Aromatic Plant Odours of Anethum graveolens And Coriandrum sativum Repel Whitefly, Bemisia tabaci in Tomato

We studied the behavioural responses of female whitefly, Bemisia tabaci (Gennadius) towards headspace volatiles of tomato in the presence of aromatic intercrops, namely coriander (Coriandrum sativum L.) and dill (Anethum graveolens L.) using olfactometer bioassays, electrophysiological techniques and field experimentation. Olfactometer studies revealed the repellent nature of dill and coriander. Multiple-choice olfactometer studies revealed less residence time in tomato with coriander (T + Co; 1.33 ± 0.20 min) and tomato with dill (T + D; 1.97 ± 0.30 min) treated arms compared to sole tomato volatile treated arm (3.18 ± 0.35 min). Field studies also supported this trend, where significantly less whitefly incidence was recorded in treatment T + Co (2.34 ± 0.39 per three leaves) or T + D (3.33 ± 0.51 per three leaves) compared to sole tomato crop (5.71 ± 0.75 per three leaves). In coupled gas chromatography-electro­antennodetection (GC-EAD) studies, whitefly antenna responded to several compounds of dill and coriander. This study suggests that aromatic plants such as dill and coriander can be used as potential intercrop components in tomatoes to manage B. tabaci and the GC-EAD-identified compounds of dill and coriander will help formulate futuristic semiochemical-based pest management strategies against the whitefly.