Role of IAA - Oxidase in Abscission Control in Cotton ' 2 , 3
نویسندگان
چکیده
Suimnwijitiry. The potential role of indoleactic acid (IAA)-oxidase as an in vivo abscission regullating system in the cotton (Gossvpiutiii hirsttuni L.) cotyledonary explant was investigated. Phenols (utsutally monophenols), which are cofactors of cotton IAA-oxidase in vitro, accelerated abscission. Phenols (tustually orthodihydroxyphenols), which inhibit cotton IAA-oxidase in vitro, inhibited abscission. Inhibition or stimulation of abscission was accomplished by phenols both with and without IAA. Results were similar when treatments were applied as lanolin pastes to the cuit petiole ends or as solutions in which explants were submerged. An abscission accelerating phenol stimtulated the decarboxylation of IAA-1-14C by explants and an abscission inhibiting phenol inhibited the decarboxylation of IAA-1-'4C. The mechanism of abscission regtulation by the phenolic compounds was concluided to involve auxin destrtuction via IAA-oxidase. In addition to the direct relationship of this stuidy to abscission, the restults suipport the more general hVpothesis that IAA-oxidase acts in vivo to regullate atuxin levels.
منابع مشابه
Role of IAA-Oxidase in Abscission Control in Cotton.
The potential role of indoleactic acid (IAA)-oxidase as an in vivo abscission regulating system in the cotton (Gossypium hirsutum L.) cotyledonary explant was investigated. Phenols (usually monophenols), which are cofactors of cotton IAA-oxidase in vitro, accelerated abscission. Phenols (usually orthodihydroxyphenols), which inhibit cotton IAA-oxidase in vitro, inhibited abscission. Inhibition ...
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