PBA Bolt is a good first choice for Esperance lentil growers, with PBA Ace an option for early sowing or longer seasons. The new XT line CIPAL1422 performed well and may be a valuable alternative to PBA Hurricane XT for those growers wishing to use imazethapyr (e.g. Spinnaker^®) or facing SU carryover issues.

PBA Samira was the highest yielding released faba bean variety at Wittenoom Hills.

• Agronomic management of canola changes considerably when sowing very early.
• There was a large yield benefit from establishing canola in mid-vs late April of approximately 40 kg/ha/day but the additional benefit of sowing in late March vs mid-April was only about 10 kg/ha/day.
• Climatic and agronomic risks increase with early sowing.

• At Grass Patch in 2016 there was no response to fertiliser applications of K, S and micro nutrients. 
• There was a yield response to P and N.
• Considering the costs of inputs, the lowest cost treatment which provided equal maximum gross margin was to apply only superphosphate at sowing – equivalent to 9 kg P/ha.
• In this region farmers typically apply either superphosphate plus N or a compound fertiliser at sowing and top-up N at 4- 6 weeks after sowing.  This approach in this experiment would have had higher up front input costs, did increase yield but did not lead to higher gross margins.  But the farmer approach also is a more balanced nutrient approach, in that nutrients are replaced to balance out nutrients removed in the seed.

• Green peach aphid feeding damage to flowering canola did not cause yield loss.
• Canola seed oil content also was not correlated to population density of green peach aphids.
• Applying insecticides to control feeding damage in the absence of virus may be of little benefit and increase the rate of insecticide resistance.

• New varieties have improved ascochyta resistance, but still need careful management.
• Avoiding early infection is critical to managing ascochyta effectively.
• A two spray fungicide strategy will provide reliable control.

Farmers can safely retain OP seed for at least two years

Retained and graded hybrid TT seed had lower % establishment, variability in flowering, higher % of sterile flowers, lower oil and yield – but in this environment with yields below 1.5 t/ha the effects were not large enough to reduce gross margins compared to purchasing hybrid TT seed.

Farmers can safely retain OP seed for at least two years

Retained and graded hybrid TT seed had lower % establishment, variability in flowering, higher % of sterile flowers, lower oil and yield – but in this environment with yields below 1.5 t/ha the effects were not large enough to reduce gross margins compared to purchasing hybrid TT seed.

• Even when sowing in April, into drying soil, establishment of canola was better at 1 cm compared to 3 or 7 cm.
• Sowing small OP seed deeper, at 3 and 7 cm, resulted in the poorest establishment and yield.
• In difficult conditions hybrid seed was better able to establish than OP canola.

• Even when sowing in April, into drying soil, establishment of canola was better at 1 cm compared to 3 or 7 cm.
• Sowing small OP seed deeper, at 3 and 7 cm, resulted in the poorest establishment and yield.
• In difficult conditions hybrid seed was better able to establish than OP canola.

• There was a trend of more yield from evenly spaced plants compared to unevenly spaced plants with a 5% improvment at lower plant densities, however this was not statistically significant.
• Spacing plants more evenly did affect some aspects of plants growth.
• Canola yields were above 2.5t/ha from low plant density, 10 plants per square metre

Previous research has shown good snail control comes from snails being able to come across baits and feed on them. The more even the bait distribution, the more likely the snails will come across a bait, feed on it and die.

It is becoming more common to apply baits aerially, but there have been no previous studies on the distribution of baits applied from aircraft.

In this study, we found the distribution of baits varied depending on the distance from the flight path of the plane and that bait application swath widths of the plane needed to be 15 metres rather than 30 metres. This trial highlighted that better calibration techniques are needed for aerially applied bait applications.

• Early sowing is the key to maximising canola yield in the northern region;
• Delaying sowing by 15 days after March 31 led to 195kg/ha less yield – a loss of 13kg/ha/day.
• When sowing in March at Wongan Hills the mid and mid/late maturity varieties performed best.
• When sowing in mid-April early and early/mid maturity varieties performed best.

