
Farm Table says:
This research aimed to provide answers to questions about management of N or legume residues for wheat productivity.
The trial in 2016 replicated treatments in sandy soil plots at Karoonda sands combining 3 stubble treatments from the 2015 cropping season. The results summary table is presented below.
The following key takeaways are provided:
- Without N fertiliser, wheat following lupins yielded more than double continuous wheat (1.7 vs 3.6 t/ha). A further 27 % yield increase (4.9 t/ha) was achievable when 40 kg N/ha was added to wheat following lupins.
- Increasing N fertiliser inputs on a wheat crop following legumes can improve crop performance and N uptake.
- The mineralisation potential of N in a sandy soil is improved by including lupin in the crop sequence and increased N fertiliser inputs to wheat crops.
- Net N mineralisation over the fallow following lupins can be as high as 32 kg N/ha in a Mallee sandy soil