Abstract

Media summary

Key words

Narrow leaf lupin, pulses, diversification

Introduction

Two millenia ago, the poet Virgil (70-19 BC) recorded the benefits of growing lupins in a cropping rotation with wheat, “or changing the season, you will sow there yellow wheat, whence before you have taken up the joyful pulse…the bitter lupin’s brittle stalks and rustling grove” Gladstone et al., 1998),. In subsequent centuries, the bitter lupin (caused by a number of alkaloids present in the seed) has been domesticated into a successful crop plant.

There are three lupin species that are grown as a high protein grain crop: white lupin (Lupinus albus), blue lupin or narrow leaved lupin (Lupinus angustifolius) and yellow lupin (Lupinus luteus). This paper will focus on narrow leaved lupin (Lupinus angustifolius) as this is the species that is being investigated for production in Alberta.

Three major genetic improvements have led to the domestication of lupins: 1) a softer seed to ensure even germination, 2) non-shattering pods which ensured that plants could retain their pods to facilitate harvesting, and 3) low-alkaloid (“sweet”) seed content which made the produce edible for both humans and animals. Commercially available lupins that are used for human and livestock use are ‘sweet’ types which contain low levels of alkaloids (Waldroup and Smith, 1989; Nelson and Delane, 1990). Sweet lupin varieties contain 0.01-0.03% alkaloids compared to the ‘bitter’ lupins that contain 0.8-0.9% alkaloids (Gill and Vear, 1980). There are ‘sweet’ white lupins, ‘sweet’ narrow leaved lupins and ‘sweet’ yellow lupins. Only the ‘sweet’ types are grown commercially for human and livestock feed.

Australia is the world’s most well-known success story in regard to lupin production. Australia produces over one million tonnes per year, with a majority of the production occuring in Western Australia. The development of an international market that pays a premium for the high protein and energy crop has led to 75% of Australia’s lupins being exported into international markets. A substantial domestic market has also developed within Australia.

Preliminary work in Alberta has indicated that new European genotypes of Lupinus angustifolius L. (narrow-leaf lupin) are adapted to the prairies. Blade (2003) noted that production of a pulse crop with 35-40% protein and 6-8% crude fat could have beneficial implications for livestock feed (aquaculture, dairy, poultry and swine). The fatty acid profile of lupin seed has been noted as having excellent emollient properties for the cosmetic industry. The low amount of oil (8-10%) means that the seed does not have to be de-oiled, which is the case for some soy-based processes. The excellent tolerance for acidic soils also provides an area for pulse expansion in parts of Canada that currently do not have pulse crop options due to low soil pH. The ability of the crop to fix large amounts of nitrogen has also made lupin of interest to organic/sustainable agriculture producers in both Europe and North America.

Methods

Genotype assessment and agronomy trials

Multilocation trials were seeded to assess genotype adaptation in Alberta. Trials were randomized complete block experiments with four replications. Trials were grown in Edmonton, Brooks and Fairview. Data will be reported only for Edmonton and Fairview. Date of seeding and planting density trials were planted at Edmonton and Fairview. Narrow leaf lupin (cv. Arabella) was used for the seeding density study, and Arabella and G6 were used for the date of planting trial. Plots were seeded with a Fabro drill, hand-weeded and harvested with a Wintersteiger combine. Seed quality assessment was done in cooperation with NorWest Laboratories (Edmonton, Alberta). All data were analyzed using PROC GLM (SAS Institute).

Results

Genotype assessment

At the Edmonton location grain yields ranged from 1809-2510 kg ha^-1, in comparison to the field pea check (cv. Cutlass) yield of 4948 kg ha^-1. The trials at both Fairview and Brooks were not harvested due to severe drought. ^Although the lupins were inoculated, they showed nitrogen deficiency symptoms through the pod-filling phase. It is thought that the inoculant used at Edmonton was not effective.

Agronomy trials

Narrow leaf lupin (cv. Arabella) was planted at three densities (50, 100 and 150 pl/ m²) at Edmonton and Fairview. The Edmonton site grain yield was significantly greater at the highest density (Table 1). Protein content was measured only for the Edmonton site and varied between 36.2-37.2% (Table 2).

Table 1. Grain yield (kg/ha) for three planting densities at Edmonton and Fairview (2003).

Table 2. Protein content (%) for three planting densities at Edmonton and Fairview (2003).

The planting date trial showed excellent grain yields of up to 4.5 tons ha-1 Table 3). The early-maturity exhibited by the tested lines allowed the latest planting, which escaped cold weather in early May, to yield the most grain. Grain protein content ranged from 37.7-38.7% for Arabella and 34.9-37.9% for line G6.

Table 3. Grain yield (kg/ha) for seeding dates at Edmonton (2003).

Table 4. Grain protein content (%) for seeding dates at Edmonton (2003).

Seed composition

Analysis of grain samples resulted in protein range from 31.7-40.8%. Crude fat concentrations varied from 5.1-7.3%. Fatty acid composition of seed oil indicated high proportions of both oleic and linoleic acid.

Table 5. Seed oil fatty acid composition.

Conclusions

• Tested narrow leaf lupin genotypes showed adaptation to western Canadian conditions.
• Yields of 4+ t/ha indicate economic potential for Alberta producers.
• Seed composition results suggest that there is an opportunity for targeting lupin production for specific markets such as aquaculture feed.

References

Blade, S.F. 2003. Adaptation of high protein lupins for western Canada. Canadian Journal of Plant Science (in press).

Gill, N.T. and K.C. Vear. 1980. Agricultural Botany. 3^rd Ed. London: Gerald Duckworth and Co. Ltd.

Gladstone, J.S., Atkins, C.A. and J. Hamblin (Eds). 1998. Lupins as Crop Plants: Biology, Production and Utilization. CAB International.

Nelson, P. and R. Delane. 1990. Producing lupins in Western Australia. In: Lawson, E. (Editor). Bulletin of Department of Agriculture, Western Australia, 4179.

Waldroup, P.W. and K.J. Smith. 1989. Animal feed uses of legumes. In: Matthews, R.H. (Editor), Legumes Chemistry, Technology and Human Nutrition. Marcel Dekker, Inc.