Characteristics and implications of prolonged fusicoccin-induced growth of Avena coleoptile sections.
A study has been made of the prolonged growth of Avena coleoptile sections in response to fusicoccin (FC), a phytotoxin that promotes apoplastic acidification. The final amount of FC-induced growth is a function of the FC concentration. Removal of the epidermis speeds up the initial rate of elongation and shortens the duration of the response, without affecting the total amount of extension. A suboptimal FC concentration (7 x 10(-8) M) which induces the same rate of proton excretion as does optimal indoleacetic acid (IAA) (1 x 10(-5) M), causes elongation which is 60-75% of that induced by IAA in 4 h or 50-65% in 7 h. This suggests that acid-induced extension could make a major contribution to auxin-induced growth for at least 7 h.
Cleland
R E
RE
Botany Dept, Univ. of Washington, Seattle 98195, USA.
D018554:Avena / Q000187:drug effects / Q000254:growth & development*; D018548:Cotyledon / Q000187:drug effects* / Q000254:growth & development; D003470:Culture Media / Q000494:pharmacology; D006027:Glycosides / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D007210:Indoleacetic Acids / Q000494:pharmacology*; D019441:Plant Epidermis / Q000254:growth & development; D010937:Plant Growth Regulators / Q000494:pharmacology*; D011189:Potassium Chloride / Q000494:pharmacology; D011522:Protons; D013395:Sucrose / Q000494:pharmacology; D013997:Time Factors
D003470:Culture Media; D006027:Glycosides; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D011522:Protons; C007808:fusicoccin; D013395:Sucrose; D011189:Potassium Chloride; C030737:indoleacetic acid