1922] CURRENT LITERATURE 333 
inoculated appeared to be more or less susceptible to the pink root organism, 
but other liliaceous plants, such as Funkia, Tulipa, Calla, Iris, and Lilium were 
immune. Pink root of onions has been observed in California, Iowa, Wisconsin, 
New York, and the Bermuda Islands. In Texas it seriously threatens the 
industry of growing onions for the early northern markets, which industry has 
_ an important one. Losses vary from $150 to $400 per acre. 
mptoms of pink root include yellowing of the roots, followed by their 
pink icin. drying, and death. The bulb exhausts its energy in produc- 
ing new roots. Alkali soil, deficiency in nitrogen and humus, excessive tempera- 
tures, eel worm and thrips attacks are factors favoring the disease. The 
seed is not a carrier, but onion “‘sets,’’ both dry and green, may harbor the 
causal fungus. . Suggested control methods include the use of virgin soil for 
seed bed and field plantings, steam or formaldehyde disinfection of seed beds 
known to contain the pink root fungus, rotation of crops, the use of quickly 
acting fertilizers, careful use of tools, and various cultural practices favoring 
continued growth of the crop. An attempt to control nematodes by adding 
cyanimide to the soil ae because the amount required to affect nematodes 
killed the crop. ant G. Brown. 
Carbon nutrition.—Storage rot fungi of the sweet potato have been 
investigated by WetrmerR and Harter, who find that seven of eight species 
causing rot can utilize glucose as a source of carbon. Five of them are able to 
increase the acidity of the culture medium, and certain species increased the 
osmotic concentration of the substratum. The glucose is utilized partly as a 
source of energy, partly in producing mycelium, and perhaps in still other ways. 
The respiratory activity of these organisms has been studied by the same 
authors,?7 who used the amount of CO, set free as the measure of the carbo- 
“hydrate used in this process. Penicillium sp., Botrytis cinerea, and Sclerotium 
bataticola grew slowly, produced relatively large amounts of dry material, 
consumed nearly all of the glucose, and produced CO, most freely. The 
other species grew more rapidly, but produced comparatively small amounts 
of CO, and did not consume all the glucose. The economic coefficient was 
found unusually high in two species. Fusarium acuminatum required 17.11 G. 
and Mucor racemosus 22.86 G. glucose for each gram of dry matter grown. 
The CO, set free is not equal to the theoretical amount that could have formed 
from the sugar consumed. Some of the sugar evidently was not completely 
respired, as alcohol and acids appeared in some of the culture solutions.— 
C. A. SHULL. 
Transmission of potato wilts.—Among the various wilts which are respon- 
sible for heavy losses sustained by potato growers are those due to attacks of 
6 Weimer, J. L., and Harter, L. L., Glucose as a source of carbon for certain 
sweet ‘etal storage rot fungi. Jour. A ok Res. 21: 189-210. 1921. 
——, Respiration of sweet potato storage rot fungi when grown on a nutrient 
solution. Jour. Agric. Res, 21: 211-226. 1921 
