narrow-leafed lupin
organism / organism-lupinus-angustifolius
青花ルピナス / narrow-leafed lupin (sweet lupin) / Lupinus angustifolius
Narrow-leafed lupin is a legume bred as a grain and forage crop in Europe and Australia. Wild forms contain large amounts of bitter quinolizidine alkaloids, but low-alkaloid (“sweet”) lines were discovered in the first half of the 20th century, providing the basis for varieties that can be eaten directly.
On this page (7 sections)
Reading the bitterness
Narrow-leafed lupin (Lupinus angustifolius) includes bitter varieties with high quinolizidine alkaloid (QA) concentrations and varieties with lower levels. One study compares alkaloid accumulation and expression of a biosynthesis-related gene, lysine decarboxylase (LDC), in developing seeds and pods of bitter (high-QA) varieties. The same source notes that breeders have developed low-alkaloid 「甘い」 (in translation: "sweet") varieties to avoid the need for a debittering step.
A 2017 review proposes one direction for lupin breeding: plants with a combined 「苦味/甘味」 (in translation: "bitter/sweet") phenotype, retaining enough alkaloid in vegetative tissues such as stems and leaves to deter insect damage while keeping seed alkaloids low. The abstract of a 2020 review likewise confirms that its authors propose combined varieties with high alkaloids in vegetative tissues and low alkaloids in seeds while retaining disease resistance.
Both reviews propose breeding directions that use low-bitterness and bitterness-retaining varieties according to purpose. They do not identify varieties actually registered and in circulation; these remain future breeding goals.
A 2025 review groups lupins broadly into 'sweet' and 'bitter' varieties by their quinolizidine alkaloid content. Citing prior work, it states that sweet varieties contain less than 200 mg/kg, whereas bitter varieties have relatively high levels of roughly 15,000–22,000 mg/kg.
Sources for this overview
Quinolizidine alkaloids are transported to seeds of bitter narrow-leafed lupin
Checked for this overview: Used the contrast between bitter and sweet varieties.
Quinolizidine Alkaloid Biosynthesis in Lupins and Prospects for Grain Quality Improvement
Checked for this overview: Used the proposed combined phenotype in the 2017 review.
Checked for this overview: Used the similar proposal in the 2020 abstract. / Used the limitation that these remain at the proposal stage.
Checked for this overview: Approximate alkaloid levels of sweet and bitter varieties.
Other names: sweet lupin (en), Lupinus angustifolius (la)
Structured claims — open a section to read each claim's confidence, evidence and limits
Composition and content (1)
Scope: Layer: literature (a review account citing Náthia-Neves et al. 2025 as its original source, thus a secondhand citation).
Note: Secondhand citation (the original Náthia-Neves et al. 2025 was not read). The review’s full text was checked (full_text_checked).
Show data
organism-lupinus-angustifolius —has_composition→ "The review states that lupins are broadly categorized by their quinolizidine alkaloid content into 'sweet' varieties (less than 200 mg/kg) and 'bitter' varieties (roughly 15,000–22,000 mg/kg)."Culture (1)
Scope: Narrow-leafed lupin breeding programs
Note: 2 independent reviews (Frick 2017 and Vishnyakova 2020) propose the same direction, but in both cases this is a description of a future breeding goal, not an already-realized registered cultivar.
Show data
organism-lupinus-angustifolius —has_variation_maintained_by→ "A proposal, as a future breeding goal, for a combined 'bitter/sweet' phenotype that maintains a high alkaloid concentration in the vegetative parts (leaves and stems) to deter insect damage, while keeping the alkaloid concentration low in the seed."