Highest Number Of Survivors Research Articles

Tolerance of the stages of Stetborus punctum to selected insecticided and miticides.

The toxicity of 16 pesticides to all life stages of the predatory coccinellid Stethorus punctum (LeConte) resulted in a high number of survivors from all treatments except 0.50 lb active ingredient (AI) per 100 gallons of carbaryl WP 50%, and 0.1875 lb AI/100 gal carbofuran wp 75% when tested in an insectary. At the dosages tested, most other materials tested could be used in an integrated control program of apple pests with a high rate of survival of this predaceous arthropod.

Protective effect of 6-azathymine and 6-azauracil against the lethal effect of ultraviolet irradiation: II. Isolation of thymine photoproducts from the nucleic acids of Streptococcus faecalis

Streptococcus faecalis (ATCC 8043) grown in the presence of either [ 3H]thymidine or [2- 14C]thymine (8 μM) and a partially inhibitory concentration of either 6-azathymine (60 μM) or 6-azauracil (660 μM) showed, after ultraviolet irradiation (2537 Å), a 10-20-fold higher number of survivors than cells grown in a limiting concentration of either thymine or thymidine (4 μM). No significant difference was found between the various treatments in the amount of thymine dimer formed in the acid-insoluble fraction on irradiation. In addition to thymine dimer, a second photoproduct, occurring in smaller amounts was detected. Growth in the presence of the analogs did not select a population of higher resistance to the lethal effects of ultraviolet irradiation. The presence of a mixed dimer of thymine and 6-azathymine was not detected.