<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The metabolism of the plant growth regulator maleic hydrazide (MH) has been studied in sterile cell suspension cultures of tobacco, soybean, maize and wheat under standardized conditions. Maleic hydrazide was converted to its <italic>O-b</italic> -D-glucoside in yields between 9.0 % (tobacco) 15.0 % (soybean), 5.1 % (maize) and 2.2 % (wheat) respectively. This glucoside was completely cleaved under simulated conditions (pH 1, 37°C, 24 h) of a ruminant stomach. From these results it is concluded that MH-<italic>O-b</italic>-D-glucoside (MHG) belongs to a small group of acid-labile pesticide conjugates (11). The participation of a glucosyltransferase (GT) (EC 2.4.1-) in this conjugation reaction of MH was demonstrated in vitro for the first time. In addition, up to 18 % of the applied maleic hydrazide became associated with nonextractable residues (NER) in soybean, whereas in tobacco only 0.2 % could be detected in this fraction. The residue from soybean cells was solubilized only to a low degree (about 3 %) under simulated stomach conditions, but up to 20 % by the white rot fungus <italic>Phanerochaetechrysosporium</italic>.</p></abstract>

The metabolism of the plant growth regulator maleic hydrazide (MH) has been studied in sterile cell suspension cultures of tobacco, soybean, maize and wheat under standardized conditions. Maleic hydrazide was converted to its O-b -D-glucoside in yields between 9.0 % (tobacco) 15.0 % (soybean), 5.1 % (maize) and 2.2 % (wheat) respectively. This glucoside was completely cleaved under simulated conditions (pH 1, 37°C, 24 h) of a ruminant stomach. From these results it is concluded that MH-O-b-D-glucoside (MHG) belongs to a small group of acid-labile pesticide conjugates (11). The participation of a glucosyltransferase (GT) (EC 2.4.1-) in this conjugation reaction of MH was demonstrated in vitro for the first time. In addition, up to 18 % of the applied maleic hydrazide became associated with nonextractable residues (NER) in soybean, whereas in tobacco only 0.2 % could be detected in this fraction. The residue from soybean cells was solubilized only to a low degree (about 3 %) under simulated stomach conditions, but up to 20 % by the white rot fungus Phanerochaetechrysosporium.

Metabolic Studies of the Growth Regulator, Maleic Hydrazide

GSF Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Biochemische Pflanzenpathologie, Ingolstädter Landstraße 1, D-85758 Oberschleißheim, Germany

ghb Gebrüder Huber Bodenrecycling GmbH, Tannenwaldstr. 2, D-81375 München, Germany

Contributions to Tobacco & Nicotine Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

{"article-title":"Metabolic Studies of the Growth Regulator, Maleic Hydrazide"}

The metabolism of the plant growth regulator maleic hydrazide (MH) has been studied in sterile cell suspension cultures of tobacco, soybean, maize and wheat...

Metabolic Studies of the Growth Regulator, Maleic Hydrazide

Publié en ligne: 06 janv. 2015

Pages: 67 - 74

Reçu: 13 juin 1997

Accepté: 07 nov. 1997

DOI: https://doi.org/10.2478/cttr-2013-0659

© 1997 Beiträge zur Tabakforschung International

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.