5 September 1997

WIDER OPTIONS FOR LATE WHEAT

WITH a heavy sugar beet crop in prospect selecting the most appropriate wheat variety for sowing after late harvested roots could be more important than usual this year.

Last seasons protracted beet processing campaign saw many growers leave crops in the ground rather than lose sugar in clamps. That could happen again forcing more late wheat sowings. But this time wheat growers expect next seasons grain prices to be low, so yield and marketability will be more important than ever.

"Traditionally late autumn drilled wheats have been bread-making or spring varieties used in the alternative wheat role. But that could change," says NIABs cereals specialist Richard Fenwick. "Growers now need both high yield and some added-value quality."

Yields vary

Some of the usual high yielding feed-only types can do well in the late slot and may be used depending upon what is left over from earlier drillings. But yield performance later in the season is not the same, as it is earlier, Mr Fenwick stresses.

"In our Cereal Variety Handbook November-drilled Hussar has a yield score of 112 compared with Brigadiers 111, the same as the spring type Chablis, which has the bonus of some quality. Rialto and Charger, both added value varieties, have also done well at late drillings.

"Riband has performed reasonably well but not up to the levels of Brigadier and Hussar. Hereward has not done as well as Chablis, Charger or Rialto, but the yield gap is reduced compared with earlier sowings and it could still be used by growers wanting best possible quality."

Standing power for late drilling after beet, cereals or linseed is less important than after heavily fertilised rape or potatoes. Spring varieties tend to be more prone to lodging when sown in the autumn than true winter types, but Shiraz, Axona and Avans all have a similar lodging score in NIAB trials, notes Mr Fenwick.

Where residual N levels are reasonable later sown crops stand better than early sowings, so less chemical help is needed to keep them on their feet.

Disease resistance is also less important as the risk, particularly from Septoria, tails off with the approach of winter. But later-sown wheat is more prone to mildew in the spring.

According to Doug Stevens, senior agronomist at Morley Research Centre in Norfolk, good tillering ability is valuable in late sown wheat.

"Hussar tillers readily and was a good option in the past, but it is now challenged by Charger, which matches it for yield but with some quality," he points out.

"Chargers weakness is its standing power when sown early, but this is not a problem later on. As the spring type Chablis does not have super bread-making quality, it is probably an option because of its high yield. On the NIAB list it out-yields Brigadier at the November sowing."

Late wheat can be grown more cheaply than an earlier sown crop, he adds. There are potential savings to be had from less fungicide, growth regulator and nitrogen, as disease pressures are less and yield expectations lower.

"It is possible to reduce the amount of N applied by 30kg/t of expected yield, and, as late crops are likely to yield about 1.5t/ha less, the rate could be cut by 45kg/ha. But this is offset by the need for more seed. Target establishment for October-sown wheat is 200 – 250 plants/sq m. More difficult conditions in November mean 25% more seed is needed to hit the higher target of 275 – 300 plants to compensate for reduced tillering," says Mr Stevens.n

Late beet harvesting (above) to meet late delivery permits while avoiding hefty clamp losses could mean more late wheat sowing this season (left). New variety options give gowers more choice than usual, says NIAB.

LATE DRILLING

&#8226 Aim for yield and quality.

&#8226 Chablis, Charger and Rialto good.

&#8226 Scope to cut inputs, but watch drilling rates.

&#8226 Spring malting barley valuable alternative?