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In its defense against herbivores, cotton (Gossypium sp.) relies in part on the production of a set of inducible, non-volatile terpenoids. Under uniform damage levels, in planta allocation of induced cotton terpenoids has been found to be highest in youngest leaves, supporting assumptions of the optimal defense theory (ODT) which predicts that plants allocate defense compounds to tissues depending on their value and the likelihood of herbivore attack. However, our knowledge is limited on how varying, and thus more realistic, damage levels might affect cotton defense organization. We hypothesized that the allocation of terpenoids and densities of terpenoid-storing glands in leaves aligns with assumptions of the ODT, even when plants are subjected to temporally, spatially and quantitatively varying caterpillar (Heliothis virescens) damage. As expected, cotton plants allocated most of their defenses to their youngest leaves regardless of damage location. However, defense induction in older leaves varied with damage location. For at least 14 days after damage treatments ended, plants reallocated defense resources from previously young leaves to newly developed leaves. Furthermore, we observed a positive hyperbolic relationship between leaf damage area and both terpenoid concentrations and gland densities, indicating that cotton plants can fine-tune defense allocation. Although it appears that factors like vascular constraints and chemical properties of individual defense compounds can affect defense levels, our results overall demonstrate that induced defense organization of cotton subjected to varying damage treatments is in alignment with key assumptions of the ODT. [ABSTRACT FROM AUTHOR]

Laboratory studies were conducted to investigate tritrophic transfer of insecticidal Cry proteins from transgenic cotton to an herbivore and its predator, and to examine effects of these proteins on the predator's development, survival, and reproduction. Cry1Ac and Cry2Ab proteins from the bacterium Bacillus thuringiensis (Bt) produced in Bollgard-II (BG-II, Event 15985) cotton plants were acquired by Thrips tabaci Lindeman (Thysanoptera: Thripidae), an important sucking pest of cotton, and its generalist predator, Orius insidiosus (Say) (Hemiptera: Anthocoridae). The average protein titers in BG-II cotton leaves were 1,256 and 43,637 ng Cry1Ac and Cry2Ab per gram fresh leaf tissue, respectively. At the second trophic level, larvae of T. tabaci reared on BG-II cotton for 48-96 h had 22.1 and 2.1% of the Cry1Ac and Cry2Ab levels expressed in leaves, respectively. At the third trophic level, O. insidiosus that fed on T. tabaci larvae had 4.4 and 0.3% of the Cry1Ac and Cry2Ab protein levels, respectively, expressed in BG-II plants. O. insidiosus survivorship, time of nymphal development, adult weight, preoviposition and postoviposition periods, fecundity, and adult longevity were not adversely affected owing to consumption of T. tabaci larvae that had fed on BG-II cotton compared with non-Bt cotton. Our results indicate that O. insidiosus, a common predator of T. tabaci, is not harmed by BG-II cotton when exposed to Bt proteins through its prey. Thus, O. insidiosus can continue to provide important biological control services in the cotton ecosystem when BG-II cotton is used to control primary lepidopteran pests. [ABSTRACT FROM AUTHOR]

Variation in plant quality and natural enemy abundance plays an important role in insect population dynamics. In manipulative field studies, we evaluated the impact of varying irrigation levels and insecticide type on densities of Lygus hesperus Knight and the arthropod predator community in cotton. Three watering levels were established via irrigations timed according to three levels of percent soil water depletion (SWD): 20, 40, or 60, where 40% SWD is considered standard grower practice, 60% represents a deficit condition likely to impose plant productivity losses, and 20% represents surplus conditions with likely consequences on excessive vegetative plant production. The two key L. hesperus insecticides used were the broad-spectrum insecticide acephate and the selective insecticide flonicamid, along with an untreated check. We hypothesized that densities of L. hesperus and its associated predators would be elevated at higher irrigation levels and that insecticides would differentially impact L. hesperus and predator dynamics depending on their selectivity. L. hesperus were more abundant at the higher irrigation level (20% SWD) but the predator densities were unaffected by irrigation levels. Both L. hesperus and its predators were affected by the selectivity of the insecticide with highest L. hesperus densities and lowest predator abundance where the broad spectrum insecticide (acephate) was used. There were no direct interactions between irrigation level and insecticides, indicating that insecticide effects on L. hesperus and its predators were not influenced by the irrigation levels used here. The implications of these findings on the overall ecology of insect-plant dynamics and yield in cotton are discussed. [ABSTRACT FROM AUTHOR]

