Quantitative and temporal analysis of effects of twospotted spider mite (acari: Tetranychidae) female sex pheromone on male guarding behavior.

Responses of male twospotted spider mite,Tetranychus urticae (Koch), to female sex pheromone were described by a glass slide bioassay and computerized pathway digitizer. Pheromone was extracted from quiescent deutonymphs and fractionated by HPLC, and responses of guarding males to each fraction, all fractions combined, unfractionated extract, and a hexane control were bioassayed for 6 min. Mean angular velocities, linear velocities, percent time stationary, and distance from the 3-mm-diameter treatment circle were calculated for each mite at 20-sec intervals and these behavioral parameters regressed on time.

Induction of Glutamine Synthetase Activity in Nonnodulated Roots of Glycine max, Phaseolus vulgaris, and Pisum sativum.

Nitrate or ammonium fertilization significantly increased glutamine synthetase (GS) activity in nonnodulated roots of French bean (Phaseolus vulgaris), soybean (Glycine max), and pea (Pisum sativum). Western analysis revealed substantial GS antibody-positive protein in root extracts that had minimal GS activity, indicating that an inactive form of GS may be present in nonfertilized plants.

Arrestment of male twospotted spider mite caused by female sex pheromone.

A glass slide bioassay was used to evaluate male twospotted spider mite,Tetranychus urticae Koch, arrestment caused by quiescent deutonymph extract. Males that were guarding quiescent deutonymphs prior to being tested were arrested by a 3-mm-diameter circle of quiescent deutonymph extract; nonguarding males and adult females were not arrested. Extracts of allT.

Asparagine biosynthesis in soybean nodules.

Asparagine biosynthesis in soybean (Glycine max [L.] Merr.) nodules has been difficult to demonstrate due to the poor conversion of suspected immediate precursors to asparagine and the instability of the key enzyme asparagine synthetase.