The 2023 HYC Barley PGR x Harvest Date Interaction trial looked to investigate the influence of four PGR management approaches, cultivar, harvest time and canopy management regimes on 2 barley cultivars. 

• On average, a delayed harvest led to higher head loss, a higher lodging index and lower yield
• There was a significant interaction in yield between variety and PGR management with a negative response to the addition of Ethephon in RGT Planet management, whereas treatments that were solely trinexapac ethyl (Moddus Evo) based gave no response over the untreated. In contrast, PGR management in Leabrook saw the split application of Moddus Evo yield significantly more than the other PGR treatments, however this still did not yield more than the untreated plots
• Although not translating to yield, the ‘European’ approach was the most successful at reducing lodging, with a significantly lower lodging index to the double Moddus Evo, single Moddus Evo and nil PGR treatments
• Grain quality differences were largely influenced by variety and harvest date, although on average the ‘European’ PGR approach did have a statistically negative effect on test weight and retentions

Trial design: Factorial (Var x PGR x HD)

Rotation position: 2022 Canola
Soil type: Forest gravel loam
Nitrogen 0-60cm: 83kg N/ha
Colwell P (ppm) 0-10cm: 43 mg/kg
pH (CaCl2) 0-10cm: 5.9
Organic Carbon (%) 0-10cm: 2.7 %