Key Points
- Moddus applied at GS32 increased the yield in all ryegrass types except for Quartet (late flowering tetraploid) in the 2001/02 season.
- There was an increase in yield as the rate of Moddus increased, up to at least 1.6l/ha. In perennial types this was a 33% increase and in Italian types a 66% increase in yield. The yield increase was similar in both 1stand 2ndyear Nui ryegrass crops.
- At low rates of Moddus, the addition of Opus in some trials gave small non significant yield increases.
- Use of Moddus did not reduce shattering but did allow later cutting times and also allowed direct heading.
- Although Moddus shortened crops and the stems were thicker and stiffer and lodging was reduced, the total dry matter production was not reduced. Generally yield increased as lodging reduced.
- The use of wild oat herbicides within two weeks of applying PGR may explain why the Quartet yield decreased as the rate of Moddus increased.