[Electron microscopic study of chicken fibroblasts infected with the Tyuleniy virus (author's transl)].

Uninfected and Tyuleniy virus-infected chick fibroblast cells were examined. Intracytoplasmic type A particles and immature type C particles of oncornavirus were found in uninfected cells. At 48 and 72 hours after inoculation of the cells with Tyuleniy virus a large number of mature C particles and virions of Tyuleniy virus were found in the cell cytoplasm.

Effects of Temperature on Photosynthesis and CO(2) Evolution in Light and Darkness by Green Leaves.

Using an open and a closed system of gas analysis, it was found that CO(2) evolution in light and in darkness from plant leaves (sunflower, soybean, watermelon, eggplant, and jackbean) have a different response to temperature. While the rate of CO(2) evolution in light increased with increasing temperature from 17 to 35 degrees and then declined, the rate of CO(2) evolution in darkness increased continuously up to 40 degrees . The rate of CO(2) evolution in light was affected by light intensity.

Determination of the Rate of CO(2) Evolution by Green Leaves in Light.

The rate of CO(2) evolution in light by green leaves was determined by 2 methods in a closed system of gas analysis and by measuring the amount of CO(2) evolved into a CO(2) free air stream in an open system. All methods gave similar results under comparable conditions.A light stimulated CO(2) evolution from green leaves was found in all the plant species studied except corn where there was no apparent CO(2) evolution in the light.

Seasonal Changes in the Distribution of Photo-assimilated C in Young Pine Plants.

Pinus strobus L. plants in their third year of growth were permitted to photoassimilate (14)CO(2) for about 1 hour at monthly intervals between April and October, and the subsequent distribution of (14)C in these plants was determined 8 hours, 1 month, 2 months or 4 months after photo-assimilation. In this way, the fate of (14)CO(2) photo-assimilated during different months of the growing season was observed.

Effects of Metabolic Inhibitors on the Rates of CO(2) Evolution in Light and in Darkness by Detached Spruce Twigs, Wheat, and Soybean Leaves.

Detached spruce twigs, wheat and soybean leaves were infiltrated with various metabolic inhibitors, placed in a closed system in CO(2)-free air and the amounts of CO(2) evolved in either light or darkness were determined with an infra-red CO(2) analyzer. In light, metabolic inhibitors always greatly suppressed evolution of CO(2), the magnitude of suppression varying between 50 to 80% of that without an inhibitor. This depressing effect became less pronounced with increasing oxygen.

Effect of Oxygen on Photosynthesis, Photorespiration and Respiration in Detached Leaves. II. Corn and other Monocotyledons.

The effect of O(2) on the CO(2) exchange of detached leaves of corn (Zea mays), wheat (Triticum vulgare), oats (Avena sativa), barley (Hordeum vulgare), timothy (Phleum pratense) and cat-tail (Typha angustifolia) was measured with a Clark oxygen electrode and infrared carbon dioxide analysers in both open and closed systems.Corn leaves did not produce CO(2) in the light at any O(2) concentration, as was shown by the zero CO(2) compensation point and the absence of a CO(2) burst in the first minute of darkness. The rate of photosynthesis was inhibited by O(2) and the inhibition was not completely reversible.

Effect of oxygen on photosynthesis, photorespiration and respiration in detached leaves. I. Soybean.

The effect of O(2) on the CO(2) exchange of detached soybean leaves was measured with a Clark oxygen electrode and infrared carbon dioxide analysers in both open and closed systems.The rate of apparent photosynthesis was inhibited by O(2) while the steady rate of respiration after a few minutes in the dark was not affected. Part of the inhibition of apparent photosynthesis was shown to be a result of increased photorespiration.