Is ANNUAL REPORTS Ol DEPARTMENT 01 AGRICULTURE, 1951 
lina. Recent spread, especially in Georgia, was creating :i serious 
threat to commercial production in the Southeastern States, With the 
assistance of the Extension Service and the Farm Bureau, 171 meet- 
ings were held in 24 counties in the 3 States, with an attendan i 
6,612, representing farmer groups, instructors in vocational agricul- 
ture, <»l farm trainees, agriculture classes, and civic clubs. The pro- 
gram provided instruction and demonstrations in weevil eradication, 
control practices, and methods of preventing spread. The educational 
program was also extended to northeastern Texas, where infestations 
wen- recently found in areas of heavy sweetpotato production. The 
program aroused great interest among sweetpotato growers. Grower 
participation in the cooperative weevil-control program immedi- 
ately increased. 
Alternate inseetieide nontoxic to lutmatis developed for etmtntl of 
sweetpotato weevil 
A third insecticidal dust that may serve as an alternate to DDT or 
methoxychlor, and is rapid enough in toxic action to prevent oviposi- 
tion by sweetpotato weevils on sweetpotatoes in storage, consists <>f 
0.8 percent of piperonyl butoxide and 0.04 percent of pyrethrins in 
a suitable diluent. Adult- were killed 91 days after application. 
Oviposition in dusted sweetpotatoes was prevented for more than 2 
months in preliminary trials. This dust mixture is nontoxic i<> man 
and animal-, thus presenting no problem of toxic residues. 
Systemic Insecticides Make Pea Plant:- Toxic to Pea \phi<l 
Treating pea seeds or pea plants with either <>f two systemic in- 
secticides, n.a ;n i km liyl pyrophosphoramide or a i rialkyl thiophosphate, 
make- the plant- toxic to the pea aphid, according to results of pre- 
liminary experiments in the greenhouse and in the field at Madison, 
Wis. 
In the greenhouse octamethyl pyrophosphoramide was toxic bo pea 
aphids placed manually on pea plain- after the plants were sprayed 
with a solution of the chemical. Plants growing from seeds planted 
in soil soaked with the solution just before planting, and those grow- 
ing from seeds treated directly with the solution before planting, also 
showed toxicity to aphids. 
Pea plants sprayed in the field with solutions of octamethyl pyro- 
pho phoramide were highly toxic to the pea aphid. The solutions 
were applied with a mist blower at rates of 0.2a and 0.5 pound of the 
chemical an acre in 10 gallons «»t' water. Treatment of p* a seeds with 
either octamethyl pyrophosphoramide or a trialkyl thiophosphate 
controlled the pea aphid on the resulting plants for approximately 6 
- in a season when the infestation was very slo\* in developing. 
I'.. i results were obtained when solutions of the chemicals were ap- 
plied to pea seeds at the rate oi 500 grams, or approximately ' pound, 
i" I bushels of seed, a quantity sufficient to plant l acre. Plants de- 
veloping from treated seeds, as well as those that were sprayed, 
-!k»\\ ^'i\ no foliage injury. 
The experiment were conducted in cooperation with the \\ sconsin 
A gricult ura I Experiment St at i< 
11 tamethyl pyrophosphoramide and a trialkyl thiophosphate are 
ned within treated plan'- for some time. Consequently, they 
