Nutrient effects on autofragmentation of Myriophyllum spicatum
Smith, D.H.; Madsen, J.D.; Dickson, K.L.; Beitinger, T.L. (2002). Nutrient effects on autofragmentation of Myriophyllum spicatum. Aquat. Bot. 74(1): 1-17
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770; e-ISSN 1879-1522, more
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Keywords |
Chemical elements > Nonmetals > Atmospheric gases > Nitrogen Flora > Aquatic organisms > Aquatic plants Reproduction > Vegetative reproduction Myriophyllum spicatum L. [WoRMS]
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Authors | | Top |
- Smith, D.H.
- Madsen, J.D.
- Dickson, K.L.
- Beitinger, T.L.
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Abstract |
The effects sediment nitrogen and water potassium concentrations have on autofragment production of Eurasian watermilfoil (Myriophyllum spicatum L.) were studied utilizing 16 mesocosms with four mesocosms per treatment. Results indicated that a sediment nitrogen concentration of 0.04mg NH3-Ng-1 sediment significantly increased autofragment production. Plants grown for 12 weeks in this low nitrogen regime produced 1616 autofragments while high nitrogen treated plants (0.55mg NH3- Ng-1 sediment) produced 712 autofragments. Potassium concentration did not significantly alter autofragment production. Up to 50% of autofragments abscised from parent plants grown under low nitrogen conditions compared to 12% or less when grown under high nitrogen conditions. Within 10 days of initiating adventitious roots, 16-38% of autofragments broke away from parent plants grown under low nitrogen regimes compared to 10% of autofragments grown under high nitrogen regimes. Plant components (inflorescence, autofragment, stem and root crown) contained equivalent percentages of total nonstructural carbohydrates (TNCs) by the 9th week of growth; however, low nitrogen treated plants were producing more autofragment and stem biomass. The combination of these factors indicates that Eurasian watermilfoil grown in a low nitrogen environment directs more resources toward autofragment and stem production, allowing colonization of new potential sites. In contrast, when grown in a high nitrogen environment, this species directs more of its energy toward stem and root crown development, allowing for regrowth and colonization in the immediate area. |
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