Independent variety testing, funded by the Grains Research and Development Corporation shows recently released wheat varieties yield better than their predecessors and have better disease resistance.
Comparisons in this analysis are based on trials conducted between 2012 and 2016, a combination of very dry and very good seasons. Flanker for example, released in 2015, in early sown trials has in the northern half of NSW yielded about 108 per cent of mean site yield and 106pc in main season sown trials.
Flanker is an Australian Prime Hard (APH) quality variety with mid to slower maturity similar to Gregory and suited to sowing in many areas from about April 20.
It tends to be four to eight per cent higher yielding than Gregory (2004 release).
Older varieties in this maturity group have yielded even further behind Flanker.
For example Strzelecki (2000) yielded about 95pc of mean, and Sunbri (1990) about 90pc of mean.
Coolah (2016), another high yielding variety released for sowing from late April has on average yielded 110pc of mean site yields.
It is also APH quality, has excellent resistance to the three rusts and also, importantly for many growers, has useful tolerance to root lesion nematodes (P. thornei).
Sunmax (2015), a APH slow-maturing spring wheat suited to sowing from about April 10 has yielded about 10pc better than Sunbrook (1995), a similar maturing line.
Kittyhawk (2016) is another important new variety, being a fully rust resistant winter wheat. Suntime (2015), also a APH variety has yielded about 101pc mean yield. Its slower maturity is more a comparison with Sunzell (2006) that has a mean trial yield of about 90pc.
Suntime is also more disease resistant. Mitch (2014) suits sowing from about April 20 and has also yielded well overall (about 109pc of mean).
Like several of the slower-maturing varieties detailed above it has also shown good versatility and yielded well overall in the main season sown trials.
The examples of improvement in slower-maturing varieties are important, as several major research projects have shown the importance of earlier sowing. Earlier sowing with slower-maturing varieties when possible commonly yields 20pc or more than later sowing, even with quicker maturing varieties. In the broad group of varieties categorised as “main season” sowing, several new releases have improved yield.
In the 2012-2016 trial analysis Reliant (2016) rates about 107pc, 10pc ahead of once-popular Crusader (2007).
Reliant also has improved disease resistance, is APH quality in northern NSW but Australian Hard (AH) in southern NSW.
Condo (2014) especially suits western areas and later sowings and has yielded on average about 106pc of mean. Sunmate (2014), an APH variety, has one of the best tolerances to root lesion nematodes (P. thornei). It has yielded about 104pc and suits sowing from May 20 onwards.
Suntop (2012), also APH, with yield about 105pc suits May 7 onwards sowing.
Some of the high yielding group may have low rankings for one or more of the rust diseases and require planned strategies to reduce risk. For example seed treatment, in-crop fungicide use when trigger disease levels occur.
In some situations best tolerance to nematodes or diseases like yellow leaf spot can be considered important.
Acid soil tolerance is an advantage in some soils. Not all high yielding varieties have been covered in this short summary.
Full details available in the NSW DPI Winter Crop Variety Sowing Guide.
Next week: Tropical grasses plus winter legumes suit most of NSW.
- Bob Freebairn is an agricultural consultant based at Coonabarabran. Email robert.freebairn@bigpond.com or contact (0428) 752 149.