The success of the Australian albus lupin (Lupinus albus) industry depends on the ability to supply 100% sweet seed.
Sweet seed has low alkaloid content.
Sweetness is controlled by a single recessive gene.
The bitter form of the gene causes seeds to have high alkaloid content – about 1000 times greater than the alkaloid content of sweet seed.
If bitter-contaminated seed lots are sown then contamination will increase with each generation.