Average rainfall in most districts of SA during April and May last year, provided the opportunity for timely sowing of the SA NVT triticale program. Seven trials were sown during mid to late May, with only one site at Turretfield sown in early June. Good follow up rains were received in most regions in July and August, but these conditions were short lived, as a very dry spring was experienced in all areas.
While the triticale National Variety Trials were sown at eight sites across South Australia in 2008, two of these sites failed to produced useful results due to either severe drought stress or high variability across the site. Under these weather conditions, the state-wide triticale trial yields were considerably lower than anticipated, with only trials at Frances and Turretfield reaching their yield potentials based on the growing season rainfall (April to October) in 2008.
Site average yields ranged from 0.4 t/ha at Wharminda to 5.8 t/ha at Frances. Yields across the low rainfall sites reflected the poor spring rainfall with the Pinnaroo and Minnipa sites receiving only 166 mm and 139 mm respectively during the growing season. High rainfall sites at Frances and Turretfield received rainfall of 348 mm and 251 mm respectively for the same period. The dominant yield limiting factor across all sites was the limited rainfall received in spring.
The new variety Bogong was the overall top yielding triticale variety across the SA trials. Bogong was top ranking at three of six sites, and second highest yielding at two sites. Across all six sites it averaged 15 percent higher than Tahara. Bogong (tested as H127) was released by the University of New England, Armidale in 2008 It is an early to mid season flowering (similar to Treat) fully awned, stiff strawed, grain variety with good resistance to all common field strains of rust. Bogong has not been tested for CCN resistance but is unlikely to show resistance. No long term yields are available as Bogong has not been widely evaluated across seasons within SA NVT and further evaluation is needed.
Two other new varieties that also performed well in the 2008 trials were Canobolas and Hawkeye. These two new varieties performed similarly on average, with Canobolas being in the top three varieties at four of the six sites and Hawkeye at three sites. Across sites, Canobolas averaged 16 percent higher than Tahara in the high and medium rainfall sites while at the lower rainfall sites, Minnipa and Pinnaroo, it was out-yielded by Tahara. Canobolas is an awned, stiff strawed, early to mid season grain variety that is 1-2 days faster than Everest and Treat. It has good resistance to all common field strains of rust. Canobolas has shown acid soil tolerance and is therefore suitable for areas with acid soil symptoms. No long term yields are available, as Canobolas has not been widely evaluated across seasons within SA NVT and further evaluation is needed.
Hawkeye averaged 6 percent above Tahara’s yield across all six sites. Long term (2000 – 2008) yields show Hawkeye ranges from 4 to 13 percent above Taraha’s yield with a state average of 8 percent. Hawkeye (tested as TSA0108) was released by AGT in 2007 and is a broadly adapted, mid maturing variety with high yield potential and CCN resistance. It also has good resistance to all rusts and produces large grain with low screenings (like Tahara) and good test weight (like Treat). It is considered a higher yielding alternative to Tahara and a CCN and stripe rust resistant alternative to Kosciuszko.
In the 2008 trials, Jaywick was on average 5 percent higher yielding that Tahara at four of the six sites. Jaywick’s long term yields range from 2 to 12 percent above Taraha’s yield with a state average of 7 percent. Jaywick (tested as TSA0124) was released by AGT in 2007 and is a broadly adapted, early to mid maturing variety with high yield potential, especially in short, dry seasons. It also has good resistance to all rusts and CCN resistance and produces large grain with low screenings (like Speedee) and good test weight (better than Speedee). It is considered a higher yielding, CCN and stripe rust resistant alternative to Speedee, suited to shorter seasoned environments or a later planting option.
Compared to Tahara, Rufus was on average 6 percent higher yielding across five of the six sites. Its long term yields range from 98 to 103 percent of Taraha’s yield with a state average of 102 percent. Rufus, a non PBR variety, was released by the University of New England in 2005. Rufus is a tall, midseason maturity, CCN-resistant variety with wide adaptation. Trial results indicate Rufus to be a useful grain variety, but with features such as reduced awn length, good early vigour and height, there is strong interest in it as a hay or dual purpose variety. Rufus is 2-3 days earlier than Tahara and is about 5 cm taller and lodging may be a problem in very high rainfall situations. Grain yields at low rainfall SA sites have been shown to equal Tahara but it shows superior yields in trials in higher rainfall districts. The University of New England released Rufus after interest by SA growers as a dual purpose or hay type.
Speedee was the top yielding variety at the two low rainfall sites, Minnipa and Pinnaroo, yielding 35 percent and 27 percent above Tahara respectively. Speedee’s long terms yields range from 93 to 102 percent of Taraha’s yield with a state average of 99 percent. Speedee (tested as TX93-19-1E) is a fast growing and early maturing variety, released in 2003. It heads about 10 days earlier than Tickit and Tahara, making it a suitable variety choice for short growing season environments or late sowing situations. It is not resistant to CCN.
Tahara has been the generally preferred triticale variety for use in cereal rotations in most districts up to 500 mm average annual rainfall. Its good resistance to CCN and root lesion nematode (Pratylenchus neglectus) make it a valuable disease break. Lodging can be a problem in wetter areas or higher yielding situations. Certified seed is not available, so must be purchased from other commercial growers. Crops to be used for seed should be inspected for weed and other cereal crop contamination, and provided with good nutrition to ensure high quality seed.
Across five of the six NVT sites Tickit was on average 5 percent higher yielding than Tahara. Its long term yields ranged from 99 to 103 percent of Taraha’s yield with a state average of 101 percent. Tickit was released by the University of Adelaide triticale breeding program in 2002. It is expected to replace Tahara, having similar disease resistances, including resistance to CCN, Pratylenchus, and stem, leaf and stripe rusts. It is slightly shorter than Tahara and has stiffer straw.
Treat was on average 8 percent higher yielding than Tahara across the state, except at Wharminda where it yielded 4 percent lower than Tahara. Its long term yields range from 93 to 101 percent of Taraha’s yield with a state average of 98 percent. Treat is a medium-season grain triticale, several days earlier maturing than Tahara. Its major advantage is superior seed quality: test weight about 6 kg/hl above Tahara, and smoother appearance. This should increase the likelihood of achieving receival standards in districts where test weights are often too low.
