A mixture of gases roughly simulating the primitive terrestrial atmosphere has been subjected to shock heating followed by a rapid thermal quench. Under strictly homogeneous conditions there is a very high efficiency of 5 x 10(10) molecules per erg of shock-injected energy for production of alpha-amino acids. Calculations suggest that rapid quenching bypasses the usual thermochemical barrier. The product of energy flux and efficiency implies the unexpected conclusion that shocks occurring on atmospheric entry of cometary meteors and micrometeorites and from thunder may have been the principal energy sources for pre-biological organic synthesis on the primitive earth.

Broomrape manipulates the host by acting as a sink for auxin. Disruption of auxin action or auxin flow at the contact site could be a novel basis for controlling infection by Orobanche.

The effect of a beta-1,3-glucanase (Glucanex) on cultures of Botrytis cinerea was examined. The enzyme released reducing sugars from the mycelium and from the glucan secreted into the culture medium. The morphology of the mycelium was changed in the presence of Glucanex. The measured activity of guaiacol peroxidase, laccase, and catalase was increased when the mycelium was treated with Glucanex. Culture of the mycelium in the presence of Glucanex resulted in an increase in catalase activity. We suggest that the glucan plays a role in protecting the fungus from host response and may assist in the initial stages of host infection.

No abstract