You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
We studied the early root growth of four Setaria taxa: giant foxtail (Setaria faberi Herrm.), giant green foxtail [Setaria viridis var. major (Gaud.) Posp.], robust white foxtail (Setaria viridis var. robusta-alba Schreiber), robust purple foxtail (Setaria viridis var. robusta-purpurea Schreiber). Growth studies in controlled environments showed significant differences in root elongation among the taxa at three photoperiods. Seminal root lengths after 4 days followed the order presented for selectivity and metabolism of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] and propazine [2-chloro-4,6-bis(isopropylamino)-s-triazine] (robust white foxtail > giant green foxtail = robust purple foxtail > giant foxtail). Giant foxtail had the greatest root diameter, resulting in the greatest surface area and volume when lengths were equated. The order of seminal root lengths or diameters changed little after 7 days. Robust white foxtail had the most and longest first order lateral roots. Diameter of first order laterals showed giant foxtail > giant green foxtail = robust purple foxtail > robust white foxtail.
Weed Science © 1975 Weed Science Society of America