Identification and population dynamics of bacteria in symptomatic oat leaves.

Bacteria isolated from symptomatic oat leaves included pseudomonads,Erwinia herbicola, and others.Pseudomonas coronafaciens was isolated predominantly from leaves with halo blight symptoms or necrotic spots. Leaves with red leaf symptoms yielded many types of bacteria, including saprophytic pseudomonads,P.

Technique for measuring laser beam propagation direction fluctuations.

A technique has been developed for the measurement of a component of the position of a small target within a laser beam and used to measure atmospherically induced beam-pointing fluctuations. A modulation is impressed on the beam in a manner such that the modulation phase varies with position across the beam, so the relative modulation phase of the signal returned from a remote retroreflector is indicative of the position of the retroreflector within the beam. The far-field modulation phase distribution is shown to be relatively unaffected by turbulence, and results are given for a series of experimental measurements of beam-pointing fluctuations.