162 • Subject Index 



light quality. 37-39; and red, far-red 

 system, 37-40; and temperature. 25, 

 43; see also Light and dark periods; 

 Photoperiodism 



Critical nightlength, see Critical day- 

 length 



Crown -gall, 97 



Cumulative-flowering plants, 7 



Dark periods, see Light and dark 



periods 

 Darkness, see Light and dark periods 

 Daylength, see Critical daylength 

 Daylength-indifferent plants, definition, 



14-15; florigen production by, 72; 



genetics of, 134; nutrition and flower- 

 ing of. 112-113 

 Dayneutral, see Daylength-indifferent 



plants 

 Devernalization, by gibberellin, M)l; 



by high temperature, 60-61; of 



perennials, 60-61 

 2,4-Dichlorophenox\ acetic acid (2,4-D), 



107-108 

 Diffusate, 110-111 

 Direct-flowering plants, 7 



Endogenous circadian rhythms, and 

 action of light-breaks, 47-50; as basis 

 of photoperiodism, 42-44. 46-47, 52- 

 53; and leaf movements. 44-45, 50; 

 and light and dark period inter- 

 actions, 51-53; and red. far-red sys- 

 tem, 52; temperature effects on, 42- 

 46. 52; in timing of anthesis, 127- 

 129 



Ethylene. 108 



Eloral hormone or stimulus, see Flori- 

 gen 



Florigen, activity, criteria of, 99 — of 

 natural extracts. 109-110; concept 

 examined, 78-82, 95-98; evidence for 

 existence, 69-72; production by day- 

 length-indifferent plants, 72; relation 

 to induction, 85-87; transfer across 

 grafts, 69-72, 82, 84-85, 125; trans- 

 location, and carbohydrate trans- 

 location, 72-77— rate of. 77-78 



Flower development and initiation, re- 

 lation to vegetative growth, 8-9, 28; 



relations between, 6-7, 87, 94; sea- 

 sonal occurrence of, 6-7, 10, 12, 54, 

 129-130 

 Flower opening, see Anthesis 

 Flowering hormone or stimulus, see 



Florigen 

 Furfuryl alcohol. 109 



Genetics of flowering responses, 134- 

 136 



Gibberellin, devernalization by, 101; 

 effects on short-day plants, 104-105; 

 inhibition of flowering, 104-105, 126; 

 long-day plants, 91, 101-104; promo- 

 tion of bolting and flowering, 100- 

 104, 137; promotion of staminate 

 development, 133; and red, far-red 

 system, 100; satisfaction of cold re- 

 quirements. 100-102, 104, 118; and 

 vegetative growth, 100-104 



Girdling, 123-124 



Grafts, ambiguous effects on flowering, 

 79-82, 125; on dwarfing stocks, 124; 

 transfer of florigen across, 69-72, 82, 

 84-85, 125; transfer of induced state 

 by, 84-85; transfer of vernalin 

 across, 82-83 

 Gravity, 90-91, 124 



Hormone, definition. 67; floral or 



flowering, see Florigen 

 ^-Hydroxyethvl hydrazine, 108 



Indirect-flowering plants, 7 

 Induced state (Induction), and auxin, 

 89-91; by cold, vernalization, 56-57, 

 87-88; compared to crown-gall 

 tumor. 97; defined, 17; fractional, 

 24-25, 88; inhibition by dark periods 

 in SDP, 20-22; and nucleic acids. 

 92-93. 96; permanence of, 83-8S; 

 quantitative nature of, 87-88, 94-95; 

 transfer across grafts, 84-85; and 

 vegetative growth, 28 



Induction, see Induced state 



Inflorescence. 2 



Iron, 113-114 



Juvenility, and carbohydrate, 96, 125; 

 in woody plants, 116. 124-126; see 

 also Age 



