Histological Responses of Cabbage Plants Grown at Different Levels of Nitrogen Nutrition to Indole(3)Acetic Acid

Abstract

Application of a 3% mixture of indoleacetic acid in lanolin made to decapitated first internodes of very young cabbage seedlings caused the development of an apical callus and a crown of adventitious roots. These roots were derived mainly from the rays and phloem. About J of the plants produced viable shoots, either directly from the top of the callus or laterally at about the level of adventitious root production from the cortex and rays. Woody plants grown with little N available react much more slowly and to a lesser extent than do those grown with a large supply. The former produce a much smaller and more highly vascularized callus, through which the root primordia rarely protrude.