Windrow burning can reduce small pointed snail populations by over 90%. If there are weeds or fallen stubble that are not burnt then snails can still be present in the paddock.

Windrow burning can reduce small pointed snail populations by over 90%. If there are weeds or fallen stubble that are not burnt then snails can still be present in the paddock.

• Agronomic management of canola changes considerably when sowing very early.
• There was a large yield benefit from establishing canola in mid-vs late April of approximately 40 kg/ha/day but the additional benefit of sowing in late March vs mid-April was only about 10 kg/ha/day.
• Climatic and agronomic risks increase with early sowing.

• Across the trial series at Grass Patch, Ballidu, Merredin and Holt Rock the highest grain yields, oil and gross margins were from the open pollinated variety, so growers should continue to use open pollinated TT varieties in the low rainfall regions, rather than hybrid varieties.
• In the hybrid treatments, there were generally increased yields and oil from the purchased (F1) seed, compared with the retained (F2) seed.  The gross margin was only significantly better at the Grass Patch site, for the 2014 F1 compared with the retained seed. Grading to increase seed size and sowing at a target density of 40 plants/m² improved the yield and gross margins of F2 retained hybrid seed, but at Grass Patch in 2015 using F1 hybrid seed or OP seed provided better results..

• Early sowing is the key to maximising canola yield in the Northern Agricultural Region (NAR)
• All varieties yielded less when sown on April 29 compared to April 14.
• Yield loss was on average 43 kg/ha per day between April 14 and April 29 sowing.
• Using the highest yielding variety rather than trying to match variety maturity to sowing date was the best option.

• The Podguard line AN14R9012 appears to be a viable option for direct harvesting and delayed harvesting of canola.It does not appear to shed seeds from pods to the same degree as other varieties.
• Under extreme conditions AN14R9012 can drop whole unopened pods and therefore lose yield.

Canola Grain Yield at Pindar

All varieties apart from Stingray were able to yield the same or higher from the 9th April sowing opportunity.

As expected the shorter seasoned varieties were not able to capitalise on the 9th April sowing as the longer season varieties.    Grain yield declined with delayed sowing for longer season canola varieties.

Growers may not see a flat yield response for early sowings as an issue.  Instead, the early sowing window allows them to get crop out of the ground and reduces the risk of dry spells leading to a lack of future sowing opportunities.   However pests (eg Diamondback moth) and diseases (such as Sclerotinia), depending on rainfall zone and soil type, need to be factored into decisions about very early sowing windows.

The success of very early sowing depends heavily on soil type, soil moisture and temperature. Growers need to assess the conditions they face in the lead into each season closely before embarking on very early sowing, especially when using hybrid seed with high seed costs.

• Forrest was the highest yielding variety for the 9 April sowing date (Table 6). Shorter season varieties were not able to capture the yield benefits of this time of sowing.  Plant densities of 60 and 120 plants/m2 did not influence the grain yield or quality of wheat when sown on the 9th and 23rd April.
• Magenta was the highest ranked variety when sown on 23 April, however other long-mid maturing varieties also compared favourably.
• Mace , the most widely grown variety in the state, maximised yield at the 12 May sowing time.  It out yielded all other varieties at this sowing date.
• There was no influence of sowing time and plant density on the screenings which were below 5% for all varieties at all sowing times.

Very little differences were found in the experimental trials with and without inter-row compaction in 2015 due to localised seasonal conditions. However, another site at Southern Cross where inter-row compaction was used with barley resulted in grain yields up to 2.5t/ha. There was also an indication from black plastic over inter-rows at Southern Cross, that water harvesting can potentially double wheat grain yields from 0.8 t/ha to 1.6 t/ha. The latter highlights that the benefits of compacted inter-rows could potentially be maximised using a water-harvesting, spray-on polymer on the compacted inter-row.

