Robigus delivers consistently high yields, sets the standard for Septoria resistance and offers proven genetic resistance to Wheat Orange Blossom Midge.

Why Grow Robigus?

Robigus offers growers one of the best options for the first wheat slot in their rotation. With a reliable field performance, Robigus suits a wide range of markets from domestic biscuit making to distilling, feed or export.

· Consistently high yielding 1st wheat

· Accepted Group 3 with biscuit-making, distilling and export quality

· UKS designated and BCE supported

· Resistant to Wheat Orange Blossom Midge

· Industry standard for Septoria spp. resistance

· Robust straw characteristics

· Reliable over all soil types

· Wide sowing window

Its Place in the Market

Robigus is ideally suited to fit the domestic biscuit and distilling market, the export biscuit flour and export blended flour markets (Table 1) and offers growers the security to sell into a wide range of end-markets.

Robigus' very high yield potential ensures that the variety is competitive with Group 4 feed wheat in the UK and export feed markets, providing maximum gross margins.

Yield performance

Robigus performs exceptionally well as a first wheat in all regions of the UK.
In addition, Robigus is extremely flexible and retains its high yield and gross margin potential when grown under a wide range of husbandry regimes and climatic conditions.

Rotational Position

Robigus as a first wheat

Treated and untreated, Robigus is one of the highest yielding recommended winter wheats available. Which ever way you chose to look at HGCA trials Robigus has consistently excelled in the first wheat position.

Robigus as a second wheat

Trials and farm crop observations show that the performance of Robigus as a second or consecutive cereal can be variable and sowing in these rotational positions is therefore not recommended.

Sowing date     

With moderate winter dormancy, Robigus commences spikelet development fairly early in the spring. In regions where winter and early spring temperatures may be relatively warm, very early sowing may result in the developing ear being exposed to late frosts. In this case we recommend Robigus should not be sown before mid September. Where winter and spring temperatures are lower, for example regions north of Lincolnshire, or in fields greater than 150 metres above sea level, the risk is much lower and Robigus may safely be sown from the first week of September onwards.

Robigus performs exceptionally well across a wide sowing window, giving very high yields right through to late December. Because the variety has a low vernalisation requirement, Robigus can be safely sown until the end of February.

Late Sowing

Whether following root crops, fallows to control pernicious weeds, or simply to spread the workload, late sown crops planted after October 6th, accounted for 53% of the winter wheat UK area in 2004/5 and a similar percentage in 2005/6.

Data Source: 2006/7 HGCA/CEL Recommended List

As a moderately fast maturing variety, Robigus performs well when drilled in the late sown, first wheat position (Table 2).

Seed Rates

Whilst seed rates will vary for any given site according to the quality of the seedbed and sowing date, growers should aim to establish an even plant population. The key to maximising yield is to produce an optimum number of ears, 500 to 600 ears/m 2 at harvest.

Suggested seed rates according to sowing date are summarised in Table 3.

Robigus has a relatively strong tillering capacity, producing a high number of primary tillers which are rarely shed, and only a few, small back tillers. Hence when drilling Robigus in September, growers may wish to consider a reduction in seed rates to prevent the development of too dense a crop.

Seed Treatments

Robigus is best suited to a first wheat slot and therefore does not require any additional treatment for take-all. There may be some benefit in regions where disease pressure particularly yellow rust is expected to be high, in using a seed treatment that offers foliar activity to reduce early season risks.

Disease Resistance

Robigus has excellent resistance to the main winter wheat diseases, namely Septoria tritici and Septoria nodorum (Table 4). Robigus also shows excellent resistance to Brown Rust, good resistance to ear diseases and moderate resistance to eyespot.

A programme tailored to the strengths and weaknesses of the variety while maintaining a good degree of robust and broad spectrum activity should be the aim.

Table 4: Disease Resistance of Robigus.

Data source: HGCA/CEL 2006-7 Recommended List

Robigus is susceptible to the ‘Oxbow' race of yellow rust and any fungicide programme should take this into account. Robigus tends to display good juvenile resistance to yellow rust, from first emergence through to flag leaf (Table 4). Whilst some infection can occur in Robigus early in the season, it is unlikely, in all but the highest pressure situations; to develop to serious levels until after the flag leaf has emerged in crops that do not receive any fungicide treatment.

It should be noted mildew infection was identified in a number of crops during the 2004-5 growing season. It is recommended that crops should be monitored during the season and specific mildew treatments included where appropriate.

Wheat Orange Blossom Midge (WOBM)

In the past few seasons WOBM has been a major pest in the UK, particularly in the East and South of England. Known to be responsible for damage to grain quality, WOBM can reduce specific weight and HFN if left untreated.

WOBM over winters in the soil as pupae which emerge when soil and climatic conditions are correct; this usually coincides with ear emergence. Adults lay eggs inside the
glumes as the ear emerges from the boot. These hatch to form larvae that feed on and damage developing grain.

Robigus is the only Group 3 variety and one of only five currently recommended varieties with resistance to WOBM.

Response to Plant Growth Regulators.

Robigus has robust field characteristics and produces very stiff straw (Table 5).

Table 5: Comparative Straw Strength of Robigus.

Nevertheless the variety will benefit from a routine application of chlormequat at Zadoks GS 31 especially in situations where yield expectation is over 10 t/ha.

However, if Robigus is being grown under a high input regime, it is recommended that a structured PGR programme is used to ensure that Robigus reaches its full yield potential. This should include the use of an early season PGR to shorten the lower internodes, followed by a mid/late season PGR to reduce stem length between the middle and upper internodes. The later application has the potential to significantly reduce plant height. This reduces the leverage force acting on the plant's
anchorage system and stem base, thus reducing the risk of both root and stem lodging.

All information is a partial extraction from the Cpb - Twyford's website and also the HGCA Recommended List 2007/8. See www.cpb-twyford.co.uk and also www.hgca.com for the full dataset