10 April 1998

New pgr to crack lodging

LODGING risk could be high this year and susceptible crops will require a late season plant growth regulator. A new product launched this month could help.

Dense, well established crops on moist soils, with high mineral N, are prime lodging sites, says John Spink of ADAS Rosemaund. "Crops this season have grown and established in a way which will produce a high lodging risk."

Three factors influence this risk says Mr Spink. Leverage force on the crop, the stem strength, and anchorage. "Growers should consider each individual process when assessing lodging risk."

"Almost all of the damage in 1997 was due to anchorage failure," he suggests.

Wind and rain after ear emergence are the usual conditions associated with crops going down. But weather in May is just as important.

Cool, bright conditions at stem extension cause long inter-nodes, especially in thick crops. "If it is cool and bright during stem extension, then growers should seriously think about a late-season pgr rather than relying on what was done in March," he stresses.

This GS 32-39 window is where Cyanamid targets new pgr Satellite. Containing 540g chlormequat, 270g ethephon and 2g imazaquin in a hectare pack, the manufacturer claims it shortens upper inter-node length more and is safer than other products or tank-mixes of its constituents.

Trialing the product last season, distributor Willmot Pertwee reduced the height of Reaper by 10cm (4in) and increased yield by 0.9t/ha. "It was the most effective treatment," says Chris Bean, technical director. No treated area lodged, compared to 34% of the untreated crop. Specific weight was 3.5% higher too.

Similar results were seen in barley on heavy soils in Lincolnshire. Across 11 trials, mean yield increase was 0.94t on an untreated crop of 7.21t/ha. The standard chlormequat followed by Terpal (ethephon + mepiquat chloride) produced 0.56t/ha over untreated.

Cyanamid attributes increased efficacy of the product to the positive interaction of imazaquin with the other actives.

However, Dick Neale of distributor Hutchinsons is unconvinced. "Weve been unable to make Meteor, which contains imazaquin, chlormequat and choline chloride, give any better lodging control than straight chlormequat. We dont see why this product is any different."

But both Mr Bean and Mr Neale agree on the lodging risk this season. "There is no way a single application will do the job. It is definitely a year to split applications every 14-21 days to keep a hold on crops," says Mr Neale.

Mr Bean says "We will recommend late pgr use on high lodging risk crops, both wheat and barley, and there could be quite a few of those." He suggests a two-thirds rate of Satellite at GS 32-33 in wheat and GS 37 in barley.

Approved by the Brewers and Licensed Retailers Association, the new product can be used on spring as well as winter barley.

Packed in a twin-pack containing 3.06 litres of product, Cyanamid say it will be priced at about £24/ha (£10/ha). &#42

Consort wheat going flat in March, a warning of high lodging risk in many cereals this season, says John Spink of ADAS Rosemaund.

NEW PGR

&#8226 New late season pgr.

&#8226 Many high lodging risk crops.

&#8226 Greater efficacy and safety claims.