• Seeding date had a greater influence on oat grain yield, oat grain quality and return per hectare ($/ha) than variety selection or seed rate in 2015.
• Delaying seeding from early May to early June reduced grain yield by 32% and return per hectare by 45%.
• In lower rainfall environments Bannister is a better option than Carrolup, Williams and Yallara.
• When released, WA02Q302-9 will be a useful oat variety in situations where low hectolitre weight is consistently a problem or with later seeding opportunities.
• Maximum return per hectare was achieved between a target density of 100 to 200 plants/m2, which is in line with the suggested target density for grain oats in low rainfall areas of 160 plants/m2.
• The return per hectare of Bannister oat was maximised at a higher density than for Carrolup, WA02Q302-9, Williams and Yallara, suggesting Bannister should be sown at a higher target density than those varieties. This is a preliminary observation and more research is needed to confirm the optimum target density for the new milling oat varieties.

• Time of sowing had a greater influence on oat grain and hay yield, and oat grain quality than variety selection or level of applied nitrogen in 2015.
• High screenings limited the ability of grain to meet Oat1 quality standards, this was due to the detrimental impact of delayed seeding and/or applied nitrogen in excess of that required in lower rainfall environments.
• Applying more than 20 kg N/ha did not improve the return per hectare ($/ha); rather, applying 80 kg N/ha consistently reduced return per hectare ($/ha).
• Screening of Williams and Carrolup were more sensitive to applied nitrogen than WA02Q302-9, Bannister and Yallara.
• WA02Q302-9 appears a suitable replacement for Yallara and Carrolup, and should achieve a better hectolitre weight than Bannister at similar or lower yields.

• Yields at very low seed rates of 0.3 and 0.5 kg/ha were comparable to yields at higher seed rates of 1.0 and 2.5 kg/ha when using a precision seeding machine.
• Yields in excess of 2.0 t/ha were achieved when sowing at 50 cm row spacing.
• These results suggest we should continue investigating more precise seed delivery systems.

• Yields at very low seed rates of 0.3 and 0.5 kg/ha were comparable to yields at higher seed rates of 1.0 and 2.5 kg/ha when using a precision seeding machine.
• Yields in excess of 2.0 t/ha were achieved when sowing at 50 cm row spacing.
• These results suggest we should continue investigating more precise seed delivery systems.

• Heavy infestation of aphids caused significant yield loss to canola in a high rainfall environment.
• The length of cabbage aphids on spikelets at flowering was directly proportional to yield loss.
• The function yield (kg/ha) = -141x + 1114 where x= spike length colonised in cm explained yield loss R2 0.9.
• Aphid colonisation also reduced seed quality: oil content and seed size.

In this 2015 trial;

• Economic response plateaued at 75 kg N/ha – lower than grain yield (125 kg N/ha)
• Nitrogen applications at 12 and 14 weeks produced similar canola responses to N applied earlier in the year – but no added benefit.
• OP TT and hybrid RR varieties had a similar response to nitrogen timing and rate.

 

• Amira albus lupin is a good break crop option for high and medium rainfall areas of the northern region
• Albus lupin grown in 44 cm rows yielded 81% of 22 cm rows.
• Maintaining a high seed rate maximised yield at both 22 and 44 cm row spacing’s.
• In dry conditions fungal disease were not evident, therefore we could not assess the impact of row spacing and density on foliar diseases.

• Most canola had acceptable losses prior to harvest, even with delayed harvest.
• The greatest proportion of losses occurred at harvest.
• The podguard variety IH51RR had significantly less losses than other varieties both before and at harvest.

(i) Several options exist to ameliorate subsoil acidity with incorporated lime. The method chosen will depend on pH profile, yield potential, budget, area affected, soil type and occurrence of other constraints that may be impacted. (ii) Modified deep ripping techniques can incorporate more topsoil and surface applied lime while at the same time effectively removing subsoil compaction. (iii) Applying adequate lime to ameliorate the soil pH profile to depth is of utmost importance and the rate of lime applied should not be compromised to pay for incorporation, although lime applications can be split with some applied before and some a year or two after incorporation.

• RR hybrid canola maximised gross margins
• OP TT variety Sturt produced similar gross margins to the hybrid TT variety Hyola 450 TT
• Gross margins were optimised at:

             ~ 50 plants/m² for Sturt TT.

