Effect of water stress and aphid herbivory on flavonoids in broccoli (Brassica oleracea var. italica Plenck).
The aim of this study was to determine changes within flavonoid levels in broccoli plants (Brassica oleracea var. italica Plenck) induced by water stress conditions and aphid hervivory. Three water treatments, well-watered, drought, and water-logged, were applied to plants. Two aphid species, the specialist Brevicoryne brassicae (L.) and the generalist Myzus persicae (Sulzer), were used to evaluate combination effects under water stress. Drought and water-logged stress decreased plants water content and reduced the growth of broccoli. Analysis of flavonoids revealed that the broccoli variety ‚Calabrese‘ only contained kaempferol. The kaempferol content was similar in all experimental plants after one week cultivation under various water treatments. However, after two weeks of water stress, significantly higher kaempferol amounts were detected in drought and water-logged broccoli plants compared to well-watered plants. Herbivory of the aphids‘ B. brassicae and M. persicae did not change the level of kaempferol in broccoli, regardless of the water treatment.
Khan, M.A.M.; Ulrichs, C.; Mewis, I. 2011. Effect of water stress and aphid herbivory on flavonoids in broccoli (Brassica oleracea var. italica Plenck). Journal of Applied Botany and Food Quality-Angewandte Botanik 84, 178-182.