ARS | Publication request: EVIDENCE FOR MATERNAL INHERITANCE OF THE CHLOROPLAST GENOME IN CULTIVATED CARROT (DAUCUS CAROTA L. SSP. SATIVUS)

Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 12, 1999
Publication Date: N/A

Interpretive Summary: All plants have the ability to produce green tissues. The green color is due to subcellular organelles, called chloroplasts, which in turn contain DNA. Unlike the DNA in chromosomes, which come from both maternal and paternal parents, DNA in chloroplasts sometimes comes from only one parent - sometimes maternal and sometimes paternal. Using a mutation we found in carrot chloroplast DNA, we devised an experiment to determine whether carrot chloroplast DNA comes from the maternal parent, paternal parent, or both. We found that carrot chloroplast DNA always originates from the maternal parent only. This finding clarifies our understanding of carrot chloroplast inheritance and may have some application in testing seed purity by seed companies.

Technical Abstract: The incidence and inheritance of a chloroplast DNA (cpDNA) mutation/marker, BP10U, was studied in crosses among cultivated carrots (D.carota ssp. sativus). BP10U is about 400 bp larger than the more common BP10L allele. The occurrence of BP10U among carrot inbreds was widespread. Individual plants exhibited only one form of BP10 and cpDNA inheritance was strictly maternal. BP10U only occurred in male fertile plants. Some male fertile inbreds and all cytoplasmically male sterile (petaloid) carrots had the BP10L allele. Alloplasmic cpDNA variation has been reported previously in Daucus, but this is the first report of variation and inheritance of cpDNA within cultivated