Clarification on the use of symbols apu and pet.

In 1960, a mutant (WL5478) with the phenotype petiolulatus was included in the pea catalogue of the Weibullsholm Plant Breeding Institute by Stig Blixt. The mutant was not analysed genetically. In 1979, Harvey (1) reported a pea mutant (JI1349) with the phenotype apulvinic. In 1984, Marx (2) showed monogenic recessive inheritance of the apulvinic mutant and provisionally assigned the symbol apu. Swiecicki (3) subsequently found mutants petiolulatus and apulvinic to be allelic but was incorrect in assuming that a symbol pet derived from the original phenotypic description should serve as the symbol and be given priority. At no time has the symbol pet appeared in the official Pisum gene list The symbol pet has appeared on the recent editions of the genetic map but in the accompanying listing the symbol apu is cited by Weeden et al. (4).

Precedence in the future will be given to apu as the valid symbol for the locus and pet will subsequently be classified as a synonym. It has been agreed that the mutant phenotype will be standardised to apulvinic. The phenotype description is therefore of leaves where the foliar pulvini are replaced by petiolules.

1. Harvey, D.M. 1979. Seventieth Annual Report John Innes Institute p.34.

2. Marx, G.A. 1984. Pisum Newsletter 16:46-48.

3.   Swiecicki, W.K. 1990. Pisum Genetics 22:66.

4. Weeden, N.F., Ambrose, M.J. and Swiecicki, W.K. 1993. In Genetic Maps 6th edition,
   Ed. S.J. O'Brian, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. pp.
   6.24-6.34.

M.J. Ambrose

Chairman

Pisum Gene Symbols Committee