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has "been demonstrated that these insecticides which do not leave 
residues objectionable from the standpoint of human health can be 
effectively used against a number of different truck-crop pests, 
such as certain cabbage worms and the Mexican bean beetle, and that 
they are effective against flea beetles destructive to growing 
tobacco. The further usefulness of these recently developed 
materials is evidenced 'ay the determination that one application 
of sprays or dusts of derris or cube is effective against the 
pea aphid over a longer period than other recommended materials 
such as pyre thrum and nicotine." 
Wille, Ocmpo, Tfebcrbauer, and Schofield (471), of the Agricultural 
Experiment Station at Lima, Peru, published a complete review of information 
on cube in 1937. Insects against which cube has proved effective are 
listed in their families and. also those against which it is ineffective. 
In tests against the chief pests of cotton in Peru, sprays of cube extract 
containing 0.05 or 0.01 percent rotonone proved as effective against 
Aphi s gossypii Glov. as 0.5 percent nicotine sulphate. Dusts of ground 
cube root of 5 and 1 percent rotenone content gave 50 and 15 percent 
mortality, respectively, of adults of Anthononus ve.; 'i '-:s Boh. , in the 
laboratory. Sprays of cube extract of up to 0.05 percent rotonone content 
had no effect on larvae of Anomis luridula G-n. ( tcxana Riley) and Alabama 
argillacea Hbn. , but in another series of tests, a spray of 0.01 percent 
rotenone content gave 75 percent mortality after 8 days, and surviving 
larvae were unable to moiilt normally. A suspension of cube dust in water 
to give a spray containing 0.3 percent rotenone killed 73 percent of the 
larvae in 5 days, but was not effective in the field, probably owing to 
imperfect wetting. 
In laboratory tests against 30 adults of Pysder cus ruf icollis 1., 
a cube dust containing 5 percent rotenone killed 4 and paralyzed the others 
in 24 hours, and after 4 days, 19 were dead. Dusts of lower rotenone content 
also gave good results, one of 0.01 percent giving 80 percent mortality 
in 5 days. One unfavourable result of this slow rate of toxicity was that 
females were able to oviposit normally and their eggs hatched. Sprays of 0.1 
percent rotenone content in three tests gave 52, 80 ancL" 100 percent 
mortality, respectively. 
It is concluded that in Peru cube root and its products cannot 
replace the customary insecticides against plant pests. On the other 
hand, highly satisfactory results were obtained against parasites of 
domestic animals. 
Part of this publication deals with the ur,e of cube in dips against 
Melophagus ovinus L. and Sarcoptcs sp. on sheep, Haematopinus curysternus 
Nitzsch on cattle, H. suis L. on pigs, and a species of Psoroptes on 
alpaca in Peru. In 1935 more than 300,000 sheep were treated with cube 
dip in the Junin region, and 150,000 in that of Puno. The dips were 
obtained either from an extract prepared by soaking the chopped roots in 
water for 48 hours, or from a powder finely ground so that 85 percent 
passed a sieve of 0.074 mm. mesh. Their practical application was studied 
in 1936 by J. P. Mitchell, who stated that the powder yielded a dip that 
