Take home messages

• Be clear on why you want to grow faba beans, assessing the potential benefits and risks.
• Choose a variety that best suits your farming system and combines the traits that manage your key risks. PBA Amberley is the faba bean variety that is likely best suited to the HRZ of Tasmania due to its potential yield and disease resistance.
• Prepare your soil – minimise key constraints like low pH and compaction.
• Plan your management – given the high rainfall, disease management will be crucial using a strategic integrated approach including SDHI fungicides at critical phases (pre-flowering). Minimise your weed competition by considering newer product options and ensuring good control throughout other phases of the farming system.

Introduction

Faba beans have continued to grow as a key rotational crop in Australia with approximately 650,000t produced off 300,000ha in each of the last three cropping seasons. Generally, 80% of the crop is grown in South Australia and Victoria, with 15% in New South Wales and the rest distributed across Western Australia, Queensland and Tasmania.

The primary areas of production are in medium and high rainfall zones. While the ideal soil for faba beans is a deep, well structured, alkaline loam to clay loam, they will tolerate a broader range of soil textures and pH than other pulse crops. In addition, they are the best pulse option for soils prone to waterlogging. These factors combined indicate potential in Tasmania, but how can we achieve long term profit stability that is competitive with alternative crops and farming systems?

Here, we explore opportunities too make faba beans a ‘gem’ of a crop in Tasmania by using the Genotype (G) x Environment (E) x Management (M), principles. A gem can be precious or semi-precious stone of high value, especially when cut and polished or engraved. Currently beans in Tasmania are like the newly discovered stone, a bit rough and dirty, but ready to be polished into something valuable. GxExM is an acronym that provides a framework to help achieve optimum profitability for the crop in your farming system.

Genotype (G)

Genotype is another word for variety and allows us to think about what genes/traits we need to grow a high yielding, high quality profitable crop. Breeders can develop varieties with new traits, such as disease resistance, herbicide tolerance, flowering time, maturity, growth habit, and soil type tolerance. It’s the combination of these traits that defines the ultimate yield potential. What is the best genotype (variety) you can choose for your environment and management system?

Environment (E)

Environment refers to where you intend to grow the crop, and primarily relates to factors outside of your specific control. This includes rainfall, temperature and soil type. We can partly influence, through management and genotype (variety), the way rainfall is captured, how the crop experiences temperature and some of the chemical and structural components of soil. How will the environment influence the genotype (variety) you need to choose and what management will you need to put in place to overcome or minimise limitations of your environment?

Management (M)

Management refers to the various factors we can control in growing the crop and the farming system, for example, sowing time, plant density, stubble management, soil amendments, nutrition, fungicide and herbicide application, rotation with other crops, and use of livestock. What are the best management choices you can make given the genotype (variety) you are growing on your farm (the environment)?

If you choose the best variety (G) and optimise the management (M) for each environment (E), you can maximise profitability. Will that ensure faba beans are a ‘gem’ of a crop for your farm business and cropping system? Ultimately, only you can decide once you understand the potential profit from grain and economic benefits to your farming system.

Detailed information on how to grow a faba bean crop can be found in GRDC GrowNotes – Faba Bean Southern Region and the additional resources listed below. In addition, speaking with an experienced advisor and educating yourself of the risks and rewards is important to ensuring long term success.

Some key points to consider on why? and how? to grow faba beans are highlighted below.

It is essential before growing any crop to be clear on the ‘why’ of growing the crop. Ultimately, it is about improving profitability and economic viability (sustainability) of your farming system over the long term. There are two key things to consider before growing faba beans.

