Alkaloid content variations in Lupinus luteus L. and Lupinus angustifolius L.

Testing of lupine varieties for alkaloids was performed in the period 2006-2010 at the Voke Branch of the Lithuanian Institute of Agriculture in the course of a competitive trial of feeding lupine (Lupinus sp.). Samples of feeding yellow lupine (Lupinus luteus L.) varieties as well as narrow-leaved lupine (Lupinus angustifolius L.) were used. The alkaloid concentration was assessed in the periods of inflorescence emergence (BBCH 51-55), flowering (BBCH 64-67), development of fruit (BBCH 71-75) and ripening of seed (BBCH 85-88). Exsiccates of leaves, stems, flowers, pods and seeds were used as test material. The results revealed similar average levels of alkaloids in yellow forage lupine (Lupinus luteus L.). Analysis of the average alkaloid levels showed that in all phenological stages in the stems of yellow lupine (Lupinus luteus L.) alkaloid levels were lower than in the narrow-leaved (Lupinus angustifolius L.). At the stage of flowering (BBCH 64-67), the average alkaloid level in the leaves was lower than in the stems. In the course of our investigation, the highest average alkaloid levels were determined in the pods (0.114 ± 0.007) and flowers (0.114 ± 0.006) of narrow-leaved lupines, and the lowest level in the seeds (0.022 ± 0.003) of yellow lupines.