Journal of Chemical Ecology

, Volume 35, Issue 5, pp 552–559

Neonate Silkworm (Bombyx mori) Larvae Are Attracted to Mulberry (Morus alba) Leaves with Conspecific Feeding Damage

  • Allison C. Mooney
  • Hugh M. Robertson
  • Kevin W. Wanner
Article

DOI: 10.1007/s10886-009-9639-z

Cite this article as:
Mooney, A.C., Robertson, H.M. & Wanner, K.W. J Chem Ecol (2009) 35: 552. doi:10.1007/s10886-009-9639-z

Abstract

The silkworm Bombyx mori is a molecular genetic model for the Lepidoptera. Its odorant receptor genes have been described, and preliminary studies suggest that several are expressed specifically in the larval caterpillar stage. This study was undertaken to identify olfactory behaviors specific to the larvae. A two-choice leaf disk bioassay with naive neonate larvae was used to evaluate the attractiveness of three types of mulberry leaf (Morus alba): newly flushed leaves from branch tips, mature leaves, and mature leaves with feeding damage caused by conspecific larvae. Mature leaves with feeding damage were the most attractive, newly flushed leaves were moderately favored, and undamaged mature leaves were the least attractive. Volatile odors collected from whole mulberry leaves by using solid-phase microextraction fibers were analyzed by gas chromatography-mass spectrometry. The volatile profile of newly flushed leaves and mature leaves damaged by conspecific larvae was more complex compared to undamaged mature leaves. By comparing the volatile makeup of each leaf type, a list of 22 candidate odors responsible for attracting the neonate larvae was generated; α-farnesene was particularly notable as a herbivore-induced volatile. These odors will be used in future in vitro studies to determine whether they activate larval-specific odorant receptors.

Keywords

Silkworm Bombyx mori Mulberry Leaf volatiles Larval olfaction 

Supplementary material

10886_2009_9639_Fig3_ESM.gif (10 kb)
Supplementary Fig. 1

Volatile profile of filter paper exposed to mature mulberry leaves that were fed upon for 24 h by neonate silkworm larvae. One major peak (peak #C) representing α-farnesene was detected. Two minor peaks were identified as 6-methyl-5-hepten-2-one (peak A) and (Z)-3-hexenyl 2-methylbutanoate (peak B). Retention time (min) is labeled on the x-axis, relative abundance (×106) on the y-axis. (GIF 9 kb)

10886_2009_9639_Fig3_ESM.eps (1.2 mb)
High resolution image (EPS 1192 kb)

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Allison C. Mooney
    • 1
  • Hugh M. Robertson
    • 1
  • Kevin W. Wanner
    • 1
    • 2
  1. 1.Department of EntomologyUniversity of Illinois at Urbana-ChampaignUrbanaUSA
  2. 2.Entomology, Department of Plant Sciences and Plant PathologyMontana State UniversityBozemanUSA