-72- 
Qne of the more import* ^ uses of rotenone is to control the 
pea aphid.— Howard and coworkers (294 , p. 31). 
Mixtures of pyrophyliite, cube powder, and Black Leaf Dust 
Base exhibited a true synergistic relationship between the two toxi- 
cants. Host of the blends gave superior pea aphid control in exten- 
sive field tests. About 10 percent of dusting sulfur should be add- 
ed to the combination to reduce nicotine loss if the dusts are to 
be stored before use. Similar combinations with the addition of an 
aliphatic thiocyanate were also effective and showed still rreat- 
er economy of rot en one-bearing materials and nicotine. — Lilly (364). 
Suggestions for pea aphid control were published by the Eastern 
Pea Aphid Conference in March 1S43. Among the methods suggested 
were the following: (1) Use 3 pounds of derris or cube powder (4 
percent of rotenone) and 4 to 8 ounces of a wetting agent per 100 
gallons of water, applied at 125 gallons per acre; (2) Use a 0.5-per- 
cent rotenone dust mixture containing pyrophyliite or talc anri 1 per- 
cent of minerel oil, applied at 35 to 40 pounds per acre under a 25- 
foot apron; (3) Use a dust mixture containing 0.5 percent of rote- 
none, 2 percent of nicotine, and 10 to 25 percent of sulfur dilut- 
ed with pyrophyliite or talc; and (4) use a 0.5-percent rotenone dust 
mixture to which is added 2 percent of Lethane 60.— Pepper and co- 
workers (460 ) • 
The American Association of Economic Entomologists, at its 1941 
annual meeting, appointed a special committee on the insecticide 
supply situation, J. L. Horsfall, chairman. The committee reported 
that since rotenone materials were limited in 1943 one approach to 
the problem would be the use of mixtures of rotenone with thiocya- 
nates or nicotine added.— Horsfall and coworkers ( 288 ) • 
A dust mixture containing 0.375 percent of rotenone, 1.7 per- 
cent of nicotine, and 10 percent of sulfur was as useful as a mixt- 
ure containing 0.75 percent of rotenone.— U. S. Bureau of Entomology 
and Plant Quarantine ( 628 ) . 
Black Leaf 10 dusts containing 2 or 3 percent of nicotine in 
combination with 0.25 or 0.5 percent of rotenone fo ave about the same 
initial kill but had more residual effect than the 4-percent nico- 
tine dusts. Cube-pyrophyllite dusts containing 0.75 or 1 percent 
of rotenone were significantly better than those containing 0.2 or 
0.4 percent of rotenone. A 0.2- or 0.4-percent rotmone dust plus 
3 percent of Lethane 60 was as effective in controlling the pea aphid 
as any of the other dusts tested in Virginia. — 'Talker and Anderson 
(649). 