• Price and yield can be volatile, and marketing has unique challenges. In the last 10 years, the price of faba beans in Victoria has ranged from about $250/t to more than $900/t, with the average approximately $450/t. Grain yields have ranged from 0 to 6t/ha with field trials indicating that greater than 10t/ha is achievable in optimum conditions.
• Farming system benefits can be substantial, so it’s important to ensure that value is attributed across the whole system. Faba beans can contribute up to 15–20kg/ha of nitrogen per tonne of biomass produced. In addition, they provide a disease and weed break for cereal crops and stubbles can be grazed. These factors combined could be worth more than $1000/ha in addition to the returns you can achieve from the crop.

Once the ‘why’ is determined, it is essential a clear plan, the ‘how’, is implemented. Plan and prepare for success through clearly understanding your risk profile and GxExM.

• Risk – Each person and farm business will have a different attitude to risk and ability to respond to risk. Begin by calculating potential returns and losses that could occur with faba beans, then determine the key production risks: is it disease, is it weeds, is it soil type? This understanding will help to define the key decisions you will need to make regarding variety (G) choice and management (M) strategy.
• GxExM
  • Genotype (variety) – Currently, there are three main varieties which could suit the Tasmanian production system: PBA Amberley, which is high yielding in the high rainfall zone with good disease resistance; PBA Samira, which has good yield stability across a range of soil types with moderate disease resistance; and PBA Bendoc, which has tolerance to imidazolinone ‘IMI’ herbicides, but is susceptible to disease. It is also important to be aware that the faba bean program will be releasing material that combines these traits in coming years.
  • Environment – Where possible, ensure that any key soil constraints are minimised using amelioration techniques. Soil below pH 5 will greatly reduce yield potential, as will compaction and waterlogging.
  • Management – Some of the key components to consider when growing faba beans include:
    • Sowing time – Early generally optimises yield potential. In the HRZ of Victoria, mid-late April sowing is the optimum sowing window, providing a balance between yield potential and disease pressure.
    • Plant density – 20 plants/m² is the ideal plant number for high rainfall zones, allowing for good disease management and harvestability.
    • Stubble management and row spacing – faba beans are adaptable and can be grown with or without stubble and in row spacings from 15cm to 45cm. Standing stubble and wider row spacing will help reduce disease risks.
    • Soil amendments, nutrition and inoculation – Liming the soil to above pH 5.5 will optimise nutrient availability, improve yield and increase yield stability. In low phosphorus soils, faba beans will benefit from a phosphorus-based fertiliser. Inoculation with the latest strains of peat or granular inoculants is critical to optimise nitrogen fixation and plant growth.
    • Fungicide strategies – Given the high rainfall, disease management will be crucial and involve multiple fungicide applications. Using a strategic integrated approach including SDHI fungicides at critical phases (pre-flowering) is essential to optimise yield potential. Chocolate spot is likely to be the key yield-limiting disease.
    • Herbicide application – Utilising the newer products and ensuring good control of both broadleaf and grass weeds throughout other phases of the farming system is critical. Commonly, in southern Victoria, the newer herbicides Overwatch® and Reflex® are used in combination with a range of Group 5 products to provide broad spectrum control, particularly with the non-‘IMI’ tolerant varieties. In lower disease risk areas, where PBA Bendoc can be grown, alternative strategies employing Intercept® applied in-crop are utilised.

Conclusion

There are substantial opportunities for faba beans in Tasmania, particularly as new varieties combining improvements in disease resistance, herbicide tolerance and broad soil type adaptability are released. Carefully considering your risks and employing a GxExM model of thinking can ensure profitability is optimised.

Acknowledgements

The research undertaken as part of this project is made possible by the significant contributions of growers through both trial cooperation and the support of the GRDC, the author would like to thank them for their continued support. We also thank Agriculture Victoria for ongoing support.

Useful resources

GRDC GrowNotes – faba bean southern region

NVT disease rating (faba bean, Tasmania)

Grain legume extension hub, Victoria

Faba bean agronomics for Tasmania

Contact details

Jason Brand
110 Natimuk Road, Horsham VIC 3400
0409 357 076
Jason.brand@agriculture.vic.gov.au
@jasonbrand