title: Localization of the genes controlling B chromosome transmission rate in maize (Zea mays ssp. mays, Poaceae).
abstract: In previous papers we found that the frequency of B chromosomes in native races of maize varies considerably in different populations. Moreover, we found genotypes that control high and low transmission rates (TR) of B chromosomes in the Pisingallo race. In the present work crosses were made to determine whether the genes controlling B-TR are located on the normal chromosome set (As) or on the B chromosomes (Bs). We made female f.0B × male m.2B crosses between and within high (H) and low (L) B-TR groups. The Bs were transmitted on the male side in all cases. The mean B-TR from the progeny of f.0B (H) × m.2B (H) and f.0B (H) × m.2B (L) crosses was significantly higher than that from f.0B (L) × m.2B (L) and f.0B (L) × m.2B (H) crosses. The results show that the B-TR of the crosses corresponds to the H or L B-TR of the 0B female parents irrespective of the Bs of the male parent. This indicates that B-TR is genetically controlled by the 0B female parent and that these genes are located on the A chromosomes.
authors.affiliation: Instituto Fitotécnico de Santa Catalina (FCAF, UNLP)-Centro de Investigaciones Genéticas (UNLP-CONICET-CIC), C.C. 4, 1836 Llavallol, Buenos Aires, Argentina; and.
authors.forename: A M
authors.initials: AM
authors.lastname: Chiavarino
authors.forename: M
authors.initials: M
authors.lastname: Rosato
authors.forename: P
authors.initials: P
authors.lastname: Rosi
authors.forename: L
authors.initials: L
authors.lastname: Poggio
authors.forename: C A
authors.initials: CA
authors.lastname: Naranjo