Take Home Messages
- Sunmaster, Sunblade CL Plus and Beckom were the highest yielding varieties in 2022 in the Mallee and were 10 per cent above the region mean.
- In the North Central region, Sunblade CL Plus, Sunmaster and RGT Zanzibar were the highest yielding in 2022.
- Long-term yield data suggests Vixen, Rockstar, Scepter, Catapult and Beckom have yielded higher than the region mean over the past six years in the Mallee.
- Calibre, Rockstar, Ballista, Brumby, Scepter and Vixen were the highest yielding varieties long term (2017–2021) as a percentage of region mean in the Wimmera.
- Sunmaster, Brumby and Reilly are new varieties worthy of consideration in the future
Aim
To compare the performance of new and existing wheat varieties in the Mallee, North Central and Wimmera NVT.Â
Background
Varieties are constantly changing as breeding brings new varieties into the market. Choosing which varieties to grow is an area many growers find difficult each year; asking ‘Am I growing the best variety, or should I be changing?’. On occasions the variety is not the problem, when time of sowing and overall management have major impacts on final grain yield.
Many growers are considering introducing alternative varieties for the 2023 season, given the high disease exposure risk from some commonly grown varieties, such as stripe rust in Scepter wheat.
Choosing a wheat variety is an ongoing process, with many growers chasing the most rust resistant variety. However the presence of a green bridge over summer, rotation, in-season management and the season itself, often play a bigger role in disease levels. Consider how often we see a decile 10 season. Selecting multiple maturity length varieties is also crucial for spreading risk and management on farm.Â
Trial Details
Crop type: Wheat
Target plant density: 130 plants/m²
Seeding equipment: Knife points, press wheels, 30cm row spacing
Nutrition, weeds, insects and disease were managed as per best practice.
The early break trial at Birchip was dry sown and received 16mm rain on 19 April.
Method
This research was conducted through the NVT program delivered by the GRDC. The NVT program involves a series of replicated field trials that test varieties across 10 crop types. The data displayed in this article is a combination of NVT results, individual site reports and multi-environment trial analysis (MET) long term summaries. The MET analysis should be used by growers when comparing varieties as this encompasses more data over multiple seasons and is therefore more reliable. Both the MET analyses and single site summaries can be found at nvtonline.com.au. Grain yield data is represented as a percentage of the site mean for the past five years, which shows how a variety has performed in each season compared with the region’s overall mean yield.
Results & Interpretation
New varieties released in 2022
Brumby is suited to M-HRZ and is resistant to powdery mildew. An APW wheat suited to early May sowing. Maturity between Rockstar and Scepter. MR for stripe rust, MR for stem and MR for CCN, it is best suited to powdery mildew areas. It was bred and marketed by InterGrain.
Kingston is an AH variety released in 2022 and is a mid-maturity variety, compact plant type, bred by BASF and marketed by Seednet.
LRPB Anvil CL Plus is AH quality, suited to low to medium rainfall environments, quick maturing with tolerance to label rates of Intervix®. Bred by GIA, developed by LongReach and marketed by Pacific Seeds.
Reilly is suited to low to medium rainfall environments, with AH quality, mid maturity and medium plant height. Bred by BASF and marketed by Seednet.
Yield results
Overall site averages of 4.7t/ha were recorded across the Mallee, ranging from 4.3t/ha at Birchip to 5.5t/ha at Ultima. The Birchip early break trial (long season wheats) had an average yield of 4.49t/ha. In the North Central an average of 6.1t/ha was achieved between Charlton and Diggora sites (Table 2)
In the Mallee, Sunmaster, Sunblade CL Plus and Beckom were the highest yielding varieties in 2022 across all Mallee sites and were above 110 per cent of the region mean (Figure 1). All three are mid maturing varieties. The long-term data has shown Calibre, Vixen, Rockstar, Brumby and Scepter have all consistently yielded higher than the average region mean. Keep in mind Brumby has only been in the physical NVT trials for two years and the remaining years of data are predicted yields.
