Reference Report for IND22017229
Title: | Eight new mutants at the k2 Mdh1-n y20 chromosomal region in soybean |
Authors: | Chen, X.F., Imsande, J., Palmer, R.G. |
Source: | J. Hered. 1999, 90(3):399-403 |
Abstract: | Eight new mutants were isolated at the k2 Mdh1-n y20 chromosomal region in soybean [Glycine max (L.) Merr.]. Among them, genetic type T234 is yellow foliage and malate dehydrogenase 1 (Mdh1) null; cultivar Mandell is green foliage and Mdh1 null. T234 and Mandell were isolated by screening soybean germplasm for malate dehydrogenase variants. CD-9 is a yellow foliage and Mdh1 null mutant identified in a gene-tagging study with the w4-m mutable line. X-193, X-194, PR-95-649, and PR-95-650 are yellow foliage mutants with Mdh1 null and tan saddle seed coat phenotypes identified in the F2 generation from the cross of T239 (k2) with PI567.630A (Mdh1-n) designed to estimate recombination values between the k2 and Mdh1-n loci. A95-K55 is a yellow foliage and Mdh1 null mutant with tan saddle seed coat phenotype identified in the F2 generation from the cross of T239 (k2) with T319 (cyt-Y7). Allelism and inheritance studies were conducted with these eight mutant. The results indicated that the seven new yellow foliage mutants were conditioned by a single recessive nuclear locus and were allelic at the y20 locus. In addition, all eight Mdh1 null mutants were allelic at the Mdh1-n locus. The occurrence of the X-193, X-194, PR-95-649, PR-95-650, and A95-K55 mutants were hypothesized to be due to mutations at the Mdh1 Y20 loci in T239, which resulted in k2 Mdh1-n y20 gametes being produced. Finally, gene symbols were proposed for these eight new mutants and the original gene symbol y15 for T234 has been deleted. |