458 



SUBJECT INDEX 



Spore germination — continued 



effect of hydrogen sulphide, pentathionic acid, 



sulphuric acid, 362-366 

 of Lycopodium, 434-435 

 temperature and time effects, 372 

 Spores, fungus: induced in Alternaria solani cul- 

 tures, 377 

 Sporobolus, 35 



Spray residues: on apples, 355 

 Sprouting: of dormant potato tubers, 230-240 

 Stachys, 29, 30, 34 

 Statistical analysis of germination data: spores, 



369-374 

 Statistical methods: experimental design, 437-439 

 Stellaria, 34, 43 



Storage effects: (See Carbon dioxide storage effects) 

 Storage of potato tubers: effects on starch and 



sugar content, 240 

 Storage of seeds: {See Seed storage) 

 Stratification effects on germination: (See Germina- 

 tion of seeds: stratification effects) 

 Strawberry bvish: (See Evoyiymus) 

 Sucrose: changes in potatoes treated with chemi- 

 cals that break rest period, 251 

 storage temperature effects on potato tubers, 

 392-394 

 Sucrose in potato tubers: carbon dioxide effects, 

 395-397 

 storage temperature effects, 3SS-389 

 Sugar: in potato tubers, 251 



Sugar, cane: storage temperature efTects, 389, 390 

 Sugar, cane, in potato tubers: storage temperature 



effects on de-sugaring, 392 

 Sugar, reducing: analytical methods for determina- 

 tion, 437 

 storage temperature effects on potato tubers, 

 392-394 

 Sugar, reducing, in potato tubers: amount afTects 

 color in potato chips, 3S6-394 

 carbon dioxide effects, 395-397 

 storage temperature effects, 388-389 

 storage temperature effects on de-sugaring, 389- 

 392 

 Sugars: changes in relation to respiration rate, 249- 

 251 

 (See also Sucrose; Sugar, reducing; Sugar, cane) 

 Sulphur: method of making colloidal sulphur by 



distilling flowers of sulphur, 353 

 Sulphur compounds effects on: dormant potato 



tubers, 234 

 Sulphur dioxide: apparatus for studying effects on 

 plants, 186-187 

 environmental factors affecting injury to plants, 



189-191 

 in air at Boyce Thompson Institute, 190-191 

 Sulphur dioxide effects: injury to plants from smelt- 

 ers, 186-188 

 nutrition of plants, 191 

 on animals, 191-193 

 on plants and animals, 197-200 

 on soils, 427-428 

 toxicity to plants, 185-191 

 Sulpliur fungicides: action, 362-366 

 Sulphuric acid effects on: dormancy in seeds, (See 



Dormancy in seeds) 

 Sunlight: energy value per acre, 286-287 

 Sweet pea, 217 



Symphoricarpos, 106, 112, 129 

 Symphoricarpos orbiculatus: 122 

 embryo dormancy, 109 

 germination of seeds, 108-109 

 Symphoricarpos racemosus, 112 



Symphoricarpos racemosus seeds: after-ripenmg, 

 107-108 

 dormancy, 107-108 

 germination, 107-108 

 morphology, 107-108 

 Symplocos paniculala, 181 



Syringa vulgaris: chemical changes in leaves during 

 period preceding frost, 412-414 



Xalc effects: on germination of seeds, 419 

 Taxodium, 91 

 Taiodium distichum, 102 

 Taxus cuspidata, 112 



Telluriuin: toxicity compared to sulphur, 365-366 

 Temperature: {See Thermoperiodism effects) 

 Temperature effects on: after-ripening of epicotyl, 

 113-123 

 anthocyanin development, 320-321 

 dormancy, (See Dormancy) 

 lily bulb dormancy, 431 

 plants, 328-330 

 stored pollen, 429-430 



transpiration of plants in infra-red, light, 328-330 

 yarovization of .seeds, 333-334 

 Temperature, low: on flowering of biennials, 333-337 



on flowering of bulbous plants, 337 

 Tenehrio molitor: pyrethrum toxicity, 346-347 

 Tergitol 7 penetrant with j3./3'-dichloroethyl ether: 



Japanese beetle larvae control, 356-357 

 Tetranychus bimaculatus, 351 



Telraiiychus telarius: naphthalene toxicity, 352-353 

 Thallium sulphate: toxicity in soils, 428—429 

 Thea, 33 

 Thermoperiodism effects: on flowering of Digitalis 



purpurea, 334-337 

 Thiocyanates: hastening sprouting of dormant po- 

 tato tubers, 231-233 

 Thiocyanogen compounds: as insecticides, 351 

 Thiourea: as an antioxidant, 235-238 



hastening sprouting of dormant potato tubers, 



234-235 

 prevents browning of plant tissues and juices, 

 235-238 

 Thiourea effects: on enzyme activities in potato 

 tubers, 250-251 

 toxicity to mammals, 236-238 

 Thlaspi, 34, 35, 40, 42, 43 

 Thrinax, 33 

 Thuja, 91, 102 

 Tilia americana, 112 



Tissues: acidification of salt solutions by plant tis- 

 sue, in relation to question of tissue isoelec- 

 tric points, 416-418 

 Tobacco mosaic: inactivation by ultraviolet, 323 

 Tomato: as affected by growth substances, 210-212 



effects of illuminating gas on roots, 173 

 Tomato foliage diseases: early blight, late blight 

 and leaf spot, 374-378 

 greenhouse method of testing fungicides, 374-378 

 Toxicity: pyrethrum, 346-351 



spore determination method, 369-370 

 Toxicity of fungicides: as related to the periodic 

 system of the elements in compounds, 380 

 slide-germination method, 369-370 

 toxicity curves, 370-371 

 toxicity surface, 370 

 Toxicity of insecticides: fatty acids and soaps, 344- 

 346 

 thiocyanogen compounds, 351 

 Toxicity to plants: illuminating gas, 172-180 

 mercury and mercury compounds, 180-185 

 sulphur dioxide, 185-191 

 Tracheae: penetration of contact insecticides, 343- 



345 

 Translocation: twin-leaf method of studying 



changes in leaves, 408-414 

 Transpiration: effects of light and infra-red on to- 

 bacco, 328-330 

 effects of radiation on, 328-330 

 Tree peony: seedling production, 113-117 

 Trees: diagnosis of artificial illuminating gas injury, 

 178-179 

 effect of illuminating gas, 172-176 



