Key Points
Cultivars Muscat and County (May sown) and Optic and County (September sown) were established in both dryland & irrigated areas at the FAR Arable Site with 3 sowing rates and 2 nitrogen timings, repeating a similar trial the previous season. For the second year in succession Muscat suffered from severe neck break.
- For May sowings:
- There was no yield benefit from increasing populations above 100-150 plants/m2.
- With 108kg N/ha residual N, nitrogen timings at GS30 or GS32 made little difference at 100 plants/m2, although with higher populations yields were reduced if N was delayed until GS32, especially on dryland.
- TGW & screenings tended to decrease with higher populations, and scald was observed to increase.
- For September sowings:
- The highest yields occurred at 200-300 plants/m2.
- Dryland County preferred N later at GS30. Dryland Optic tended to prefer N earlier at GS11. If irrigated, both cultivars tended to prefer N early at GS11 – screenings increased for Optic if N was delayed.
- Screenings tended to be least at 200-300 plants/m2 on the dryland (unlike the previous season) but population effect was negligible if irrigated.
- The September sown dryland plots retained approximately 2 to 3 times more ears/m2 (at harvest) than if May sown or irrigated.
- In 2003/04 after applied nitrogen (GS32) being slightly advantageous on May sowings but detrimental with September sown crops (FAR Arable Update Cereals No.144).