Phloem-specific resistance in Brassica oleracea against the whitefly Aleyrodes proletella

作者：Broekgaarden Colette^*; Riviere Pierre; Steenhuis Greet; Cuenca Maria del Sol; Kos Martine; Vosman Ben

来源：Entomologia Experimentalis et Applicata, 2012, 142(2): 153-164.

DOI：10.1111/j.1570-7458.2011.01210.x

• cabbage
• insect performance
• insect preference
• EPG recording
• insect abundance
• age-dependent resistance
• phloem-based antibiosis
• Y-tube olfactometer
• Hemiptera
• Aleyrodidae

The cabbage whitefly [Aleyrodes proletella L. (Hemiptera: Aleyrodidae)] is becoming a serious pest in Brassica oleracea L. (Brassicaceae) crops. However, almost nothing is known about the interaction of this insect with its host plants. Previous studies have shown differences in the natural occurrence of adults, eggs, and nymphs on the closely related B. oleracea cultivars Christmas Drumhead and Riviera grown in the field. In this study, we aimed to identify the nature of these differences and to gain insight into the resistance mechanisms against A. proletella. We used no-choice experiments on field- and greenhouse-grown plants to show that the differences between the two cultivars are mainly based on antibiosis (traits that reduce herbivore performance) and not on antixenosis (traits that deter herbivory). This was further supported by laboratory choice experiments that indicated little or no discrimination between the two cultivars based on plant volatiles. We showed that resistance is dependent on plant age, that is, resistance increased during plant development, and is mainly independent of environmental factors. Analysis of probing behaviour revealed that the resistance trait affects A. proletella at the phloem level and that morphological differences between the two cultivars are most likely not involved. We suggest that compounds present in the phloem reduce sap ingestion by the whitefly and that this explains the observed resistance.

• 出版日期2012-2