How 
          Much of a Stress-tolerant Ruderal is the Arctic-Annual, Koenigia 
          islandica L.

, Qasair Rashid; , Alistair David Headley

Research Article

**How Much of a Stress-tolerant Ruderal is the Arctic-Annual, Koenigia islandica L.**

Qasair Rashid and Alistair David Headley

ABSTRACT

The comparative effects of different stresses on growth and flowering of a stress-tolerant plants, Koenigia islandica L., were examined in controlled growth experiments alongside a typical ruderal, Stellaria media (L) ViLL., and a typical stress-tolerant plant, Minuartia verna (L.) Hiern. Koenigia islandica is fully tolerant of low nutrient supply and low temperature as Minuartia verna. There was relatively little effect of low nutrient supply on concentration of total nitrogen and phosphorus in Koenigia and Minuartia plants, while the size and concentrations of nitrogen and phosphorus in Stellaria was markedly reduced. Koenigia can grow adequately and flower under 8 cm of standing water which neither Minuartia or Stellaria could tolerate. Unlike Minuartia and Stellaria, Koenigia is relatively intolerant to drought. The growth of all three species was reduced by moderate to heavy shading. Koenigia was able to flower and set seed as quickly or slightly before Stellaria when grown at the same temperature or level of nutrient. Koenigia can complete its life cycle in the same length of time as Stellaria, i. e. less than 50 days, and is considered fully ruderal. Koenigia contradicts one of the main assumptions of the CSR life-strategy theory and a more flexible approach to the ordination of plants along three-main axis of competition, disturbance and stress is suggested.

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How to cite this article

Qasair Rashid and Alistair David Headley, 2001. How Much of a Stress-tolerant Ruderal is the Arctic-Annual, Koenigia islandica L. Journal of Biological Sciences, 1: 755-760.

DOI: 10.3923/jbs.2001.755.760

URL: https://scialert.net/abstract/?doi=jbs.2001.755.760

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