Bassett (2005) reviewed the literature relating to a gene [cu Prpi] for intensified anthocyanin expression (IAE) in a syndrome of plant organs (flower, pod, stem, and leaf) in common bean. The important commercial effect of [cu Prpi] is the change of pod color from green (with [C prp]) to dark purple pods. The gene [cu Prpi] was the first IAE gene to be reported and was investigated by many bean geneticists over several decades. A second gene for IAE (Prpi-2) was reported by Bassett (2005). The source of Prpi-2 was the Centro Internacional de Agricultura Tropical (CIAT) accession line G07262, which was reported to have genotype t pmic Prpi-2 (Bassett, 2005). The gene t controls the expression of partly colored seedcoat patterns and pmic expresses a short, white micropyle stripe (Bassett, 2003, 2007). The genotype t pmic expressed a long, white micropyle stripe (Fig. 1) in the seedcoat (Bassett, 2005). In the genotype Prpi-2 v, the v gene blocks the expression of IAE. Similarly, with t Prpi-2, the t gene was reported to block IAE in all plant organs except flowers, which were white with blue veins in the wing petals (Bassett, 2005). This tentative hypothesis for blue wing veins expression was based on preliminary data and requires further research for confirmation.
This article reports the inheritance of flower color and pattern controlled by Prpi-2 interacting with tbp, a new gene at the T locus for flower color and partly colored seedcoat patterns, where bp represents blue pattern flower (Fig. 2).
Bassett, M.J. 1994 The griseoalbus (gray-white) seedcoat color is controlled by an allele (pgri) at the P locus in common bean HortScience 29 1178 1179
Bassett, M.J. 2003 Allelism between the P and Stp genes for seedcoat color and pattern in common bean J. Amer. Soc. Hort. Sci. 128 548 551
Bassett, M.J. 2005 A new gene (Prpi-2) for intensified anthocyanin expression (IAE) syndrome in common bean and a reconciliation of gene symbols used by early investigators of gene symbols for purple pod and IAE syndrome J. Amer. Soc. Hort. Sci. 130 550 554
Pedrosa, A., Vallejos, C.E., Bachmair, A. & Schweizer, D. 2003 Integration of common bean (Phaseolus vulgaris L.) linkage and chromosome maps Theor. Appl. Genet. 106 205 212