Pisum Genetics 

Volume 24


Forum - The 'bipartitus' phenotype

page 90

Correction to the description of the expression of the 'bipartitus' (bip) gene in some of the published literature

Green, F.N., Winfield, P.W.


Ambrose, M.J.

Scottish Agricultural Science Agency,

East Craigs, Edinburgh EH12 8NJ, UK

John Innes Institute, Colney Lane, Norwich NR4 7UH, UK

In 1989, a coloured flowered accession of cv. Sabre originating from Suttons Seeds was grown for bulking and characterisation. We observed that the lower part of the wings were paler than normal to almost decoloured. In addition, a small decoloured streak was often present, which was occasionally more triangular in shape, the broadest decoloured area occurring at the wing edge and decreasing towards the standard. This accession was obtained from the Vegetable Gene Bank at Horticultural Research International, Wellesbourne, Warwickshire, UK in 1986, and is duplicated in the collection at the John Innes Institute in Norwich where a similar observation was made in 1991.

The phenotype described above is a 'mirror image' of the phenotype conferred by the 'bipartitus' gene (bip) according to the description by Blixt (1). He described the 'bipartitus' phenotype as having the upper part of the wings paler coloured.

In 1991, the representative line for bip, WL2024, was grown for bulking under glass and positioned beside the cv. Sabre for comparison. The lower part of the wings was found to be paler, almost decoloured in WL2024 - not the upper part as described by Blixt (1). However, Lamprecht (3, 4) illustrates the character in the same way as we observed it, but the drawing of the wing is presented vertically rather than in a horizontal orientation, which may have led to the error in subsequent published descriptions. If this mistake is not corrected, it will continue to be perpetuated as has already happened (2).

The possibility that the representative line differs from the type line by having the paler wing area in a different position is unlikely. The representative line, WL2024 (A bip), is a derivative (F6 generation) of a cross between the type line, WL680 (a bip), and line WL851 (Blixt personal communication).

In summary, the bip gene should therefore be described as causing the lower portion of the wings to be paler than normal to almost decoloured.

  1. Blixt, S. 1972. Agri Hort. Genet. 30:1-293.

  2. Jaiser, H. 1990. Compendium of Pea Genes. Private publication. Berlin.

  3.  Lamprecht, H. 1962. Agri Hort. Genet 20:156-166.

  4.  Lamprecht, H. 1974. Monographie der Gattung Pisum, Steiermärkische Landesdruckerei, Graz.