Agriseeds Advanced Yield Trial system (AYT) ran from 2003 to 2011 and tested the widest range of ryegrass cultivars, as soon as they became available, throughout New Zealand.
The system was designed to identify and evaluate high perfomance pastures in a wide range of conditions and farm types. Trials were nationwide, in the key regions of Waikato, Taranaki, Manawatu, Hawke's Bay, Canterbury and Southland. A total of 40 trials were sown during the eight years the AYT was run.
AsureQuality visited all AYT's each year, to make sure they were designed and run to accepted industry scientific protocols. Statistical analysis of final results was also audited by AsureQuality. Trials must have passed all inspections to be included in these results.
AsureQuality independently audits all AYT's.
Independent trial operators
The trials in the AYT system were run by a range of organisations and individuals. Thanks must go to the following:
Trials at Newstead in the central Waikato under dairy cow grazing.
Trials at the Whareroa Research Farm close to Hawera under dairy cow grazing.
Trials close to its campus at Palmerston North, under dairy cow and sheep grazing.
Trials at its Poukawa Farm and in the local area of Hawke's Bay, under sheep grazing.
Trials at its campus in Canterbury, under sheep grazing.
Agriseeds also ran a number of AYT's in Waikato, Canterbury and Southland.
The AYT's were analysed using five seasons, with the traditional ‘spring’ period split into ‘early spring’ and ‘late spring’, to give more meaningful information for farm systems. Seasons are:
- Autumn: March, April and May
- Winter: June and July
- Early spring: August and September
- Late spring: October and November
- Summer: December, January and February
All cultivars in each trial were treated equally. Trials were run under moderate-high soil fertility, with the equivalent of around 100 kg N/ha/year applied, and rotationally grazed when the highest yielding entry reached about 2500-3000 kg DM/ha.
Prior to each grazing a yield cut was taken, totalling 10-13 yield cuts/year depending on weather, with DM samples analysed for every plot. Post grazing, trials were trimmed if any unevenness in grazing had occurred.