The effect of ozone, nitrogen dioxide or nitric oxide fumigation of cereals on the rose grain aphid Metopolophium dirhodum

The performance of the rose grain aphid ( Metopolophium dirhodum) on cereals, polluted for different short durations, with either ozone or nitrogen oxides, was investigated using a small chamber fumigation system. The parameter used to measure aphid performance was the mean relative growth rate (MRGR) which was calculated following fumigation of the plant only. The intrinsic rate of natural increase ( r m) was calculated where a significant difference in MRGR was found. No general aphid response was found for any pollutant following different fumigation durations, although significant increases in performance following certain fumigation regimes were observed. The direct effect of the pollutant gases on the aphid was investigated using artificial diets and was found to be unimportant.