ioiS 
Journal of Agricultural Research 
Vol. XXII 
Page 
Potassium— 
salts, effects on wheat at different stages of 
growth.•. 57-62 
sulphates and chlorids, relation to sand 
drown of tobacco. 28-29,30-35 
Potato— 
corticium vagum , pathogenicity, relation to 
soil temperature. 761-770 
Early Ohio, testing for permanence of char¬ 
acters..... 950-958 
permanence of variety.947-963 
plant, effect of selection and environment, 
tests.950-958 
tuber rot, caused by Sclerotium rolfsii, de¬ 
scription . 45-46 
Potatoes- 
diseases, literature citations. 967 
growing, relation to temperature and length 
otday....889-890,891-893 
inoculation witli Sclerotium rolfsii t results.. 41-44 
Sclerotium rolfsii parasitism. 41-46 
seed, selection methods. 948 
skinspot, relation to powdery scab.285-394 
varietal improvement, method.949-950 
variety, senility, discussion.947-949 
wart, anatomical studies.963-968 
Powdery scab, relation of potato skinspot.. 285-294 
Power, Frederick B., and Chesnut, Victor K: 
Examination of Authentic Grape Juices for 
Methyl Anthranilate.47-53 
Probable Cause of the Toxicity of the So- 
Called Poisonous Greensand: j. W. Kelly 223-228 
Production and Dispersal of Conidia in the 
Philippine Sclerosporas of Maize: William 
H. Weston, jr.339-278 
Production of a Growth-Promoting Substance 
by Azotobacter: O. W. Hunter.825-831 
Protein- 
content in wheat and flour, correlations.... 531 
flour content, relation to wheat protein.... 531 
wheat content, relation to flour charac¬ 
ters. 53 *> 534”538 
Protopine, alkaloid in Bikukulla spp. 71-76 
Pubesence, relation to length of day. 900 
Puccmia — 
grammis tritici. See Stem rust, wheat, 
spp., action upon immune hosts, studies 
and discussion. 132-133,139-149 
Pycnidia— 
development studies. 743-744 
fruit fungi, cavities, origin. 743-760 
Rabbits, anthelmintics, tests of carbon tetra- 
chlorid. 167-168 
Radishes— 
growing, experiments with daylight of dif¬ 
ferent lengths.887-888,896 
mulching, effects and cultivation. 736 
Rape, seed, content of iron and manganese. 398,399 
Rats, white, feeding experiments with dried 
Azotobacter cells.826,828 
Redtop, seed germination temperatures. 296, 
297,299-300,322 
Relation of Potato Skinspot to Powdery Scab: 
Michael Shapovalov. 285-294 
Respiration, experiments calculation, formu¬ 
la, and recording. 109-113 
of Apple Seeds: George T. Har¬ 
rington. 117-130 
Respirometer, for seeds and other small ob¬ 
jects, directions for its use. 101-116 
Rhamnose, determination in com plant... 659,660 
Rheum rhaponticum. See Rhubarb. 
Rhubarb— 
diseases, description, and weather relations. 3-5 
footrot, Phytophthora. 1-26 
infection with footrot organism, symptoms, 
and results.3-4/6-9 
Rhus spp., growing, experiments with day¬ 
light of different lengths.903-904 
Rice 'weevil, control by parasite, Aplasto- 
morpha vandinei . 549-556 
Richards, B. I,.: Further Studies of the 
Pathogenicity of Corticium vagum on the 
Potato as Affected by Soil Temperature.. 761-770 
Robinson, T. Ralph, and Swingle, Walter T.: 
Two Important New Types of Citrous Hy¬ 
brids for the Home Garden—Citrangequats 
and Eimequats. 229-239 
Page 
Root growth, relation to length of day. 900 
Rootrot, cotton, in Arizona. 525-527 
Rootrots, com— 
effect of soil treatment. 806-807 
relation to aluminum and iron compounds 
in com plant.801-824 
resistance, relation to selective absorption 
of salts.803-804 
Roots— 
com, pentosan content.657,658 
thickening, relation to length of day and 
night.889-898 
Rosette— 
disease, wheat, cause and control. 771-800 
wheat— 
cause, studies. 778-788 
spread, method investigations. 789 
symptoms. 775-77* 
Rot, strawberry, fungus, pycnidium cavities, 
origin. 748-750 
Rots, com— 
cuased by parasitic internal fungi, investi¬ 
gations. 495”52* 
effect on plant vigor and yield of grain... £83-630 
roots and stalks, relation to iron and alumi¬ 
num compounds.801-824 
Rust- 
grain, studies and literature concerning.. 131-133» 
. . * 49 -i 5 i 
tobacco, cause, names, description. 481-494 
Salts, ammonium, calcium, magnesium, po¬ 
tassium. 57-62 
Sand Drown, a Chlorosis of Tobacco Due to 
Magnesium Deficiency, and the Relation oi 
Sulphates and Chlorids of Potassium to the 
Disease: W. W. Gamer, J. E. McMurtrey, 
C. W. Bacon, and E. G. Moss. 27-40 
Sand drown— 
comparison with other types of chlorosis... 35-36 
tobacco, biochemical studies.30-35 
Scab— 
powdery, relation of potato skinspot. 285-294 
wheat, infection of com seed, effect on yield 
of grain. 587-604,632-627 
Schizoparme straminea, cause of strawberry 
disease, study of pycnidium. 750-757 
Sclerospora — 
pktlippinensis . 239-278 
spontanea . 239-278 
Sclerosporas, Philippine, of maize, conidia, 
production and dispersal. 239-278 
Sclerotia, lettuce drop, control by formalde¬ 
hyde. 646-647,648-652 
Sclerotinia carunculoides, the Cause of a Se¬ 
rious Disease of the Mulberry (Morus alba): 
Eugene A. Siegler and Anna E. Jenkins. 833-836 
Sclerotinia — 
libertiana — 
cause of lettuce drop. 645 
treatment of sclerotia and mycelium with 
formaldehyde. 646-652 
ricini, cause of gray mold of castor bean.... 688- 
702,713 
shiraiana, cause of mulberry disease in 
Japan.834-835 
Sclerotiopsis concava, fungus causing straw¬ 
berry rot, studies. 748-750,754,756 
Sclerotium rolfsii, parasitism on Irish pota¬ 
toes.41-46 
Sedges, pasture, burning and its effect.635-636 
Seed- 
bed, conditions, relation to germination of 
grain...86-87,96 
castor-bean, treatment for control of gray 
mold. 711-7x2 
com— 
fungi internal of.495-524 
infection methods. 520-522 
relation of infection to early vigor of plants 
and yield of grain. 587,591-626 
cotton, spread of wilt organism.387-393 
germination, bibliography... 97-100 
grain— 
heating and presoaking, effect on germi¬ 
nation.83-85,96 
sterilization with nitrate of silver.85-86 
infected, cause of seedling blight of com and 
wheat.840,868 
