Optimizing lupin production for human consumption in The Netherlands

In a period of 7 years 2007-2013) 25 varieties of lupins were tested on different soil types in The Netherlands, including 20 varieties of L. angustifolius, three varieties of L. albus and two varieties of L. luteus. These varieties were obtained from various seed companies in Germany, Denmark, Poland and the UK,. It seems that relatively small differences in climatic conditions between The Netherlands (northern-european sea climate) and the regions where most of the varieties are bred (north-eastern land climate in Germany or middle European sea climate in the north of France) already result in varieties being less adapted to the growing conditions existing in The Netherlands. An important result is that, although breeding efforts have been focusing on developing low-alkaloid varieties for both feed and food, only a limited number of varieties meet the strict norm of less than 0,02% of alkaloid needed for food. Apart from variety effects, several different crop management factors have clear effect on both yield and grain-quality (alkaloids). Yields appeared to be higher on clayey soils than on sandy soils, although for L. angustifolius free calcium levels need to be sufficiently low to avoid having a lack of inoculation and chlorotic reactions. No yield effect was found with the application of K or S, but alkaloid levels tended to be lowered by the application of KSO₄ in soils low in potassium. Early sowing seems to increase the yield potential of both L. angustifolius and L. albus although early sowing can also cause reduced emergence and increased weed pressures. The application of fungicides did increase the yield of most lupin varieties considerably even in years that fungal-pressure appeared to be low.