Terrain and laboratory research were conducted to determine the potential of Gastroidea viridula Deg. (Coleoptera: Chrysomelidae) to control mossy sorrel (Rumex confertus Willd.). In a field study, the dynamicof plant biomass and number of larvae occurring on that plant were investigated. The Pearson’s linear correlation coefficient of biomass increase in time equalled, to r = 0.96. The regression equation showed, that the plant daily growth reached 29 g; and 210 g per week, consequently. In the laboratory, weight of consumed food by larvae, and larval body weight were measured at 20°C. First generation of G. viridula was taken into consideration. Total weight of consumed leaves by all three instars of a single larva, during 50 days of the development amounted to 1.243 g. Also seasonal abundance of larvae was observed. On May 25th the highest observed number of G. viridula larvae per plant ranged from 435 to 469 individuals. This species may be of usefulness in biological control of mossy sorrel.

Plants under attack of herbivores can emit increased amounts of volatile compounds from their leaves. Similarly, mechanically-injured plants can emit volatile chemicals that differ both quantitatively and qualitatively from undamaged plants. In this experiment, mechanical injury increased the release of the secondary metabolites linalool (3,7-dimethyl-1,6-octadien-3-ol) and linalool oxide (5-ethenyltetrahydro-2-furanmethanol) by wheat plants. The amounts released varied significantly with injury type and the period of time after injury. The time interval for the volatile collection within the photophase also influenced the amount collected for each day. The increased emission of these compounds, as a result of injury, may be explained as a defense mechanism against wounding. The role of these plant volatiles can be further investigated in the context of plant response to mechanical injury, within the broader context of all types of injury.