Growing cereal rye in Victoria
Rye (Secale cereale) is a comparatively modern cereal, first cultivated in northern Europe. It is thought to have originated from wild types of rye, which are weeds in wheat crops in Asia Minor.
Rye is a winter-spring cereal, with a similar growing period to the main winter-spring cereals, wheat, oats and barley. In Victoria, about 85% of the area sown to rye is in the Mallee region. It's grown mainly for the milling industry — particularly for both the crisp bread and multi-grain bread industry.
The yields can vary greatly from 0.4 to 1.8 tonne per hectare.
Spring rainfall is a major influence on yield in the Mallee as the lighter soils have a low water holding capacity.
Unlike other cereals, rye must be cross pollinated. Often in hot weather much of the pollen dries out before it can fertilise neighbouring plants. The result is that grain does not set properly.
Most varieties of rye require a fairly long period for grain formation. Rye grain can often be small and shrivelled.
Using rye on erosion prone soils
Rye withstands adverse conditions better than other cereals. It can stand cold and limited waterlogging. More importantly, its drought resistance and ability to withstand sand blast enables it to produce a soil-binding cover on land where other cereals will not grow. Under conditions where wheat, oats or barley will grow only a few inches high, or may even be completely blown away, rye often will grow vigorously and reach a height of a metre or more.
A further reason for using cereal rye on erosion prone soils, is the fact that the grain and straw are the least preferred cereal by sheep. Sheep provided with more than one choice of stubble within a paddock will preferentially graze other stubbles before they will eat rye stubble.
After the crop is harvested, the tough, resilient stubble is generally left as a protective cover to reduce blowing of the soil, and to assist colonisation by other species. The stubble of rye breaks up more slowly than the stubble of other cereals, ensuring soil cover for a long period.
Varieties of rye
Although cereal rye has been grown in Australia for more than 150 years, its agronomic development and breeding has been neglected in comparison to other winter-grown cereals. A number of ryecorn strains and selections have been introduced into Victoria at different times. They were referred to by names such as:
- SA rye
- South Australian (SA) Commercial rye
- cereal rye
Although still grown, this variety has largely been replaced by a variety called Bevy.
Bevy was developed at the University of Adelaide from a composite of 9 predominantly semi-dwarf spring rye types. It has increased seedling vigour and superior tillering ability compared to SA Commercial.
Flowering about 2 weeks later than SA Commercial, Bevy is less prone to frost which often affected yields of the SA Commercial variety. It is well adapted to Mallee environments and has performed far better than SA Commercial in longer growing seasons.
Bevy is a composite of mostly (80%) semi-dwarf plants with 15% of plants as tall as SA Commercial and 5% being very short. When mature, heads also range in length.
Resistance to cereal cyst nematode (Heterodera avenae) and a poor host to root lesion nematode (pratylenchus neglectus) means rye can be useful to manage these diseases. Bevy however is a host for the root disease take-all (Gaeumannomyces graminis) and this should be carefully monitored.
Rye for grain is sown at the same time as wheat, oats or barley (May or June), although it is often sown first as rapid ground cover is normally desirable on the soils where it is sown. Seeding rate should be between 40 to 50kg per hectare or aiming for between 140 and 160 seeds per square metre. A smaller seed size than wheat, Bevy rye should be sown shallower, not exceeding 2 to 2.5cm in heavy soils and 3.5 to 4.5cm in sands.
Its root system branches extensively in the first 300mm of soil. This is a major reason why rye is more drought resistant and does better on poorer soils than wheat. The well developed root system allows it to quickly produce a large bulk of early green feed which has a nutritive value comparable with other cereals.
If seasonal conditions are unfavourable for pasture growth in the Mallee, cereal rye is often sown dry during March for green feed. The sowing rate should be increased to 80 to l00 kg per hectare to maximise fodder production. Graze when plants are 150mm high and tillering. The later stages of growth are stemmy and unpalatable to stock. Cereal rye is generally not a suitable hay crop.
For the purposes of green manure cereal rye can be sown February or March or as late as August in high rainfall areas.
Phosphorus fertiliser and, where necessary, nitrogen fertiliser are recommended in the same amounts as recommended for wheat. The current recommendations for the Mallee are:
- phosphorus at 10 to 15 kg per hectare and 10 to 20 kg per hectare of nitrogen applied at sowing
- occasionally nitrogen broadcast post sowing may be required if the crop appears deficient
Although rye comes into ear earlier than wheat, the grain takes much longer to mature. The crop should be harvested as soon as the grain is thoroughly dry and hard. Seed losses due to shattering can occur soon after it ripens.
Rye is harvested with a conventional header. The grain is lighter and longer than wheat, so the machine will require minor adjustments from normal wheat settings.
Pests and diseases of rye
Rye in the paddock is generally free from insect pests. Where problems arise, growers should contact their local agronomist or Agriculture Victoria for advice.
Cereal rye grain does not store well unless frequently treated for insect contamination. To minimise insect attack, the grain should be stored at less than 10% cent moisture, preferably in sealed silos. Treat the grain as it enters the silo and then check regularly (2 to 3 months) for reinfestation by grain insects.
The most important disease of rye is ergot (Claviceps purpurea). This is not generally a problem in the Victorian Mallee. Nevertheless, it is important to realise that feeding stock with ergot infested grain can result in serious losses. Stem and leaf rusts can usually be seen on cereal rye in most years but they are only occasionally a serious problem.
Rye grain is smaller and darker than wheat, is harder to mill and produces a lower percentage of flour.
Hectolitre weight is normally about 70 to 75kg, with a minimum of 70 kg per hectolitre and maximum moisture of 12% for marketing purposes.
Grain protein tends to be slightly lower than that of wheat. The dough lacks the elastic properties of wheaten dough. Bread made from rye flour has a close texture and a distinctive taste.
Demand for rye
Local use for rye is mainly in the form of kibbled rye or cracked grain for use in mixed grain breads or for breads requiring more fibre. Demand has also increased for sour-dough rye bread, rye flour and rye meal.
Production in Australia is generally erratic, with supply and demand very elastic and price sensitive. Seasonal conditions and the soil type and topography where rye is usually grown greatly influence seasonal production. Supply shortfalls are usually met by the importation of grain from Canada.
Grain buyers or merchants purchase cereal rye and growers are advised to explore their available options before committing to producing cereal rye. Prices fluctuate according to supply and demand.