Effect of rate and placement of phosphorus on vetch performance

Brian Dzoma1, Nigel Wilhelm2, Peter Telfer3 and Kym Zeppel1

1SARDI Loxton Research Centre. P O Box 411, Loxton SA, 5333

2SARDI Waite Research Precinct. Building 11A Hartley Grove, Urrbrae, SA 5064

3Turretfield Research Centre. Holland Road, Rosedale, SA 5350


Phosphorus (P) is an essential nutrient which influences plant growth. Inadequate P restricts root and shoot growth and other functions that reduce N fixation by legumes. Vetch (Vicia sativa), a versatile pasture legume crop that can be used for grain, pasture, hay/silage or green manure, is being grown on naturally infertile Mallee soils which are often quite deficient in P. Consequently, it struggles to achieve optimum productivity and hence less fixed nitrogen is returned to the system. This project evaluated the impact of P on vetch productivity and nodulation and also investigated placement of P at sowing on nodulation, root and shoot dry matter (DM) production. Results showed that there are productivity gains to be realised from applying P fertilisers when sowing vetch on soils with low P reserves. Application of 32 units of P resulted in shoot DM increases of 239% and 45% at Loxton and Peebinga respectively. Results also showed that deep placement of P is beneficial to early and late DM production, but can set back nodulation as the plants need the P upfront. P applications, however, need to be matched against expected productivity gains for different soil types and rainfall regions to make sure that the fertiliser applications are economically justifiable


The Australian Society of Agronomy is the professional body for agronomists in Australia. It has approximately 500 active members drawn from government, universities, research organisations and the private sector.

Photo Credits

David Marland Photography david_marland@hotmail.com Graham Centre for Agricultural Innovation, Charles Sturt University

Conference Managers

Please contact the team at Conference Design with any questions regarding the conference.

© 2015 - 2019 Conference Design Pty Ltd