|OCUMPAUGH W R|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/31/1996
Publication Date: N/A
Interpretive Summary: Germplasm registration--no interpretive summary required.
Technical Abstract: As a Panicoid grass seed germinates, the coleoptile is elevated to the soil surface by cell division at the crown node. The cell division and cell elongation produce a structure called the subcoleoptile internode. Elongation of the subcoleoptile internode stops when the coleoptile tip receives an adequate amount of red light. This process operates to insure that the crown node remains slightly below the soil surface. Location of the crown node is significant because adventitious roots required for successful seedling establishment originate from the crown node. Elevation of this structure above the soil surface impedes development of these roots. To determine if crown node placement (relative to the soil surface) could be modified, we performed three cycles of recurrent selection in kleingrass (Panicum coloratum) for high and low crown node placement under dim, continuous light. Selection was successful in both cases. The cycle three high and low crown germplasms have been designated as TEM-EC and TEM-LC, respectively. When grown under low light, crown placement was 1.94 cm above the soil surface for TEM-EC and 0.035 cm for TEM-LC. The base population, 'Selection-75', had a crown node elevation of 0.87 cm under these conditions. These germplasms should be valuable for studying the physiological processes regulating crown node placement.