Tannin Content and Inheritance in Common Bean¹

Abstract

Estimation of tannin in common bean ( Phaseolus vulgaris L.) seed using a modified vanillin‐HC1 procedure revealed that white‐seeded strains contained no detectable amounts, and that, when present in colored seeds, tannin was located in the testae. Although dark‐colored seeds contained the highest amount, we did not find a strong relationship between tannin content and seed coat color. Analyses of four F 2 populations, resulting from crosses between parents that differed in testa color and tannin content, revealed a high broad‐sense heritability for tannin content. The segregation patterns were similar in three of the four F 2 populations, and a few genes seem to be responsible for genetic differences. In the F 2 populations, seeds with black testae contained the most tannin, but recombinant types having black and other colors and relatively low tannin were identified. Low tannin strains may be obtained either by selecting among existing pure lines or by crossing and selecting for appropriate recombinants.