Probing and Oviposition Behavior of the Bayberry Whitefly (Homoptera: Aleyrodidae) on Young and Mature Lemon Leaves

Abstract

The probing and Oviposition behaviors of bayberry whitefly, Parabemisia myricae (Kuwana), on young and mature excised lemon leaves were studied. Discrimination among leaf ages took place on the leaf surface, not after phloem feeding. Ninety-two percent of contacts with the leaf surface resulted in a probe on young leaves compared with 31% on mature leaves (P < 0.0001). In contrast to long probes ≥2 min) observed on young leaves, none of the probes on mature leaves were greater than 40 s in duration and half the probes on mature leaves were terminated within 8 s of initiation. This suggests that mature leaves were rejected prior to penetration of the thick mature leaf cuticle. Seven pairs of previously undescribed sensoria were found at the apex of the whitefly's rostrum, and may play a role in host selection at the leaf surface. Oviposition occurred only on young leaves. Half the ovipositions took place within a minute of probe initiation, indicating that oviposition usually occurred before phloem feeding. When oviposition occurred during a probe, the probe was usually terminated shortly after oviposition (median = 5.5 s) and subsequent probes tended to be long (≥10 min).