Additional Locus with a Recessive Allele for Red Testa Color in Peanut

Abstract

Seed with red testa color in peanut (Arachis hypogaea L.) are sold as oil stock at reduced price when mixed with tan or pink seed. Although two loci (R1 with a dominant allele for red testa and r2 with a recessive allele for red testa) have been identified, they do not explain all observations for inheritance of red testa. This study was conducted to better define the inheritance of red testa color in peanut and present evidence for a third locus controlling red testa inheritance. Three cross combinations involving five parents having pink or tan testa color were examined. The cross combinations were GA‐T2465 ✕ Tifton‐8, Tifton‐8 ✕ ‘Early Brunch’, and ‘Southern Runner’ ✕ ‘Sunbelt Runner.’ The F2 populations were field grown and examined for testa color. Data for each population fit a 15 tan or pink to 1 red testa segregation ratio. Examination of F3 lines also indicated that segregation for red testa color in these crosses was controlled by complementary recessive alleles at two loci. Because only one locus with a recessive red testa color allele has previously been identified, these results indicated the existence of at least one additional locus with a recessive allele for red testa color. It is proposed that the genotypes for the nonred parents GA‐T2465 and Tifton‐8 be designated r2r2R3R3, and R2R2r3r3, respectively.