                5 to 25 plants/m² for Hyola 450TT.

              ~ 13 plants/m² for Pioneer 43Y23 RR.

 

Canola yields in low and medium rainfall regions of south-western Australia are inherently low and variable.  We have shown that although N fertilisation increases the yield of canola, the yield increases are often relatively low.  Nitrogen also reduces the concentration of oil in the seed of canola and the rate of decrease can be rapid in low rainfall areas. 

The combined effect of N on yield and oil, along with the current payment structure for high oil canola, results in uncertain economic returns from N fertilisation in low to medium rainfall areas. 

We found that 90% of maximum gross margin was achieved at an average nitrogen rate of 17 kg N/ha, and the first 10 kg N/ha gave a return on investment in N greater than $1.50 per $1 in 80% of occurrences (experiments x variety combinations).  The next 20 kg N/ha applied gave a return on investment in N of $1.25 for every $1 spent on N in 80% of occurrences, and further increases were most likely to breakeven. 

We have shown that while farmers should continue to plan to apply N onto canola within the first eight weeks, delaying top-up N until 12 weeks after sowing – when the canola crop is near flowering, is a viable second option which provides some level of risk management for canola growers in low and medium rainfall areas in south-western Australia.

In this 2014 trial at Kojonup-West:

• Canola grain yield and gross margins were more dependent on nitrogen rates than the application timings.
• There was no effect of delayed nitrogen application on grain yield or gross margins up to 100 kg N/ha.
• At 125 kg N/ha, a significant yield and gross margins reduction was observed when nitrogen was applied as a 3-way split (50 kg within 8 weeks, 50 kg/ha at 12 and 25 kg/ha at 16 weeks after seeding) compared to when all of the nitrogen was applied within 8 weeks of seeding.

• Grain yield responded to applied nitrogen up to 30 kg N/ha.
• Highest oil %, oil yield and gross margins were obtained with no applied nitrogen.
• When nitrogen was applied, did not alter the yield, oil or $/ha response to nitrogen of both varieties.
• Thus 30, 50 or 70 kg N/ha applied either in splits at seeding and 8 weeks or seeding and 12 weeks provided similar responses.

•  In a dry year, there was no economic response to applied N.  

• Pioneer 43Y23 (RR) perform better in terms of higher grain yield, oil yield and gross margins than Sturt TT, with both varieties producing similar oil %.
• Grain yield responded to applied nitrogen up to 30 kg N/ha.
• Maximum oil% was produced with no applied nitrogen.
•  Gross margins also responded to nitrogen application up to ~ 30 kg N/ha after which further increases in nitrogen led to no further financial gain.
• Overall when nitrogen was applied it did not alter the response to nitrogen of both varieties for GY, oil, oil yield and GM. 

• With grain yield of less than 400kg/ha, there was no grain yield response to applied N and no economic response to applied N.
• At ‘low rainfall’ N rates of 30 kg/ha top-up N at 12 weeks gave a similar response to top-up N within 8 weeks.

• With grain yield of less than 1 t/ha, there was only a small grain yield response to applied N and no economic response to applied N.
• Top-up N at 12 weeks gave a similar response to top-up N at 8 weeks.

• Pioneer 43Y23 (RR) had higher grain yield, oil yield (kg/ha) and gross margins, than Sturt (TT).
• Grain yield responded to applied nitrogen up to ~ 40 kg N/ha.
• Both varieties responded similarly to applied nitrogen with no variety x N rate interaction for grain yield. 
• Oil yield and gross margins did not respond to applied nitrogen.
• Timing of nitrogen application did not alter the response to nitrogen of both varieties for GY, oil %, oil yield or gross margin.

• Grain yield responded to applied nitrogen up to 70 kg/ha.
• Oil did not decrease as nitrogen rate increased, unlike what we have observed at other trials – probably a reflection of the continued grain yield response to N.
• Positive gross margin returns were seen at 40-70 kg/ha of applied nitrogen.
• Overall when nitrogen was applied did not alter the response to nitrogen – but avoid putting the majority of N at 12 weeks.

