Effects of host plant phenolic acids and nutrient status on oviposition and feeding of the cabbage white butterfly,Pieris rapae

Abstract

Abstract. Females of the cabbage white butterfly, Pieris rapae, lay eggs (oviposit) on plants in the Brassicaceae family (crucifers) that will serve as foodplants for their larvae. The presence of plant secondary metabolites (PSM), specifically glucosinolates in crucifers, serves as the primary cue for feeding and oviposition. However, the influence of other PSM, such as phenolic acids, has not been well characterized. Seedlings of Brassica rapa were treated with a phenolic acid (p-coumaric acid, ferulic acid, salicylic acid or protocatechuic acid) to see if they would deter or stimulate oviposition. Female butterflies were provided a choice of whether to lay eggs on control plants sprayed with deionized water or plants sprayed with a phenolic acid. Ferulic and p-coumaric acid, which are very similar in chemical structure, both had significant stimulatory effects on oviposition. The other two phenolic acids did not affect ovipositional choices. The effects of PSM may interact with other factors such as th...