Cytogenetics of a reciprocal translocation integrating distichous pedicel and tendril-less leaf mutations inLathyrus sativusL.

Abstract

Grass pea (Lathyrus sativus L.) is a crop with 2n = 2x = 14 chromosomes. Two variants were isolated from 250 Gy gamma ray treated M2 progenies of variety BioL-203: (i) two pedicels per peduncle (distichous pedicel); and (ii) complete absence of tendril in leaf (tendril-less). Occurrence of quadrivalents at meiosis I and partial pollen sterility (48.50%) indicated that the plants were heterozygous for a reciprocal translocation (RT), and were tentatively designated as RT-7. It transmitted at an average of 44% in the progeny, and along with normal fertile plants (N/N), produced trisomic plants (5.76%) with association of five chromosomes in selfed and intercrossed progenies. Test of independence of this newly found translocation was performed by analyzing the pattern of chromosomal ring formation at meiosis I in the F1 progeny of crosses between RT-7 and six previously detected RT lines. Presence of a ring of six chromosomes in F1 plants indicates that the two translocations have one chromosome in common in...