Biology Reference
In-Depth Information
Table 14.1: (Continued)
Table 14.1: Selected Examples of Genetic Modifications of Arthropods Using Multiple Methods.
Project goals
Selected reference(s)
Wolbachia
shortens life and affects feeding of
Ae. aegypti
McMenniman et al. 2009, Moreira
et al. 2009b
Zinc-finger nucleases for genome modification
Silk moth modification
Takasu et al. 2010
Zinc-finger nucleases modify
G. bimaculatus
genes
Watanabe et al. 2012
movement of the transgenes by the
piggyBac
vector), lines that had the ability to
develop without diapause (to screen the putative transformant lines), or the abil-
ity to diapause (to be able to store eggs over time for future use). Because silk
moths cannot survive in the wild on their own, transgenic silk moths that escape
from mass-rearing facilities are unlikely to establish in the environment.
Natural enemies of pest insects and mites have been modified by traditional
breeding methods and by hybridization of different strains to achieve hybrid
vigor (
Hoy 1976, 1990a,b, 2003,
Stouthamer et al. 1992, Heilmann et al. 1994,
Whitten and Hoy 1999
). A pesticide-resistant predatory mite, developed by tra-
ditional breeding methods, was deployed in an integrated mite management
program in almonds in California and provided proof-of-principle that geneti-
cally modified natural enemies could be incorporated into practical pest-man-
agement programs (
Hoy 1985
). The predators provided effective control of
spider mites, reduced the need for costly pesticides, reduced crop-production
costs, saving almond growers
≈
US$22 million per year due to fewer applications
of pesticides to control the spider mites (
Headley and Hoy 1987
).
Genetic improvement of natural enemies for biological control of pest insects
and mites by traditional genetic methods has involved selecting for resistance to
pesticides, lack of diapause, and increased tolerance to temperature extremes,
although modification of other traits, such as dispersal rate and sex ratio, theo-
retically could result in improved biological control. Future projects could result
in genetically modified natural enemies with improved traits, especially now
that the genomes of several natural enemy species have been (or are being)
sequenced and genes and their regulatory elements are being identified.
14.3.2 Pest Insects
During the past 40 years, irradiation or chemicals have been used to sterilize a
number of pest insects for use in genetic-control programs (
Wright and Pal 1967,
Pal and Whitten 1974, Curtis 1979, LaChance 1979
,
Whitten 1979
,
Tan 2000
).
