6i6 



Journal of Agricultural Research 



Vol. xvin 



Quack grass. Stc Agropyrumrepens. Page 



Radish. See Raphanus sativtis. 



Ragweed. See Ambrosia artemisiifolia. 



Raphanus salivus — 

 efiect of relative length of day and night. 565-566 

 hostof 5c/eroiiMm rolfsii 127 



Rate of Absorption of Soil Constituents at 

 Successive Stages of Plant Growth (paper). 51-72 



Recent Studies on Sclerotium rolfsii Sacc. 

 (paper) 127-138 



Reducing sugar in potato tubers attacked by 

 Pytkium debaryanuTn 277-278 



Relation of Moisture in Solid Substrata to 

 Physiological Salt Balance for Plants and to 

 the Relative Plant-Producing Value of Va- 

 rious Salt Proportions (paper) 357-378 



Relation of the Concentration and Reaction 

 of the Nutrient Medium to the Growth and 

 Absorption of the Plant (paper) 73-117 



Reproduction, plant, effect of relative length 

 of day and night 572-578 



Response of Citrus Seedlings in Water Cul- 

 tures to Salts and Organic Extracts (paper). 267- 



2 7-4 

 Reticuliierm.es sp., expeiimental host of Soro- 



spotella uvella 432 



Rkeum rhaponticum, host ol Sclerotium rolfsii. 129 

 Rhizopus ■nigricans, efiect on sugar content of 



host 277 



Rhodopkora gaurae at light traps 477-481 



Rhopalosiphum — 

 padi. Syn. Rhopalosiphum prunifoliae. 

 prunifoliae — 



egg 311-312 



fall migrant 320-321 



feeding of ovipara 3 23-324 



male 321-322 



ovipara 321 



oviposition 323 



sexes 322-323 



spring alate form 314 



spring apterous form 314-31S 



spring migrant 315 



stem mother 312-314 



summer alate form 319 



summer apterous form 317-319 



summer intermediate form 319 



Rhyssalus oscinidis, parasite of Agrom,yza me- 



lampyga 472 



Roberts, Herbert F. (paper): Yellow-Berry 



in Hard Winter Wheat 155-169 



Rootrot of cotton 305-310 



Rose-apple. See Eugenia jambos. 



Rye. See Secale cereale. 



Rye grass. See Elymus canadensis. 



Sacchaium officinarum, host of Sclerotium 



rolfsii 129 



Salmon, S. C, et al. (paper): Losses of Or- 

 ganic Matter in Making Brown and Black 



Alfalfa 299-304 



Salts- 

 alkaline, toxic limits 271 



effect on citrus seedlings in water cultures. 267-2 74 

 Satin-leaf. See Chrysophyllum olivaeforme. 



Schinia marginaia at light traps 477-4S1 



Sclerotinia — 

 frucligenia, effect on sugar content of host. . 277 

 libertiania — 



method of attack on cells 275 



resemblance to Sclerotium rolfsii 135 



Sclerotium. rolfsii— Page 



hosts 128-129 



mode of infection 132-133 



period of incubation 132 



racial strains 129-131 



sexuality 136 



symptoms 133-13S 



Scofield,C.S. (paper): Cotton Rootrot Spots. 305-310 

 Secale cereale — 



germination of pollen 526 



host plant of Oscinis frit 471 



Sedge. See Cyperus strigosus. 

 Seedlings- 

 citrus, response to salts and organic ex- 

 tracts 267-274 



wheat, effect of lime on sodium-chlorid 



tolerance 347-356 



Seeds, cereals, treatment by dry heat 379-390 



Shapovalov, M., and Edson, H. A. (paper): 

 Temperature Relations of Certain Potato- 

 Rot and Wilt-Producing Fungi 511-524 



Shedd, O. M. (paper): Effect of Oxidation of 

 Sulphur in Soils on the Solubility of Rock 



Phosphate and on Nitrification 329-34S 



Shive, John W. (paper): Relation of Moisture 

 in Solid Substrata to Physiological Salt 

 Balance for Plants and to the Relative 

 Plant-Producing Value of Various Salt 



Proportions 357-378 



Silage- 

 corn, comparison with sunflower silage. . . . 327 



sunflower 325-327 



Silkworm. See Bombyz mori. 

 Simple Method for Measuring the Acidity of 

 Cereal Products: Its Application to Sul- 

 phured and Unsulphured Oats (paper) .... 33-49 



Sirup, sorghum, composition 1-31 



Slender wheat-grass. See A gropyrum teiterum. 

 Slough grass. See Spartina michauxiana. 



Smut, effect of dry heat 390 



Sodium — 



bicarbonate, effect of — 

 calcium oxid on toxicity to wheat seed- 

 lings 353 



magnesium sulphate on toxicity to wheat 



seedlings 353 



potassium chlorid on toxicity to wheat 



seedlings 353 



sodium nitrate on toxicity to wheat 



seedlings 353 



carbonate, toxicity to citrus seedlings. ..... 271 



chlorid — 



in poultry rations 394 



tolerance of wheat seedlings, effect of 



lime 347-356 



hydrate, toxity to citrus seedlings 271 



nitrate — 

 effect on 

 sodium-bicarbonate tolerance of wheat 



seedlings 353 



sodium-chlorid tolerance of wheat 



seedlings 352 



sodium-sulphate tolerance of wheat 



seedlings 353 



toxic limits 272-274 



phosphate, efiect on sodium-chlorid toler- 

 ance of wheat seedlings 352 



