27 March 1998

Pgr economy bad

DONT cut back on pgr when looking to reduce production costs. Crops are generally very lush and therefore more prone to lodging than usual, so far more could be lost than gained by foregoing preventative measures, says Dr David Ellerton, technical director at ProCam Agriculture.

"Many wheat crops are very thick with an average of six to eight tillers/plant compared with the normal three or four," says Dr Ellerton.

It might pay to go in closer to GS31 than 30, he suggests. By contrast a late growth regulator, which a large proportion of crops will also need, could benefit from a relatively early dose at GS33 to avoid a repeat of last years missed applications when the weather turned dry.

The lusher crops will need a good second hit to strengthen the top internodes, says Dr Ellerton. "We must avoid what happened last year when we waited until GS37 and got caught out by the very dry conditions. Crops were under moisture stress as a result and so we had to forego that treatment.

Morley Research Centre trials last year echo the need to avoid inappropriate pgr cuts.

Growth regulator trials with the relatively weak strawed wheat, Reaper, gave a top yield response of just over 2tha (0.8t/acre), worth nearly six times the £27.50/ha (£11.13/acre) spent on keeping the variety standing using a sequence of 1.5litres/ha of New 5C Cycocel at GS30, another 1.0l/ha at early GS31, then 1.5l/ha of Terpal at GS37.