The Relationships Among Umbelliferone, Growth, and Peroxidase Levels in Cucumber Roots

Abstract

Umbelliferone decreases the elongation rate and initiates a swelling response in cucumber roots. Associated with these growth effects are increases in peroxidase activity in water soluble, salt soluble, and wall bound fractions. The effect on elongation is reversible and is separated in time from the swelling response. Increased peroxidase levels appear after the elongation rate has been reduced but coincident with the swelling response. It is suggested that umbelliferone effects axial elongation and radial expansion through different mechanisms.

Supra-Physiological Levels of Gibberellins / Dellas Modify Root Cell Size / Number and Root Architecture in Root Tips of Arabidopsis Thaliana Seedlings. Connections to the Root Hair Patterning and Abundance

“…Shortening and radial expansion of root cortical and endodermal cells has also been reported in the cobra, pom-1 (both cellulose deficient), shoebox (GA biosynthesis-impaired), dgl1 (GA-insensitive), TUA6/AS (α-tubulin-deficient), erh, sabre, PLD (phospholipase D), wer, scm and jkd mutants, in plants treated with umbelliferone (a cellulose biosynthesis inhibitor), MT-breaking drugs or 1-butanol (an inhibitor of PLD), and in plants stressed by salinity, gamma irradiation or mineral deficiency (Fe, P) [JANKAY & MULLER, 1976;SCHIEFELBEIN & al. 1997;SCHNEIDER & al.…”

“…Therefore, a connection exists between aberrant orientation of MT and reduced cell elongation, as MT regulate the oriented deposition of cellulose microfibrils that determines the direction of cell elongation [BURK & YE, 2002]. More specifically, MT are essential for anisotropic cell expansion because they direct the insertion of cellulose synthase in the CW and guide the orientation of cellulose microfibrils to a perpendicular position with respect to the growth axis, thereby restricting radial cell expansion [JANKAY & MULLER, 1976;LIN & al. 2013].…”

Scanning Electron Microscopy for Studying Root Morphology and Anatomy in Alfalfa Autotoxicity

“…The effect may depend on the type of tissues within the plant and the type of crop. Umbelliferone decreased the elongation of cucumber ( Cucummis sativus L.) root cells but increased their radial expansion (Jankay and Muller, 1976). Several phenolic acids have been found to promote indole acetic acid (IAA) destruction while several others suppress IAA destruction (Lee et al, 1982).…”