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Serious cotton-aphid infestation in Peru can be prevented by- 
dusting with a mixture containing cube (0.75 to 1.5 percent of rote- 
none) and finely ground dusting sulfur*— Bibby (50). 
A dust containing equal parts of tobacco dust and sulfur with 
enough derris or cube added to give a 1-percent rotenone content 
gave satisfactory control if the plants were wet at the time of ap- 
plication. The addition of \ percent of rotenone to cryolite and 
barium fluosilicate reduced aphids by 88 and 76 percent, respective- 
ly, as compared with the calcium arsenate plots* Derris, cube, or 
nicotine sulfate, added to calcium arsenate dusts, in all cases pre- 
vented the development of damaging aphid infestation* Rotenone was 
superior to nicotine* Experiments in which 0*5 percent of rotenone 
was added to calcium arsenate were conducted at seven locations in 
six states* The data showed that this mixture was effective in keep- 
ing the aphid population at or below that in untreated check: plots 
and caused a significent increase in yield over plots treated with 
calcium arsenate alone* Derris, cube, and timbo were equally ef- 
fective as sources of rotenone* There were nighly significant dif- 
ferences in aphid control favoring the insecticides which contain- 
ed derris over those which did not*— Bondy and Rainwater (65-67); 
Rainwater (489); Rainwater and Bondy (491). 
Following eight effective dust applications, there were 3.6 
times as many ephids on cotton dusted with calcium arsenate plus 
0.5 percent of rotenone as on cotton treated with calcium arsenate 
plus 1 percent of nicotine.— Ewing and Moreland ( 173 , 174) . 
Caloium ar senate-rot en one prevented aphid increases better 
than calcium-zinc arsenate, but for yields the two mixtures were 
equally effective and better than calcium arsenate alone* In 1934 
and 1935 derris used alone or with sulfur seemed not to have in- 
creased the yield of cotton* In 1940-1942, however, when cube, 
derris, rotenone, or timbo was combined with calcium arsenate, or 
with arsenate and sulfur, the increase in yield was usually con- 
siderably over that for calcium arsenate, or arsenate plus sulfur* 
The special mixture of calcium arsenate, sulfur, and rotenone sig- 
nificantly controlled cotton aphids and increased the yield of 
cotton at Tallulah.— Gaines ( 210 , 212 ) ; Gaines and Dean ( 211) . 
Before the war good results had been obtained in controlling 
the cotton aphid by the addition of derris or cube to calcium 
arsenate, used for boll weevil control. The mixture contained 0.5 
percent of rotenone which was recommended for 1 year when war 
restrictions prohibited its use on cotton.— [Harned] (266). 
