ISSN:
1432-2048
Keywords:
Growth (root, excision)
;
Pressure probe
;
Root growth (excision effects)
;
Triticum (root growth)
;
Turgor pressure
;
Wall extensibility
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Excision and subsequent incubation of the apices (1 cm) of wheat (Triticum aestivum L.) seedling roots in simple media severely reduced elongation from 28 mm·(24 h)-1 in intact roots to a maximum of 2 mm·(24 h)-1 in excised roots. The reduction in growth was accompanied by a loss of cell turgor in the growing zone but was correlated with a hardening of the cell walls in this region. Rheological properties were measured as percent extensibility (both plastic and elastic) using a tensiometer, and as instantaneous volumetric elastic modulus (ε i) using the pressure probe. Excision decreased plastic and elastic properties with a half-time of some 60 min. Plastic extension was reduced from 2.5% to 0.9% and elastic from 4.8% to 2.6% for an 8-g load. By contrast, ε i was increased by excision. The observed reduction in root elongation rate was accompained by a reduction in mature cell length from 240 μm to 40 μm and a shortening of the zone of cell expansion.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00395421
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