164 • Subject Index 



SDP, see Short-day plant(s) 



Seasonal control, by cold treatments, 

 54-55, 129; bv photoperiodism. 10- 

 13, 15; by water, 129-130 



Seasonal flower initiation and develop- 

 ment, 7 



Seed germination, 34-35, 57 



Sex expression, and auxin. 132-133; 

 and gibberellin. 133; and photo- 

 periodism, 131-132; and tempera- 

 ture, 131 



Sex hormones, animal. 133 



Short-day plants (SDP) definition, 13; 

 inhibition by long days in. 25; see 

 also Critical davlength 



Short-long-day plants, 13-14. r>l-62 



Temperature, effects of, on bulb 

 plants, 64-66 — on critical daylength, 

 26. 43 — on endogenous circadian 

 rhythms, 42-46, 52 — on photoperiod- 

 ism, 25-27 — on red, far-red system, 

 34, 36-37 — on sex expression, 131; 

 high, devernalization by, 60-61; 

 interactions with light and dark 

 periods, 25-27, 63-64; see also Cold 

 requirements; Cold treatments; Ver- 

 nalization 



Thermoperiodism, 25-27, 63-64. 131 



Trees, see Perennials, woody 



2,3,5-Triiodobenzoic acid (TIBA), 107- 

 109, 132-133 



Tropical plants, lack of cold require- 

 ments in bulbs, 65-66; lack of 

 knowledge about, G; water effects on 

 seasonal anthesis, 129-130 



Ultraviolet radiation, 90 

 United States Department of Agricul- 

 ture, 11-13,32-39 



Vegetative growth, effects on, of cold, 

 vernalization, 57, 59-60, 64 — of light 

 quality, 39 — of photoperiodism, 27- 

 28, 122-123; and gibberellin (stem 

 elongation), 100-105; relation to 

 flower development and initiation. 

 8-9, 28; restraint of, 111; see also 

 Age; Bolting; Meristem 



Vernalin, 82-83 



Vernalization, and auxin, 118; and 

 carbohydrates, 57, 60-61; definition 

 and qualifications, 55, 58, 62-64; 

 induction by, 56-57, 87-88; and 

 political ideology. 55; see also Cereals, 

 winter and spring; Cold require- 

 ments; Cold treatments; Devernali/a- 

 tion; Vernalin 



Viruses, 78, 92 



Vitamin E, 110 



Water, 129-130 



Woody plants, see Perennials 



X-rays, 90 





