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Differential Responses to Photoperiods in Monoecious and Dioecious Hydrilla verticillata

Published online by Cambridge University Press:  12 June 2017

Thai K. Van*
Aquatic Plant Manage. Lab., Agric. Res. Serv., U.S. Dep. Agric., Fort Lauderdale, FL 33314


Growth and morphology of two U.S. hydrilla biotypes grown under 10- and 16-h photoperiods in outdoor aquaria were investigated. The dioecious hydrilla biotype elongated extensively under both photoperiods and reached the water surface within 2 to 3 weeks after planting. In contrast, the monoecious biotype grew more densely near the sediment, primarily by producing a high number of horizontal stems, root crowns, and higher shoot densities. Monoecious hydrilla grown from tubers produced new tubers after 4 weeks of exposure to the 10-h photoperiod, and the number of tubers produced was five- to sevenfold higher in the monoecious than in the dioecious biotype. Furthermore, monoecious hydrilla produced tubers under both 10- and 16-h photoperiods, with tuber production much higher under the shorter photoperiod. Dioecious hydrilla grown from tubers under similar conditions produced new tubers after 8 weeks only under the 10-h photoperiod. No tubers were produced by the dioecious biotype throughout a 10-week exposure to the 16-h photoperiod.

Weed Control and Herbicide Technology
Copyright © 1989 by the Weed Science Society of America 

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Literature Cited

1. Blackburn, R. D., Weldon, L. W., Yeo, R. R., and Taylor, R. M. 1969. Identification and distribution of certain similar-appearing submerged aquatic weeds in Florida. Hyacinth Control J. 8:1721.Google Scholar
2. Cook, C.D.K. 1985. Range extensions of aquatic vascular plant species. J. Aquat. Plant Manage. 23:16.Google Scholar
3. Downs, R. J. and Hellmers, H. 1975. Environment and the Experiment Control of Plant Growth. Academic Press, New York.Google Scholar
4. Haller, W. T. and Sutton, D. L. 1975. Community structure and competition between Hydrilla and Vallisneria . Hyacinth Control J. 13:4850.Google Scholar
5. Haller, W. T., Miller, J. L., and Garrard, L. A. 1976. Seasonal production and germination of hydrilla vegetative propagules. J. Aquat. Plant Manage. 14:2629.Google Scholar
6. Harlan, S. M., Davis, G. J., and Pesacreta, G. J. 1985. Hydrilla in three North Carolina lakes. J. Aquat. Plant Manage. 23:6871.Google Scholar
7. Klaine, S. J. and Ward, C. H. 1984. Environmental and chemical control of vegetative dormant bud production in Hydrilla verticillata . Ann. Bot. 53:503514.Google Scholar
8. Spencer, D. F. and Anderson, L.W.J. 1986. Photoperiod responses in monoecious and dioecious Hydrilla verticillata . Weed Sci. 34:551557.CrossRefGoogle Scholar
9. Spencer, D. F., Anderson, L.W.J., Ames, M. D., and Ryan, F. J. 1987. Variation in Hydrilla verticillata (L.f.) Royle propagule weight. J. Aquat. Plant Manage. 25:1114.Google Scholar
10. Steward, K. K., Van, T. K., Carter, C., and Pieterse, A. H. 1984. Hydrilla invades Washington, DC and the Potomac. Am. J. Bot. 71:162163.Google Scholar
11. Steward, K. K. and Van, T. K. 1987. Comparative studies of monoecious and dioecious hydrilla (Hydrilla verticillata). Weed Sci. 35:204210.CrossRefGoogle Scholar
12. Sutton, D. L., Littell, R. C., and Langeland, K. A. 1980. Intraspecific competition of Hydrilla verticillata . Weed Sci. 28:425428.Google Scholar
13. Sutton, D. L. 1986. Culture of hydrilla (Hydrilla verticillata) in sand root media amended with three fertilizers. Weed Sci. 34:3439.Google Scholar
14. Van, T. K., Haller, W. T., and Bowes, G. 1976. Comparison of the photosynthetic characteristics of three submersed aquatic plants. Plant Physiol. 58:761768.CrossRefGoogle ScholarPubMed
15. Van, T. K., Haller, W. T., and Garrard, L. A. 1978. The effect of daylength and temperature on hydrilla growth and tuber production. J. Aquat. Plant Manage. 16:5759.Google Scholar
16. Van, T. K. and Steward, K. K. 1986. The use of controlled-release fluridone fibers for control of hydrilla (Hydrilla verticillata). Weed Sci. 34:7076.Google Scholar
17. Verkleij, J.A.C., Pieterse, A. H., Horneman, G.J.T., and Torenbeck, M. 1983. A comparative study of the morphology and isoenzyme patterns of Hydrilla verticillata (L.f. Royle). Aquat. Bot. 17:4359.Google Scholar