PhD Scholarship in Arable Crop Production
Effects of organic and conventional rotation design, crop protection and fertilisation regimes and variety choice on wheat and soya crop health, yield and nutritional quality
Organic crop production standards prohibit the use of synthetic chemical pesticides and mineral N, P and KCl fertilisers that are commonly used in conventional arable crop production. Organic producers often grow older varieties (varieties introduced pre 1980s with longer straw) and more recently have started to use varieties specifically bred/selected for organic farming systems.
Recent systematic literature reviews and factorial field experiments in the UK reported that organic cereal production protocols result in a significant reduction in crop yields, foliar disease severity and lodging, pesticide residues and cadmium levels, but higher antioxidant, nitrate/nitrite and zinc concentrations in cereal crops (Cooper et al. 2013; Baranski et al. 2014, Rempelos et al. 2018). However, most comparisons included in meta-analyses were from temperate climatic zones with relatively high rainfall, while there is limited data from arable production (both irrigated and non-irrigated) systems in semi-arid regions such as Australia. Also, there is virtually no information on the effect of organic production protocols on the crop health, yield and nutritional quality parameters in soya and there is no information from semi-arid arable production environments on the relative contribution of contrasting agronomic factors (e.g. rotation design, crop protection, fertilisation, variety choice) on the differences in crop health, yield and nutritional quality parameters between organic and conventional cereal and grain legume crops field vegetable production systems. However, studies in UK demonstrated that the relative effect of (and interactions between) specific agronomic factors (pre-crop, crop protection and fertilisation) on health, yield and nutritional quality parameters in wheat crops can be identified and quantified in long-term, factorial field trials (Cooper et al. 2013; Rempelos et al. 2018).
The SCU/NSW-DPI Centre for Organics Research (COR) and Southern Cross Crop Science have established a unique factorial field experiment in collaboration with SOFT Agriculture at Mallanganee, NSW. Experiments are designed to identify/quantify effects of (and interactions between):
- crop protection (with and without the use of pesticides),
- fertiliser type (mineral NPK vs composted cattle manure),
- variety/hybrid choice and
- rotation design on crop health, yield, nutritional and sensory quality parameters in wheat and soya. Soil chemical, physical and biological, environmental impact and production cost parameters will also be recorded in these experiments to allow both financial and environmental cost/benefit analyses.
- Barański, M., Średnicka-Tober, D., Volakakis, N., Seal, C., Sanderson, R., Stewart, G.B., Benbrook, C., Biavati, B., Markellou, E., Giotis, H., Gromadzka-Ostrowska, J., Rembiałkowska, E., Skwarło-Sonta, K., Tahvonen, R., Janovská, D., Niggli, U., Nicot,P. and Leifert, C. (2014) Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analysis. British Journal of Nutrition 112, 794–811.
- Cooper, J., Sanderson, R., Cakmak, I., Ozturk, L., Shotton, P., Carmichael, A., Sadrabadi Haghighi, R., Tetard-Jones, C., Volakakis, N., Eyre, M., and Leifert, C. (2011) Effect of organic and conventional crop rotation, fertilization and crop protection practices on metal contents in wheat (Triticum aestivum). Journal of Agricultural and Food Chemistry 59, 4715–4724.
- Rempelos, L., Almuayrifi, A.M., Baranski, M., Tetard-Jones, C., Eyre, M., Shotton, P., Cakmak, I., Ozturk, L., Cooper, J., Volakakis, N., Schmidt, C., Sufar, E., Wang, J. Wilkinson, A., Rosa, B.A.S., Zhao, B. Rose, T.J., Leifert, C. and Bilsborrow, P. (2018) Effects of agronomic management and climate on leaf phenolic profiles, disease severity and grain yield in organic and conventional wheat production systems Journal of Agricultural and Food Chemistry DOI: 10.1021/acs.jafc.8b02626
The project will focus on quantifying the effects of (and interactions between) contrasting:
- rotation designs,
- crop protection protocols (with and without applications of synthetic chemical pesticides),
- fertiliser types (mineral NPK, vs composted cattle manure) and
- variety choice on crop health, yield, nutritional and processing quality parameters in wheat and soya.
The work will include:
- Targeted critical review of existing relevant peer-reviewed scientific literature
- Systematic literature review and meta-analyses of studies reporting comparative data on antioxidant/phytochemical and mineral concentrations in organic and conventional wheat and soya crops
- Assess weed density, disease and pest severity and crop yield and visual quality parameters in wheat and soya crops
- Design and setting-up of farmer-participatory field trials
- Collect soil, leaf and grain samples in field trials for laboratory analyses
Carry out relevant phytochemical analyses including calorimetric assays for antioxidant activity and HPLC based analyses of nutritionally relevant antioxidants and phytochemicals at the SCU plant science labs in Lismore
This studentship would be suitable for a graduate in agricultural, biological, environmental or related sciences. The student will receive training in:
- Soil and crop management in organic and conventional arable crop production systems
- Critical and systematic review of scientific literature and meta-analysis methodologies
- Experimental design, data management and statistical analyses using R
- Establishment, management and assessment of crops of field experiments
- Extraction and analytical protocols of plant phytochemicals
- Writing research papers for peer-reviewed scientific journals
- Preparing reports and preparing presentations for scientific audiences, farmers/growers and consumers
In addition, this studentship will be managed within the postgraduate training programme in Plant Science Innovation, which provides opportunities to benefit from a broader range of professional training alongside the focused research project.
Links to ongoing work and potential collaboration
The Centre for Organics Research (COR) is a joint research centre between Southern Cross University and NSW Department of Primary Industries which conducts research in partnership with community and industry stakeholders. The Centre for Organics Research provides strong evidence-based scientific and multidisciplinary research focused on clarifying some of the complex issues surrounding organics production and supply chains. This includes research into the comprehensive reach of organic production covering such broad themes as integrated production systems, sustainable resource management, economics and markets, and education and health.
Southern Cross Plant Science is a Research Centre within Southern Cross University, and carries out research underpinning the selection, cultivation and utilization of plants. SCPS infrastructure includes facilities for plant growth, analytical chemistry, high-throughput DNA sequencing, genotyping, proteomics and bioinformatics. The candidate will also benefit from expertise and experimental resources available within the wider Southern Cross University research environment. Southern Cross University has achieved the highest rating of exceptional performance, well above world standard in the past two national assessments of research excellence (2012 and 2015) for crop and pasture production and agricultural science.
COR has developed a close working collaboration with SOFT Agriculture, who support the management of the two factorial field trials used in the PhD research project.
Value of scholarship
Three years at $30,000 per annum.
This project will be based at SCU’s campus in Lismore, NSW, Australia, and will involve the student in working in the context of an industry-sponsored collaboration.
Deadline for applications
Friday 29 March 2019.