The Occurrence of Funnel Leaflets and Ring Fasciations in Yellow Lupins

Funnel leaflets in yellow lupins (Lupinus luteus L.) were observedon a mutant, on pea-mosaic infected plants, and on plants treatedwith 2,4-D. In addition typical ring fasciations were producedon plants treated with 2,4-D. The above phenomena have beendiscussed in the light of similar morphogenetic effects, reportedto be induced in other plants by various growth substances.A possible explanation for the ring-shaped structures has beengiven by assuming a change in the influence of the apical meristemon developing leaf primordia and by considering the ‘physiologicalfield’ concept for organ formation respectively.