Lupins in agriculture
Cultivation of lupins is recorded as early as 2000 BC in Egypt and the crop was well-known by Greek and Roman times1. The first Old World lupin to be used in agriculture was white lupin (L. albus), which was used as a green manure crop for raising soil fertility and for its large seed. Yellow lupin (L. luteus) is thought to have been a long-established minor crop in the Iberian Peninsula, North Africa and Madeira but became more broadly adopted after its introduction to Northern Germany in the 1800’s to raise the fertility status of sandy soils. Andean lupin (L. mutabilis, also known as ‘tarwi’) has been cultivated in the Andes for 3000 years. The bitter alkaloids present in high concentrations in lupin seeds of old varieties and landraces were removed by boiling and prolonged leaching in water. All modern varieties have been bred for ‘sweetness’, meaning they contain much reduced levels of alkaloid in the seeds.
Currently, the most widely grown lupin species is the most recently domesticated species: narrow-leafed lupin (L. angustifolius). Its domestication was initiated in Germany in the early 20th Century and was completed in the 1960s by J.S. Gladstones at The University of Western Australia (Perth, Australia). Narrow-leafed lupin thrives in nutrient-poor sandy soils, assisted by its ability to symbiotically fix atmospheric nitrogen and efficiently mobilise chemically-inert phosphorus in the soil. For decades, narrow-leafed lupin has been the primary legume break crop in cereal rotations in the grain-belt of Western Australia where the cereal yield benefit it confers is evident even after three successive seasons of wheat cultivation2. This yield advantage may arise from a combination of factors including increased nutrient availability, reduced weed pressure and its role as a disease break.
Lupin cultivation has experienced decline in many regions including Australia and Europe for a range of reasons not least the persistently low price for lupin grain to be used as an animal feed. We expect this trend to be reversed as lupin increasingly finds its place as a human food and in aquaculture where it can command a higher grain price.
1. Gladstones JS (1970) Lupins as crop plants. Field Crop Abstracts 23:123-148
2. Seymour M, Kirkegaard JA, Peoples MB, White PF, French RJ (2012) Break-crop benefits to wheat in Western Australia – insights from over three decades of research. Crop and Pasture Science 63:1-16