Genetic and cytogenetic maps of chromosomes 1R, 4R, and 7R in cultivated rye (Secale cereale)

Abstract
To obtain genetic and cytogenetic maps in rye, two different interchanges, both between 4R and 5R chromosomes, have been studied. In each case, several separate testcrosses for structural and isozyme heterozygous plants and their progeny were analyzed. Linkage was found between the isozyme loci Pgi-1 and Mdh-4 (35.38 centimorgans (cM)), Mdh-4 and Mdh-1 (5.21 cM), Pgi-1 and Mdh-1 (32.37 cM), Mdh-4 and Pgd-2 (28.00 cM), L1Per-1 and Alph-1 (21.43 cM), Alph-2 and Alph-5 (34.37 cM), Alph-2 and Acph (12.24 cM), and Alk-3 and Acph (19.12 cM). Regarding the chromosomes involved in the two translocations, the results obtained in this work are in agreement with previous C-banding data. Thus, the Pgm-1 locus, located in the 4RS chromosome arm, is linked to both translocations. The estimated distance between this locus and the centromere is 14.63 cM in the 4RL/5RS interchange and 16.82 cM in the 4RL/5RL interchange.Key words: translocations, isozymes, rye, genetic and cytogenetic maps.