in the winter rainfall area: Western and Southern Cape (canola)
Introduction
In the 2019 season, a total of 17 cultivars were tested in the cultivar evaluation program. Six conventional, four CL (Clearfield, Imazamox tolerant) and six from the TT (Triazine tolerant) group were included in the program. One new CL cultivar 45Y93 and a new combination type cultivar, namely Imazamox and Triazine tolerant cultivar, (Hyola 580CT) were tested. All 17 cultivars are hybrid cultivars, as in the past few seasons.
Climate
This past season in the Swartland was characterized by below average rainfall, although the rainfall was close to normal during July. This rainfall in 2019, expressed as a percentage (%) of the long term, ranged between 53% and 86%. Langgewens received 199mm in 2019 compared to a 12 year average of 306mm for the period 1 May to the end of October. Throughout the region, there was very low monthly rainfall in August and September with very hot temperatures during September were extremely negative for yield in 2019.
In the Southern Cape, sufficient rainfall occurred during March, with weather stations measuring from 52mm to 107mm. However, Tygerhoek measured as much as 299mm of rain during March. Plantings were done early in the eastern and central parts of the Southern Cape. The western areas start planting in early May. The soil moisture was good initially, but due to the occurrence of too little rain during the growing season, some plantings failed. The rainfall in 2019 expressed as a percentage (%) of the long term ranged from 41.1% to 80.5% (May to October). The average maximum temperature at Tygerhoek was above average throughout the growing season with the exception of September which was 5ºC higher than average.
Results
During the past season, the Swartland trials were exposed to very dry conditions with very high temperatures during flowering and seed-filling periods. Very few Sclerotinia occurred in 2019. White-leaf spot, like the past few seasons, occurred at Grasrug. The incidence was high and the trial also sustained hail damage during the rosette stage. In the Swartland, the average yields were 1 362kg ha-1 versus 2 113kg ha-1, 1 777kg ha-1 and 2 746kg ha-1 in 2018, 2017 and 2016 respectively.
All trials, with the exception of the second planting date at Langgewens (May 27), were planted between May 10 and May 16. The trial averages for the Swartland ranged between 629kg ha-1 for Eendekuil and 2 543kg ha-1 for Philadelphia.
The conventional cultivar Diamond (1 775kg ha-1) was the highest yielding cultivar in the Swartland. However, Diamond's yield was not significantly higher than Quartz (1 765kg ha-1) in 2nd place. The yields of CB Tango, Hyola 50, Belinda and Agamax were significantly lower than those of Diamond and Quartz.
The CL cultivar with the highest yield in its group was 43Y92 (1 586kg ha-1) followed by 44Y90 (1 345kg ha-1). The yield of 43Y92 was significantly higher than 44Y90, 45Y93 (new CLl) and 45Y91.
Alpha TT was also the TT cultivar with the highest average yield in the Swartland (1 449kg ha-1). The yield was not significantly better than Hyola 350TT (1 395kg ha-1) in second place. The new combination type cultivar namely Imazamoks and Triazine tolerant cultivar (Hyola 580CT) had an average yield of 1 084kg ha-1. Hyola 350TT yield was significantly higher than Hyola 559TT, Hyola 650 TT, Hyola 555TT, Hyola 580CT and Atomic. The average yield of the TT cultivars in 2019 was 20% lower than the conventional cultivars. In the 2018 and 2017 seasons, yields were down 12.7% and 9.8%, respectively. The yield of the CL cultivars was on average 4% lower than the yield of the conventional group of cultivars.
In the Rûens, the trial averages varied between 1 981kg ha-1 at Napier and 1 193kg ha-1 at Tygerhoek. The average yield was 1 732kg ha-1 compared to 2 270kg ha-1 in 2017 and 2 240kg ha-1 in 2016.
The conventional cultivar Quartz (2 231kg ha-1) has the highest yielding cultivar in the conventional group as in 2018. This was followed by Diamond (1 979kg ha-1). The highest yielding CL cultivar in the Southern Cape was 43Y92 (2 069kg ha-1). The 44Y90 cultivar (1 972kg ha-1) was 2nd in the CL group. In 3rd place was 45Y91 followed by 45Y93. In the TT group, Alpha TT (1 829kg ha-1) delivered the highest yield, followed by Hyola 350TT (1 665kg ha-1) and Hyola 650 TT (1 610kg ha-1) in third place. The average yield of TT cultivars was 17% lower than conventional and CL cultivars. In 2018, the difference was 9.3% versus 9% in 2017. On average, the CL and conventional cultivars differed by only 3kg ha-1 in yield.