Relations entre hypolignification et état vitreux chez <i>Salix babylonica</i> en culture <i>in vitro</i>. Rôle de la nutrition ammoniacale

Abstract

The relationship between nitrogen-fed willow cuttings cultured in vitro and the appearance of vitreous plants has been studied. By using two basal media (Murashige and Skoog medium and Knop medium half diluted) an in vitro culture scheme has been developed which allows the control of the vitrification process by varying the nitrogen supply in the culture media. The results obtained agree that the vitrification of the cloned plants is directly associated with the ammonium content of the culture medium. In vitrified plants, lignin content of the shoot is reduced by 50%. Correlatively, histological controls at different levels of the shoot of the plantlets show that the reduction of the xylem tissue can reach 70%.