CONTENTS 



JPAGB 



Part I. Effect of inorganic compounds on root growth ■. 78 



Effect of nutrient solutions 78 



Influence of treatment with potassium permanganate 79 



Reasons of stimulation 88 



Possible effect on food supply 88 



. Relation to rest period 88 



Effect on rest period of twig as a whole 88 



Effect on rest period of basal part 91 



Stimulation of root growth in twigs that have passed the rest period 92 



True rest shown only by buds of woody cuttings 93 



Possibility that a treatment affecting the rest period may at the same time 



affect root growth 94 



Effect of treatment on correlation between tops and roots 95 



Effect of treatment on respiratory activity 97 



Effect of treatment on growth of microorganisms 100 



Comparison of the effect of potassium permanganate with that of other manganese 

 compounds, and also with that of iron, of aluminium, of boron, and of 



phosphorus 104 



Experiments with herbaceous cuttings 104 



Experiments with woody cuttings 110 



Continuous treatment 110 



Limited treatment 110 



Discussion of stimulation by compounds other than potassium permanganate Ill 



Manganese Ill 



Iron and aluminium 114 



Sulfur 114 



Boric acid 115 



Phosphates 115 



Part II. Organic nutrition of cuttings 116 



Review'of literature 116 



■^iffect of limited treatment with sugar solutions on immature twigs 117 



Treatment with different concentrations 117 



Treatment for one day, for two days, and for twelve days 118 



Influence of solutions of sugar for one, five, and fourteen days, respectively, in 



an incubator 1 20 



Effect of continuous treatment with sugar solutions 121 



Effect of sugar alone on immature twigs -121 



Effect of sugar with manganese dioxide, boric acid, or ferric chloride 122 



Effect of Umited treatment with sugar solutions on maturer cuttings 123 



Forcible injection of sugar solutions 125 



Discussion 126 



Part III. General discussion with reference to practices commonly followed by green- 

 house and nursery men 129 



Summary 133 



Acknowledgment 134 



Bibliography 135 



71 



