STIMULATION OF ROOT GROWTH IN CUTTINGS BY 

 TREATMENT WITH CHEMICAL COMPOUNDS ^ 



Otis F. Curtis 



Increasing numbers of plants must of necessity be propagated vege- 

 tatively, either because of the difficulties involved in propagation by seed 

 or because many valuable forms do not reproduce true to seed. A large 

 proportion of such plants are started as cuttings, which when placed 

 under suitable conditions will develop into complete plants. In spite of 

 the very general use and importance of this method of propagation, nq 

 adequate investigations have thus far been made concerning the prin- 

 ciples or the factors involved. 



When the importance of propagating plants by cuttings is considered, 

 the value of any treatment that will stimulate root formation in cuttings 

 is obvious. Many special methods of treatment have been suggested. 

 For the most part these are based on practical experience, yet the reasons 

 given for the practices described are often directly conflicting or are not 

 well founded on physiological facts so far as these are known. It would 

 seem, therefore, that some definitely directed research in the physiology 

 of root formation in cuttings would be of value in this field. 



During some investigations to determine the effect of various chemical 

 compounds on the rest period of woody plants, conducted in the Labo- 

 ratory of Plant Physiology at Cornell University, it was found that when 

 twigs of Ligustrum ovalifolium Hassk. were treated for a short time with 

 a solution of potassium permanganate, roots developed to a greater extent 

 than on the checks or on twigs treated with other compounds. These, 

 results suggested the possibility of an investigation concerning the effect 

 of various chemical compounds on the root growth of cuttings, and this 

 has been the primary purpose of the present investigation. No experi- 

 ments have been conducted to compare directly the value of different 

 methods in common practice among propagators, as those methods cover 



1 Contribution from the Laboratory of Plant Physiology, Cornell University. 



75 



