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The mode of action for radiation is that cells with a high mitotic rate are more radiosensitive; therefore,
mitotically active reproductive cells are the most susceptible to killing and sterilization when exposed
to ionizing radiation (Bakri et al. 2005). Research showed that adult hemipterans generally began to
become sterile, at least partially, after exposure to 30 to 60100 Grays (Gy) of ionizing radiation (Mau
et al. 1967, LaChance et al. 1970, LaChance and Riemann 1973). For example, Nezara viridula adult
females that were irradiated with low level (<10 Gy) radiation as fourth instars produced large numbers
of nonviable eggs and exhibited significantly lower fecundity than non-irradiated females (Dyby and
Sailer 1999). Additional stresses, including diet and inbreeding, resulted in further declines in fecundity
and fertility in the test population. When exposed to higher levels of radiation (20 Gy), only half of the
individuals survived to the adult stage.
A frequent concern is that foods or insects exposed to radiation for quarantine or pest management
may become radioactive. However, the quantum energies of acceptable radioactive sources for these
purposes are insufficient to induce radioactivity (Bakri et al. 2005).
16.3.1.3.1.3 Sterile-Insect Technique The sterile insect technique is a pest management strategy
whereby an overwhelming number of sterile individuals (often males) are released into the environment
to mate with wild individuals resulting in non-fertile offspring. The sterile insect technique is widely
acclaimed for its role in the success of the area-wide integrated pest management program that eradi-
cated Cochliomyia hominivorax from the southern United States (Knipling 1955, 1960). Unfortunately,
the specific factors that made the C. hominivorax program successful are not present with other pests,
such as stink bugs. For example, C. hominivorax individuals are easy to rear in large numbers, they
mate only once in their lifetime, and adult males do not inflict economic injury. By comparison, it
costs a minimum of several dollars per insect to rear stink bugs [e.g., the brown stink bug, Euschistus
servus (Say); the brown marmorated stink bug, Halyomorpha halys (Stål); and the southern green stink
bug, Nezara viridula) to adults (Michael D. Toews, personal observation). Rearing enough stink bugs to
release thousands per hectare in an area-wide program would be cost prohibitive, not to mention that the
sterilized adults would feed and inflict serious economic injury. Further, stink bugs mate multiple times
thereby increasing the likelihood of mating with a feral (non-sterile) individual at some point.
16.3.1.3.2 Mating Disruption
Mating disruption is a pest management technique whereby large amounts of synthetic sex pheromone
are released into the environment to interfere with the ability of males and females to find each other
and mate. Unmated females fail to produce viable eggs, and pest populations quickly decline. Shorey
et al. (1967) used mating disruption to control Trichoplusia ni (Hübner). Subsequent investigations and
commercial applications have included disruption of agricultural and forest insect pests, generally moths
(Cardé and Minks 1995). This technique has shown tremendous utility for reducing Plodia interpunctella
Hübner populations in confined environments such as storage warehouses and food- and feed-processing
mills (Trematerra et al. 2011). Mahroof and Phillips (2014) documented immediate trap shutdown and
a significant long-term reduction of a beetle, Lasioderma serricorne (F.), in food- and feed-processing
facilities. Mating disruption has not been studied for hemipterans with the exception of mealybug and
scale insects (Walton et al. 2006, Vacas et al. 2011). Pheromone-based mating disruption has been sug-
gested for Euschistus servus (Borges et al. 2001), but not tested empirically.
16.3.1.4 Regulatory (Legal) Control
Regulatory or legal control of insects can be defined as the approach to control insects with laws that
mandate procedures, such as inspection, certification, quarantine, and eradication, to prevent or mitigate
problems with offending species.
16.3.1.4.1 Quarantine
The economic impact of invasive species is an estimated $120 billion annually in losses in the United
States, which includes $14.4 billion for arthropod crop pests and $2.1 billion for arthropod forest pests