Canola and lupin, comparing varieties by time of sowing in the northern agricultural region, Eradu 2017 trial report

Background and aim

Initially the purpose of this trial was to test very early (March) sowing however, due to the late break to the season this was not possible. Instead this trial compares lupins and canola which have emerged in late May and late June.

Trial details and treatments

The trial was conducted at Eradu, 50km east of Geraldton. Treatments included 10 varieties (five canola and five narrow leaf lupin) and three times of sowing (TOS) (11 April - dry, 5 May - dry and 25 May).

The varieties included a range of season lengths: Canola - Pioneer 43Y23 RR (early), GT50 (mid), GT 53 (mid), Hyola 600RR (long), Hyola 725RT (very long) and lupin varieties - Mandelup (early), PBA Jurien (early), PBA Barlock (early/mid), Tanjil (mid) and Danja (long).

The trial was designed such that species (canola/lupin) and TOS were blocked to enable trial management. Varieties were randomised within these blocks and there were four replicates of each treatment. Measurements included plant density, ground cover, plant biomass, weed density, flowering dates, seed yield and seed quality.

Results

Rainfall at the site was 188mm from May-October. The first rain for the season was not received until the third week in May hence the first two sowing times emerged at the same time.

Plant density for the lupins averaged 29 plants/m² and canola averaged 25 plants/m². Field establishment for both species was around 30% even for seed which was sown dry and in the ground for 40 days prior to rain.

Dry matter averaged over all treatments was 616g/m²_, when measured on 2 October. Lupins averaged 652g/m² and canola averaged 582g/m², a significant difference (P <0.001). Dry matter production was not significantly different for TOS1 and TOS2, which is not surprising given they emerged at the same time. Dry matter production from TOS3 was significantly lower, (P <0.001) approximately 80% of TOS1 or TOS2. This was caused by a reduction in canola biomass from TOS3. The very low plant density of canola from TOS3 would have contributed to this. Consequently there was a species by time of sowing interaction; lupin biomass significantly greater than canola at TOS3 but not at TOS1 or TOS2 (Figure 1).

Figure 1. Plant biomass (g/m²)  as of October 2

Lupins yielded more than canola (P <0.001) 2789kg/ha compared to 1683kg/ha. Yield from TOS1 and TOS2 were not significantly different for either lupin or canola, as would be expected considering they emerged at the same time. Averaged across all varieties lupins yielded similarly from all sowing times - 2714kg/ha from TOS1, 2686kg/ha from TOS2 and 2968kg/ha from TOS3. The result is unusual within the northern agricultural region where delays in crop establishment after early May almost always result in a yield penalty. It is likely the atypical season in 2017, with good stored soil moisture from rain in January and February a higher than average rainfall in August and mild September and October conditions with 11 rain days in September resulted in similar conditions for growth, podding and seed fill for all times of sowing. There was a significant difference in lupin variety yield (P <0.001) with the newer varieties, PBA Jurien and PBA Barlock yielding more than Tanjil and Mandelup, with the 1986 released variety Danja yielding lower than all other varieties.

Yield averaged across all canola varieties was 2053kg/ha from TOS1, 2009kg/ha from TOS2 and 987kg/ha from TOS3. This was a significant difference across the sowing times (P <0.001). As noted above the TOS3 canola established very poorly and it was mid to late July before plants started to grow well. Hence there was approximately a month difference in establishment from TOS1 to TOS2 and a yield loss of approximately 34kg/ha/day. There was difference in varieties (P <0.001). GT53 was the highest yielding variety and Pioneer 43Y23 RR and Hyola 725RT yielded significantly less than all the other varieties.

Figure 2. Yield of variety when sown on April 11 (TOS1), May 3 (TOS2) and May 25 (TOS3)

Lupin protein was low, averaging 29% and did not change significantly with sowing time. There was little difference between varieties with a range of 28.8-31.1%.

Canola oil concentration averaged over all varieties was 44.9% for TOS1, 45.3% for TOS2 and 40.8% for TOS3. This was a significant reduction (P <0.001) at TOS3. The varieties did differ in oil concentration (P <0.001), longer season varieties had the highest oil with a range from 41.6% (Pioneer 43Y23 RR) to 45.3% (Hyola 600RR).

There was a large range in gross margin from -$74/ha to $837/ha. Canola was the most profitable species from TOS1 and TOS2 however low yields at TOS3 meant it was much less profitable than lupins from this sowing time. Return on investment was highest for lupin due to lower input costs. The later released lupin varieties were more profitable, in particular PBA Jurien performed well from all sowing dates.

Conclusions

The results of this trial are atypical of time of sowing responses observed in the northern agricultural region. They highlight how important spring conditions and stored soil moisture are in determining the productivity of late emerging crops. Both lupin and canola were profitable from the first two sowing dates and it was interesting to note that lupins gave the highest return on investment.

Acknowledgements

Thanks to Stephanie Boyce and the Geraldton RSU for trial management and measurements and Bruce Ley for supplying the site.

PBA Jurien and PBA Barlock are protected under the Plant Breeders Rights Act 1994.

GRDC project number: DAW00227. Trial number 16GE20.