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OUTRIGHT, C. R. (2233) 
1930. APPLE APHID S IN OHIO. Ohio Agr. Expt. Sta. Bull. 454, 59pp., 
illus. [Abstract in Rev. Appl. Ent. (A) 19: 202-203. 1931.] 
The spray tests deal with Aphi s pom i DeG. , Anur aphis roseus Bak. 
and Rhop alosip hum p runifoliae Pitch. Lime-sulphur to which nicotine 
sulphate had been added, gave the "best results against the eggs. The 
addition of nicotine to oil sprays did not give an increased efficiency 
sufficient to justify the extra, cost. In laboratory tests against young 
stem mothers, sprays in which oils (2 percent) were used as spreaders 
or as liberators of nicotine sulphate gave the best results. Of a 
number of derris products, only derrisol at 1 to 800 gave satisfactory 
results, and nicotine sulphate was equally effective at a lower con- 
centration and. cost. Field tests showed that the addition of nicotine 
sulphate in proportions of from 1 to 400 and 1 to 800 to the late 
dormant lime-sulphur sprays considerably increased their effect. The 
strength of the nicotine is of greater importance in control than is 
that of the lime-sulphur. 
In laboratory tests with summer sprays against Aphis pomi, nico- 
tine sulphate, at 1 to 1,600, combined with 0.75 percent miscible oil or 
1 percent oil emulsion, gave the best results. In field tests 1 percent 
Volck oil was most effective with nicotine sulphate at 1 to 1,600. No 
injury to the foliage occurred and a mortality of 99.5 percent was ob- 
tained. Penetrol, used in laboratory tests at 1-percent strength com- 
bined with nicotine (1:2,000.) gave 1.00 percent mortality. 
HARTZELL, p. 2- (2234) 
1930. TOXICITY OP SPRAYS AND SPRAY INGREDIENTS ON PEAR PSYLLA NYMPHS. 
Jour. Econ. Ent. 23: 190-197. [Abstract in Chem. Abs. 24: 3311. 1930.1 
The toxicity of nicotine solutions to nymphs of Psylla pyri reached 
a maximum at a dilution of 1 to 3,200. The nicotine content of sprays may 
be considerably reduced if other toxic substances, which do not react un- 
favorably with the nicotine are added. These substances are: penetrol, 
white petroleum oils, pine oil , and a commercial neutral oil from the 
destructive distillation of wood. Penetrol in a spray containing 
bordeaux mixture and nicotine appears to be safe on foliage in the spring. 
HOSRNER, J. L. (2235) 
1930. PENETROL AS AN ACTIVATOR POR NICOTINE. Jour. Econ. Ent. 23: 174- 
177, illus. [Abstract in Rev. Appl. Ent. (A) 18: 403. 1930.] 
Penetrol gave consistently better results than potassium fish- 
oil soap as an activator for nicotine . The dilutions used were penetrol 
or fish-oil soap 1 to 400 and nicotine (50-percent) 1 to 10,000. The 
insects tested were Macro siphum (l. Iacrosiphoniella ) sanborn i Gill., Myzus 
persice.e Sul z . , and Aphi s spiraecola Pat ch . 
