Effects of current velocity, irradiance, and grazing on the
biomass, taxonomic structure, physiognomy, and chemical composition
of lotic algal assemblages were investigated. Four experiments,
lasting 32 to 75 days, were conducted in laboratory streams to
determine how these factors affect algal assemblages singly, and in
concert with each other.
Regardless...
Over the last decade a new perspective on how forest ecosystems operate has emerged. Ecosystems appear much more flexible than we once thought. Even the most persistent is still evolving in composition. Yet for all their diversity, very similar processes are seen as operating in all forests, providing a point...
Small amounts of carbon from glucose and leucine added at natural
concentrations to seawater were biologically transformed to higher
molecular weight (MW) dissolved materials which persisted through six
months of incubation. These materials were resistant to biological
utilization: only 1 to 17% of the higher MW carbon was respired when...
The lentil strain of pea seedborne mosaic virus, PSbMV-L, was
distinguished from the standard isolates of PSbMV by a natural inoculum
reservoir in lentil seed and by separate resistance genes in Pisum
and Lens. PSbMV-L was intermediate in symptom severity between the
standard and New Zealand isolates of PSbMV.
Seed...
The lentil strain of pea seedborne mosaic virus, PSbMV-L, was
distinguished from the standard isolates of PSbMV by a natural inoculum
reservoir in lentil seed and by separate resistance genes in Pisum
and Lens. PSbMV-L was intermediate in symptom severity between the
standard and New Zealand isolates of PSbMV.
Seed...
Factors influencing pesticide susceptibility and
resistance were studied in Psylla pyricola Foerster, and
its mirid predator, Deraeocoris brevis Knight in the
Rogue River Valley, Oregon. Factors studied were at the
biochemical, life history, and population ecology
levels.
Studies on detoxification enzymes showed that
glutathione S-transferase and cytochrome P-450
monooxygenase activities...