Contents - Faperta

Molecular Markers for Diagnosis of Insect Pests and Their Natural Enemies 483
allowed analysis of spatial distribution of geographical lineages in the case of braconid
parasitoids (Hufbauer, Bogdanowicz, and Harrison, 2004), honeybees (De la Rua et al., 2001),
bumblebees (Widmer et al., 1998), and yucca moth, Prodoxus quinquepunctella (Chambers)
(Althoff and Thomson, 2001). RAPDs have been used for studies on asexual insects such as
aphids (Lushai et al., 1997), and the parasitoids, A. ervi (Daza-Bustamante et al., 2002) and
D. rapae (Vaughn and Antolin, 1998).
Application of Molecular Markers for Studying Social
Behavior of Insects
Molecular techniques have been used to study behavioral aspects of insect populations
(Hughes, 1997). Application of molecular techniques has suggested that behavioral dynamics
of insect populations is much more complex than had been known previously. Use of
molecular techniques has allowed a better understanding of kinship, colony sex status, and
cooperative breeding. Molecular analysis of insect behavior will lead to an understanding
of how changes in species environment have been associated with evolutionary changes in
social behavior. Molecular markers have also been used to study the behavior of insects in
relation to their hosts/environment. Mitochondrial DNA has been used to detect an alien
inseminated female in the nest of the polygynous ant, Leptothorax acervorum F. (Stille and
Stille, 1992). Synthetic probes have been used in studies on benefi cial Hymenoptera for
studying colony structure and mating behavior, for example, paper wasp, Polistes annularis
(L.) (Queller et al., 1997). Microsatellite markers have been used to genotype wingless
colony queen and sperms in the spermatheca (Hammond, Bourke, and Bruford, 2001) to
understand colony structure and mating preference. The results showed that 95% of the
females mated only once, while the female offspring attributable to 31 queens were full sisters,
and that L. acervorum adults mate at random. Using microsatellite markers, Keller and
Fournier (2002) suggested that kin recognition mediated by genetic cues in the Argentine ant,
Linepithema humile (Mayr) may be intrinsically error prone within colonies of social insects.
Molecular Basis of Insect–Plant Interactions
Functional genomics can also be used to study the interaction of insects with their host
plants. Nicotiana attenuata Torrey ex Watson genes that respond to feeding by Manduca
sexta L. have been identifi ed through differential display PCR, and then spotted onto
microarray (Halitschke et al., 2003; Hui et al., 2003). These have been used to identify
genes that responded to wounding as opposed to insect secretions, as well as to different
components in insect secretions. Over half of the plant genes that were induced by M.
sexta secretions could also be induced by fatty acid–amino acid conjugates in the regurgitant,
suggesting that plants recognize the herbivores through the composition of their
oral secretions (Halitschke et al., 2003). Microarrays have also been used to understand
the response of cowpea weevil, Callosobruchus maculatus (F.), to defenses produced by
cowpea (Moon et al., 2004). Of the 1,920 cDNAs on the array, I51 were induced or suppressed
by soyacystatin N (protease inhibitor). Proteases, carbohydrate digestive enzymes,