Inheritance of crippled trifoliolate leaves occurring in interracial crosses of common bean and its relationship with hybrid dwarfism

Abstract

Crippled trifoliolate leaves were observed in two lines from interracial populations of common bean (Phaseolus vulgaris l.). The lines, wa 7807-305 and TY 5578-220, were F2-derived F3 recombinant inbreds from populations Rio Tibagi/ABA 58 and Brasil 2/ICA L 23, respectively Rio Tibagi and Brasil 2 are small seeded, grow in tropical lowlands, and belong to the race Mesoamerica. In contrast, ABA 58 and ICA L 23 belong to the large-seeded Andean race Nueva Granada, the two lines were crossed with each other, with one of their normal parents, and with tester stocks. The normal parents and tester stocks carried either the Dl1 or Dl2 gene. These genes are complementary dominant, dosage dependent lethal, and known to cause hybrid dwarfism or plant stunting the recessive gene lcr causes trifoliolate leaf crippling in the presence of either Dl1 or Dl2 when both Dl1 and Dl2 are present, a dwarf-lethal or semilethal phenotype is produced, irrespective of the alleles at the lcr locus. Thus, the genotypes of the lines are, for WA 7807-305: Dl1 Dl1 dl2 dl2 lcr lcr, and for TY 5578-220: dl1 dl1 Dl2 Dl2 lcr lcr. Other reported cases of developmental abnormalities are reviewed and their significance for common bean improvement is discussed.