How did last year’s cereals PGR introduction, Canopy, measure up. Louise Impey finds out
“Our trials confirm Canopy fits in with the little-but-often PGR approach we use,” he says. “We favour three applications, as it means the crop gets a targeted dose each time, rather than putting it all on in one hit and risking crop shock.”
The Hutchinsons’ work compared PGR rates to give more detail into how the different products should be used, he says. “We now know that 0.1 litre/ha of Moddus is equivalent to 0.3 litre/ha of Canopy, while 0.2 litre/ha of Moddus is the same as 0.6 litre/ha of Canopy.”
Mr Neale recorded identical results from the two PGRs when the appropriate dose rate was used giving him confidence to recommend Canopy in exactly the same way as Moddus.
“Of course, growers will always have to tweak what they do, according to the season and the state of the crops,” he notes.
Using PGRs is like buying insurance, believes Mr Neale. “You don’t know what’s going to happen at the time of application. But to avoid lodging you must spray at the right time you can’t pull a crop back once the timing has passed.”
Three PGR applications, made at GS30-31, GS32 and GS39, gave both the best lodging control and the highest yield in trials last year. “A programme always performs better than using a single dose of PGR.”
The only surprise with Canopy last year was the appearance of some adverse crop effects, even at low doses. “But given the year and the conditions we experienced it was only to be expected. We knew it could happen with Moddus and Canopy is a similar product.”
The prolonged dry spell in April was not ideal for growth regulator applications, he admits. “But we weren’t on light sandy soil and the dose was reduced down to 0.6 litre/ha to compensate for the conditions.”
Nevertheless, some overgrowth regulation and leaf scorching occurred. “It was a surprise, but so was the year. We’ve used Canopy before right up to the maximum dose of 1.5 litres/ha, without seeing anything unusual.”
In barley Canopy must be used on its own, Mr Neale advises. “Cycocel detracts from it in barley. And in both wheat and barley, you should use Exchange water conditioner. It gives a significant improvement in its effectiveness.”
Independent agronomist Steve Harrison also looked at Canopy last year, comparing it with Moddus and opting to test it in an extremely high lodging risk situation.
“It was applied to a crop of Robigus on heavy land, which had received sewage sludge the previous autumn. It had lots of lush, leafy growth with high shoot and tiller numbers,” he comments.
Mr Harrison substituted Canopy into the second PGR timing at GS32 in place of Moddus, adding it to 5C Cycocel and mixing it with the T1 fungicide. Earlier at GS30-31 the crop was treated with 0.2 litre/ha Moddus + 1.25 litre/ha 5C Cycocel.
“It was extremely dry, so the product wasn’t widely used,” he says. “But in this case, it did exactly what we were expecting. Once it did start to rain the crops grew like mad, but this one was held in check. We didn’t need to put any Terpal in with the flag leaf spray.”
Canopy was easy to use and mixed well with fungicides, he says. “It also showed us that you can substitute Moddus for Canopy and vice versa, without any problem.”
Mr Harrison adds that Canopy is best mixed with chlormequat, or the costs rise considerably. “Considering that chlormequat supply is likely to be limited this year, it’s useful to know that there are other products around. We’ll be checking the pricing of Canopy against Moddus before making any final decisions.”
Canopy v Moddus
- Products interchangeable
- Programme approach favourable
- Mix with chlormequat in wheat
- Use alone on barley
- Canopy – prohexadione-calcium + mepiquat chloride
- Moddus – trinexapac-ethyl
- 5C Cycocel – chlormequat