Auxanometer

An auxanometer (Gr. auxain, "to grow" + metron, "measure") is an apparatus for measuring increase or rate of growth in plants.[1]

In case of an arc-auxanometer (see picture), there is a wire fixed with the plant apex on one end and a dead-weight on the other. It passes over a pulley which has a pointer attached to it. When the plant's height increases, the pulley rotates and the pointer moves on a circular scale to directly give the magnitude of growth.[2]

Sensitive auxanometers allow measurement of growth as small as a micrometer,[3] which allows measurement of growth in response to short-term changes in atmospheric composition.[4] Auxanometers are used in the laboratory,[4] the field,[5] and the classroom.[6]

References

  1. ^  Chisholm, Hugh, ed (1911). "[[Wikisource:1911 Encyclopædia Britannica/{{subst:PAGENAME}}|{{subst:PAGENAME}}]]". Encyclopædia Britannica (11th ed.). Cambridge University Press. 
  2. ^  "Auxanometer". The New Student's Reference Work. Chicago: F. E. Compton and Co. 1914. 
  3. ^ Bovie, W. T. (1912), "A Precision Auxanometer", Botanical Gazette 53 (6): 504, doi:10.1086/330848 
  4. ^ a b Ranson, S. L.; Harrison, A. (1955), "Experiments on Growth in Length of Plant Organs", Journal of Experimental Botany 6: 75, doi:10.1093/jxb/6.1.75 
  5. ^ Gallagher, J. N.; Biscoe, P. V.; Saffell, R. A. (1976), "A Sensitive Auxanometer for Field Use", Journal of Experimental Botany 27 (4): 704, doi:10.1093/jxb/27.4.704 
  6. ^ W. T. Bovie; W. T. Bovie (1915), "A Simplified Precision Auxanometer", American Journal of Botany 2 (2): 95–99, doi:10.2307/2435215, JSTOR 2435215