|Sun, Huan - JILIN ACADEMY, CHINA|
|Zhao, L - JILIN ACADEMY, CHINA|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 9, 2000
Publication Date: N/A
Interpretive Summary: The hereditary information that is passed from generation to generation through sexual reproduction is on structures termed chromosomes. Changes in chromosome structure can occur. One such change results in a reverse orientation of segments of the chromosome and is called an inversion. Three soybean varieties from China were identified with inversions. Two varieties had the identical inversion while the third variety had a different inversion. Since inversions cause partial male and female sterility, knowledge about the distribution of inversions in soybean varieties is important to plant breeders.
Technical Abstract: One type of chromosome aberration, an inversion, results in the reverse orientation of genes on a chromosome. In soybean, three accessions (Plant Introductions) with a paracentric chromosome inversion were identified. Our objective was to determine if the paracentric inversions identified in PI 597.651 and PI 597.652 (Glycine max, cultivated species) and in PI 407.l79 (G. soja, wild annual species) were identical. The G. soja inversion was backcrossed into G. max cultivar Hark. The two G. max accessions from China were intercrossed, and based upon pollen staining of F1 and F2 plants, were considered identical in chromosome structure. The G. soja accession, however, had a chromosome structure different from the two G. max accessions. Meiotic studies confirmed the presence of the paracentric inversions. Crosses of PI 597.651 with either cultivar Hark or Hark homozygous inversion gave F1 plants with two to three times as many meiotic cells with chromosome bridges as cells with laggards and fragments Crosses of PI 567.652 with either cultivar Hark or Hark homozygous inversion, however, gave F1 plants with about equal numbers of meiotic cells with bridges as cells with laggards and fragments. Therefore, cryptic structural differences between these two Chinese accessions might influence chromosome pairing, crossing over, and segregation. This might explain the different meiotic behaviors in crosses of the two Chinese accessions with Hark and Hark homozygous inversion.