Abstract
Effects of environmental conditions and growth regulators on release from dormoncy of axillary turions inHydrilla verticillata were investigated.
Coll treatment at 2 C for 33 days produced the most complete release from dormancy. One week of 2 C treatment was sufficient for the germination; however, longer cold periods produced more rapid growth in shoot or root lengths as well as a shorter lag time for germination.
Dormancy in turions could be broken by a photoperiod of 16 hr but not by on of 8 or 12 hr, nor by continuous lighting. When a cold treatment was applied turions grew out in response to all of the photoperiodic conditions.
Red and far-red irradiation during the incubation after a cold treatment promoted gremination; blue and green light markedly inhibited the germination.
At 10−4 and 10−5 M, gibberellic acid broke dormancy of non-cold treated turions, but was toxic at 10−4 M to the development after germination. Gibberellic acid promoted growth of cold treated turions even at 10−6 M. Indoleacetic acid at 10−4, 10−5 and 10−6 M induced outgrowth of both non-cold treated and cold treated turions. Apparently normal growth and development was observed in a high concentration of indoleacetic acid.
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Sastroutomo, S.S. Dormancy and germination in axillary turions ofHydrilla verticillata . Bot Mag Tokyo 93, 265–273 (1980). https://doi.org/10.1007/BF02488733
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DOI: https://doi.org/10.1007/BF02488733