THE EFFECTS OF OZONE FUMIGATION ON THE PERFORMANCE OF THE BLACK BEAN APHID, APHIS-FABAE SCOP FEEDING ON BROAD BEANS, VICIA-FABA L

This paper presents the results of studies with ozone and Vicia faha/Aphis fabae and shows how a range of responses in aphid performance can occur depending on the exposure pattern and timing of ozone fumigations. The responses to acute (100 nl l-1) fumigations were complex. Increases in mean relative growth rate (MRGR) were observed with short fumigation times (< 24 h) and episodic fumigations (8 h day-1 for several days). Continuous fumigations in excess of 24 h however resulted in decreased MRGR of the aphids. Studies using artificial diet techniques showed that 100 nl l-1 ozone did not have a direct effect on the MRGR of A. fabae. Therefore the observed responses were due to changes in the host plant.