Sunblade CL Plus, Sunmaster and RGT Zanzibar were the highest yielding in 2022 in the North Central region (Figure 2). RGT Zanzibar is RMR for stripe rust and despite being a feed wheat yielded 35 per cent higher than the region mean. Others to note include Beckom, Ballista, LRPB Scout, Cosmick, Reilly and Rockstar which all yielded above the region mean in 2022. Looking at the long term data from 2017, 2019–2021 (no data from 2018) there are 19 varieties which are all higher than the region mean. These include Vixen, Ballista, Calibre, Scepter, Boree, Rockstar, Brumby, LRPB Anvil CL Plus and Catapult. Chief CL Plus did not yield well in 2022, reflecting the presence of disease, as it is SVS to stripe rust.
Calibre, Rockstar, Ballista, Brumby, Scepter and Vixen were the highest yielding varieties long term (2017–2021) as a percentage of region mean in the Wimmera. In 2022 Sunmaster, Sunblade CL Plus, Rockstar, Cutlass and Valiant CL Plus all yielded higher than the region mean
When comparing the percentage region mean of six varieties across seasons, they performed differently in various years. Scepter yielded lower than the mean in 2022 but performed well in the previous five years (Figure 4). Vixen performed well in 2019 which was a decile 3 for many areas of the Mallee. This highlights how seasonal conditions such as disease, can have an impact on final grain yield. For comparison, when looking at how Scepter performed in NVT 2016 (a decile 10 GSR) it was anywhere from 5–8 per cent higher than the region means in the Mallee (data not shown).
In 2022 fungicide management and disease profile played a big part in grain yield. We saw varieties that have done consistently well during the past few years perform poorly. This was mostly not related to yield potential but rather disease management, particularly in a wet spring (Table 3). All trials in the NVT were managed for disease and it is often unknown if there are recurrent infections from susceptible varieties in small plots. Growers faced the same challenges in 2022, in such a high-pressure disease situation. Scepter has been a commonly grown variety, however each year there are new varieties released with greater yield potential. It is worthwhile assessing all aspects of a new variety before changing after just one season. Table 3 highlights some of the differences in commonly grown varieties and new releases. Consider where in your rotation that you grow wheat ie. if you grow Reilly on a vetch stubble then YLS (while it is susceptible) will be less of a problem. If you are wanting an alternative to Scepter, then consider which options you may choose and what the trade-offs are for selecting another variety with greater stripe rust resistance.
Anecdotal evidence from 2022 showed that for many growers where disease was managed in Scepter, grain yield was not affected and in some cases — with four fungicide applications — it topped grain yields. In such a high disease year there may also have been diseases other than stripe rust affecting grain yield. Consider the cost associated with achieving four fungicide applications as well as the time, labour commitment and frequency of these seasonal conditions.
Commercial Practice and On Farm Profitability
In a season with a decile 10 GSR, high spring rainfall and an elongated grain filling period, disease was a big factor in wheat yields in 2022. While these conditions will not be experienced every year, it is important to understand variety choices and management when the forecast of a high rainfall year is upon us.
If selecting an alternative to Scepter, consider including a second variety in your rotation where you can spread your risk as well as lessen the management (spraying) pressure. Consider Sunmaster, Beckom or Reilly which are MRMS for stripe rust as a second variety on farm , not as a whole program replacement, but to mitigate risk by having part of the program with a slightly better rating, allowing for a wider spraying window.
In the North Central it is a similar situation to the Mallee in terms of selecting an additional variety. Choose a variety that has been a consistent performer for a few years and has the characteristics that suit your rotation or can be managed in a timely manner.
Given the expression of so many diseases, it will be important to ensure clean seed is sourced for the 2023 sowing program. Going into the 2023 season it is important to have seed tested if there’s any chance it may carry over disease, such as white grain disorder or fusarium. High soil moisture levels will also be present in many regions and there will be a green bridge to consider.
References
Victorian Crop Sowing Guide, 2023, Agriculture Victoria, https://grdc.com.au/resources-andpublications/all-publications/nvt-crop-sowing-guides/vic-tas-crop-sowing-guide.
GRDC National Variety Trials yield data, 2022, https://www.nvtonline.com.au.
Acknowledgements
This research was funded by the GRDC as part of the ‘National Variety Trials’ project (BWD00029). This summary has been funded by BCG members through their membership.
