STRATOSPHERIC OZONE DEPLETION AND PLANT-INSECT INTERACTIONS - EFFECTS OF UVB RADIATION ON FOLIAGE QUALITY OF CITRUS-JAMBHIRI FOR TRICHOPLUSIA NI

Projected decreases in stratospheric ozone may result in increases in shortwave ultraviolet (UVB) irradiation at the earth's surface. Furanocoumarins, phototoxic compounds found in Citrus jambhiri foliage, increase in concentration when these plants are grown under enhanced WB. Survivorship schedules of Trichoplusia ni (Lepidoptera: Noctuidae) caterpillars reared on plants in the presence and absence of enhanced UVB regimes differ significantly; larvae develop more slowly in early life when reared on plants exposed to increased UVB. This same developmental pattern is observed when T. ni larvae are reared on artificial diets amended with ecologically appropriate amounts of furanocoumarins. Thus, anthropogenically derived changes in stratospheric ozone and concomitant changes in W light quality at the earth's surface may influence ecological interactions between insects and their host plants by altering secondary metabolism and hence foliage quality for herbivores.