- 56? - 
Control may "bo effected by nicotine sulphate dust or a spray 
containing nicotine. 3*ring to the roughness of the ground and the 
difficulty of transporting v/atcr, ducting seems more practical on 
-.-at rmelons. Instructions are given to growers for making their 
o--n dust, thus effecting considerable reduction in the cost. A 
3 percent dust, v/hich is commonly used, requires 7.5 lb. 40-percent 
nicotine sulphate to 92.5 lb. lime or 6 lb. 50-percent free nicotine 
to 94 lb. lime. A 2 percent dust made rath 50-percent free nicotine, 
no, 'ever, is equivalent in effectiveness to a 3 percent dust made 
-./ith 40-percent nicotine sulphate, and it is therefore cheaper to 
make the dust -jith free nicotine. 
SIUPSOST, G, 7. (0347) 
1932. SPhAYIhO ^ITD DUSTING EXFZTJi.3JMTS F03 EC CGHESQL 0? POTATO APHID 
Jour. Soon. Sr.t . 25 (3): 634- -639. [Abstract in Itev. Appl. 3nt. (a) 
20: 502. 1932.] 
A series of tests -ras corducted to determine the relative toxicit 
of various mixtures containing nicotine sulphate and the mechanical 
efficiency of spraying and dusting practices against aphids on potatoes 
Dusting vrith a canvas trailer -fas more effective than spraying. Sprays 
containing potash fish-oil soap \70ro consistently more satisfactory thar 
any others tested. Ponotrol and nicotine together gave better results 
then •.hen added to bordeaux mixture. 
3.. Homoptora, 1921-1934 
a. Aphids, 1921-1934 
COAT, I. P. (2348 ) 
1923. DUSTIPG FCA THE PZA APHIS. "Jour. Scon. Ent. 16: 81-84. [AbstraJ 
in Pov. Appl. Int. (a) 11: 226. 1923.] 
Of all the materials tested for the control of the pea aphid 
(^ cyrthsiphon pi si Kalt.) only nicotine can be relied upon to give satii 
factor;.- results. High nicotine content is preferable to lou content anc 
not less than 30 lb., of nicotine dust should be used to the acre. Dustii 
should be done in. calm uoathcr, good results being obtained at tomporatj 
bove 70° P. The maximum effect may be obtained "oy the use of a trailei 
canvas. 
AVAIKIH, ff. H. (2349) 
1927. MOSAIC OF PlASPSZATJES. IT. V. (Geneva) Agr. Expt. Sta. Bull. 543 
SO pp., illus. [Abstract in Aev. Appl. Ent. (A) 15: 598-600. 1927.] 
Tests -.vith insecticides against aphids (Amphorophora rubi) 
indicated that a spray consisting of 8 lb. fish-oil soap, 1 pt. nicotin 
sulphate end 100 gal. uator r. r as more effective than a dust containin - 
ii rcent nicotine sulphate, but the aphid population was not material 3H 
reduced very long by either material. In other tests, 2' and 3 percent J 
nicotine dusts practically eliminated A. rubiphlla , but had little 1. :: ti 
effect on A. rubi; and sprays of 1 or 2 percent ^hito neutral oil cmuls! 
fied in uaTTcr with casein-lime failed to kill all the adults of A. rubi. 
