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Phyllotreta vittata (7.) , the striped flea beetle 
Allen (9) in 1934 reported that a derris dust containing 1 
percent of rotenone and ea-ua.1 parts of finely ground tobacco dust, 
with 300-mesh dusting sulfur as a diluent, is very effective in control- 
ling the striped flea beetle. 
Easily killed by derris dust. — Hamilton and Gem-^.ell ( 174 ) in 1934. 
Killed by a derris-gypsum dust (0.4 percent of rotenone) — Herman 
and Hoclcey (lB5) in 1936. 
Oka-moto ( 309 ) in 1936 reported tha.t a derris insecticide is 
very effective for the control of this species, vrhich is very common 
on cruciferous vegetables in Japan. 
Agicide DC-4 (rotenone 0.6 percent) at the rate of 4 pounds per 
100 gallons of water (0.003 percent of rotenone in spray) killed from 
50 to 100 )ercent within 96 hours. — Agicide La.boratorios (0) in 1939. 
A l-percent-rotenone dust may be used for the control of the 
striped cabba.ge flea beetle with effective results if -the applications 
are thoroughly ma.de and rea.sonably frequent. The tendencr; is to begin 
the treatments too late, and injury is often severe before even an ex- 
perienced grower realizes it. — Crosby, Chupp, and Leiby (92) in 1939. 
Phyllotreta vittata discedens ^'eis e 
Tlie Louisiana Agricultural :H!xperiment Station ( 263 ) in 1938 re- 
ported tha.t a derris dust containing 1 percent of rotenone has given 
best results in the control of the striped flea beetle on turnips and 
mustard. If the dust is applied at v/eekl;- intervals as long as beetles 
are present, this pest can be controlled very effectively. 
Phyllotreta sp. 
Sensitive to derris dust. — DeBussy et al. (5l); also Van der L£>.an 
( 252 ) in 1936. 
Davies (98) in 1937 referred to experiments by Petherbridge and 
Thomas (317, 3187 in 1935 and 1936 with derris dust against flea beetles. 
Davies tested derris, derris plust slate dust (1:4), and other materials 
against turnip flea beetles, Ph/ll^treta sp. , on Svrede seedlings. Slate 
dust (10 percent of seedlings damaged) alone was about as effective as 
derris (l5 percent damaged) in protecting the plants. From 74 to 89 per- 
cent of the untreated plants were damaged. 
Plagiodera Inclusa, Stal , a soybean leaf beetle 
In the laboratory 30 adults were repeatedly dusted with laleur 
plusttalc 1:1, and Derris malaccensi s plus talc 1:1, and sprayed with 
derris "K.I." 0.5 percent in water (rotenone 1:2,850), ajid rotenone 
emulsion (1:2,000), according to Van der Scheer's procedure. The re- 
sult v:as not conclusive as 10 or more beetles of each group were still 
alive after three da.ys. Better results were obtained by feeding the 
