Abstract

Four domesticated lupin species, white lupin (L. albus L.), narrow-leafed lupin (L. angustifolius L.), yellow lupin (L. luteus L.), and sweet pearl lupin (L. mutabilis Sweet.) are cultivated in about 1 Mha around the world. The life cycle of lupin can be divided into three phases: vegetative, floral and pod, and seed growth. Most lupins are indeterminate, with vegetative growth during reproductive state, but there are cultivars with restriction of branching or ‘determinacy’. Time to flowering is modulated by temperature, vernalisation, and photoperiod. Shoot dry weight, intercepted photosynthetic active radiation, and radiation use efficiency (RUE) exhibited large variability in L. angustifolius and L. albus, depending on environmental conditions. Nitrogen fixation through symbiotic association with Bradyrhizobium lupini can yield around 21kgN per ton of shoot dry weight. Proteoid (cluster) roots develop in L. albus and L. cosentinii but not in L. angustifolius. These cluster roots release large quantities of carboxylic acids (malic and citric) and acid phosphatase increasing the soil P availability. Lupins are sensitive to soil water stress exhibiting a rapid reduction in stomatal conductance and strong decrease in grain yield. In L. angustifolius, the critical period for grain yield determination is between 10 days before anthesis and 50 days after anthesis. The yield potential of lupins is high (6tha-1), and in rotation with cereals, can play a role on agricultural sustainability in Mediterranean and temperate environments.