es (aie 
P. Re Fumigation Tests with Methyl Bromide. To determine 
usefulness and effectiveness of methyl bromide as a fumigant 
for control of insect pests of crops of Puerto Rico by deter- 
mining: (1) most economical and effective dosage for control 
of each insect species; (2) effect of fumigant on plant life 
when used at rates and methods needed for effective control 
of respective pests; and (3) practical means, if any, needed 
to insure safe and effective fumigation with methyl bromide. 
Ent. 73 
Rejilie A Study of Insecticide Resistance Exhibited by Various 
Insects of Agricultural Crops. To (1) determine various 
insect species showing resistance to insecticides under field 
conditions, (2) obtain fundamental information on nature of 
such resistance. (3) determine alternate control measures for 
insects developing resistance to specific insecticides. 
Ent., Jake Path., Chem. 606 
Tenn. Effect of Certain Insecticides and Herbicides Upon the 
Bio-Chemical Activities of the Soil and Upon Plant Growth. 
(1) Establish safe limits of concentration of newer types of 
insecticides that may be incorporated into the soil without 
adversely affecting microbiological activities in the soil. 
(2) Learn lethal concentration of insecticides for plant 
growth; and (3) duration of possible injurious effects from 
overdosages. 
Agron. 54 
Tex. Physiological and Biochemical Effects of Systemic Insecti- 
cides on the Cotton Plant. To (1) determine role of the plant 
in translocation, alteration, and persistence of systemic in- 
secticides, to better understand mechanics of distribution with- 
in plant of compounds involved; (2) investigate effect of sys- 
temics on plant development, defining dosage levels and condi- 
tions at which stimulation or phytotoxicity occurs; (3) deter- 
mine effect of systemics on plant's organic and inorganic nutri- 
tion in relation to their insecticidal effectiveness; and (4) 
attempt to develop a concept of alterations in chemical structure 
or systemics which contribute to increased or decreased phytotoxicity. 
Pile Physiol. and Path., Ent. 428 Coop. ARS 
Tex. The Mode of Action of Organic Insecticides as Related to 
the Nutrition and Metabolism of Insects. @) Rear selected in- 
sects on artificial diets as a means of learning their physiologi- 
cal and biochemical characteristics. (2) Study nutritive require- 
ments and metabolic reactions of insects on chemically defined 
diets. (3) Test known antimetabolites for their effects on meta- 
bolic reactions of insects. (4) Study effects of insecticides and 
correlate their actions with those of inhibitory substances. 
Biochem., Nutr. 790 Coop. ARS 