• Canola grown in wide rows (50-60cm) yielded well enough to consider this row spacing as an option.
• Canola plants were able to compensate for being sown in wide rows - biomass similar to narrow rows.
• We may be able to reduce input costs, seed and fertiliser by refining the production package in wide rows.
• Wide rows offer benefits of reduced fuel costs at seeding, easy stubble handling and safety of IBS herbicides.

• Canola grown in wide rows (50-60cm) yielded well enough to consider this row spacing as an option.
• Canola plants were able to compensate for being sown in wide rows - biomass similar to narrow rows.
• We may be able to reduce input costs, seed and fertiliser by refining the production package in wide rows.
• Wide rows offer benefits of reduced fuel costs at seeding, easy stubble handling and safety of IBS herbicides.

• Canola grown in wide rows (50-60cm) yielded well enough to consider this row spacing as an option.
• Canola plants were able to compensate for being sown in wide rows - biomass similar to narrow rows.
• We may be able to reduce input costs, seed and fertiliser by refining the production package in wide rows.
• Wide rows offer benefits of reduced fuel costs at seeding, easy stubble handling and safety of IBS herbicides.

 

• Grain yields of most canola varieties at Salmon Gums started to plateau at ~ 20 plants/m²
• Taking into account the costs of increasing plant density we calculated the economic optimum for higher cost seed types such as RR and hybrid TT to be 25 plants/m² or less
• Hyola 404RR had the flattest response indicating its yields were less affected by lower plant densities.

• Birds preferentially attacked low density treatments and late maturing variety Hyola 450TT.
• The results from this site should be treated with caution.

In this 2013 trial:

• Canola yield responded to increasing plant density to 65 plants/m² but there was very little response at densities greater than 20 to 30 plants/m²
• The response was variable within this trial site, which means that is very likely to be quite variable across different years and locations. 
• Roundup Ready canola enabled much better weed control than triazine tolerant canola on this site.

In stressed conditions canola yields and gross margins were reduced at plant densities above 20 plants/m².

Despite being higher yielding and producing higher oil than CB Telfer TT, the higher seed costs of hybrid triazine tolerant variety Hyola 450TT resulted in lower gross margins.

Hybrid RoundupReady cultivar Hyola 404RR produced the highest yields and oil at Mullewa in 2013. 

Despite higher upfront costs Hyola 404RR also produced the highest gross margins.

At Chapman Valley in 2013 canola grain yields began to plateau at approximately 20-30 plants/m².  Economic optimum target densities were found to be @ 16 plants/m² for Hyola 404RR, 24 plants/m² for GT Viper, 33 plants/m² for Hyola 450TT, and 34 plants/m² for ATR Stingray.

Taking into account contingencies such as seeding errors, dry conditions at seeding and changes in seed size or viability we suggest that seed rates of RR and TT hybrids and RR OP at similar sites be around 1.9 to 2.3 kg/ha, whilst the cheaper seed of less competitive TT OP lines be sown at @ 4.0 kg/ha.

• In dry years open-pollinated canola can produce small seed in low rainfall areas. Sowing the small seed at a low seeding rate of 2 kg/ha reduced yield and farmers could benefit by increasing the seeding rate to 4 kg/ha  in the following year or purchasing fresh seed.
• Grading small seed hard was not as reliable as increasing the seeding rate to 4 kg/ha.
• F2 hybrid seed produced lower yields than F1 seed unless seeding rates are increased to 4 kg/ha or mixes are made with F1 seed.
• Hybrid TT was less productive than open pollinated TT canola.

In this 2013 trial;

• Applying nitrogen 12 weeks after sowing had a similar effect as the same total nitrogen rates applied earlier.
• Nitrogen reduced on oil%, and late N reduced it more than early N.
• Applying more than 25 kg N/ha to ATR Stingray increased yield but was of little economic benefit. 
• Grain yield of Hyola 404RR responded to 150 kg/ha of applied nitrogen, but gross margin was highest at 75 kg N/ha.