Geocoris punctipes (Say) and Orius insidiosus (Say) are generalist predators found in a wide range of crops, including cotton (Gossypium hirsutum L.) and maize (Zea mays L.), where they provide important biological control services by feeding on an array of pests, including eggs and small larvae of caterpillars. A high percentage of cotton and maize in the United States and several other countries are transgenic cultivars that produce one or more of the insecticidal Cry proteins of Bacillus thuringiensis Berliner (Bt). Here we quantify effects of three Cry proteins on the life history of these predators over two generations when they are exposed to these Cry proteins indirectly through their prey. To eliminate the confounding prey quality effects that can be introduced by Bt-susceptible prey, we used Cry1Ac/Cry2Ab-resistant Trichoplusia ni (Hübner) and Cry1 F-resistant Spodoptera frugiperda (J. E. Smith) in a series of tri-trophic studies. Survival, development, adult mass, fecundity, and fertility were similar when predators consumed larvae feeding on Cry1Ac/Cry2Ab cotton or Cry1 F maize compared with prey feeding on isogenic or near-isogenic cotton or maize. Repeated exposure of the same initial cohort over a second generation also resulted in no differences in life-history traits when feeding on non-Bt- or Bt-fed prey. Enzyme-linked immunosorbent assay showed that predators were exposed to Bt Cry proteins from their prey and that these proteins became increasingly diluted as they moved up the food chain. Results show a clear lack of effect of three common and widespread Cry proteins on these two important predator species. The use of resistant insects to eliminate prey quality effects provides a robust and meaningful assessment of exposure and hazard. [ABSTRACT FROM AUTHOR]

Highlights: [•] Biological control plays an important role for control of cotton pests in China. [•] More than a hundred species of major arthropod predators and parasitoids of cotton insect pests have been described. [•] Trichogramma spp., Bacillus thuringiensis and HaNPV etc. have been mass reared or commercially produced and used. [•] Biological control strategies have been developed for control of non-target insect pests in Bt cotton fields. [ABSTRACT FROM AUTHOR]

The abundance and distribution of insect herbivores is determined by, among other things, plant quality and natural enemies. These two factors vary temporally and spatially, subsequently affecting seasonal population dynamics. The relative influence of plant quality and natural enemies on the seasonal dynamics ofBemisia tabaci (Gennadius) was investigated in a 3-yr field study in cotton. Plant quality was manipulated through varying irrigation regimes: irrigations done at 20, 40, and 60% soil water depletions; and natural enemy densities were manipulated using broad spectrum insecticide applications that reduced their densities compared with unswayed controls. In each year, densities of B. tabaci eggs, large nymphs and adults were consistently higher when natural enemy densities were reduced compared with when they were left unaltered, regardless of irrigation regime. In contrast, effects of plant quality on densities of all whitefly stages were weak and inconsistent. In addition, natural enemy densities and predator:prey ratios also were not generally affected by plant quality. Interactions between natural enemies mad plant quality on whitefly dynamics were rare. In general, whitefly densities were elevated two-thirds of the time and increased two- to sixfold when natural enemy densities were reduced compared with plant quality effects which influenced whitefly densities about one-third of the time and were expressed inconsistently over the years. This indicates that natural enemies exert a comparatively greater influence on seasonal dynamics of B. tabaci in cotton than plant quality, as manipulated by differential irrigation. [ABSTRACT FROM AUTHOR]

The biological control function provided by natural enemies is regarded as a protection goal that should not be harmed by the application of any new pest management tool. Plants producing Cry proteins from the bacterium, Bacillus thuringiensis (Bt), have become a major tactic for controlling pest Lepidoptera on cotton and maize and risk assessment studies are needed to ensure they do not harm important natural enemies. However, using Cry protein susceptible hosts as prey often compromises such studies. To avoid this problem we utilized pest Lepidoptera, cabbage looper (Trichoplusia ni) and fall armyworm (Spodoptera frugiperda), that were resistant to Cry1Ac produced in Bt broccoli (T. ni), Cry1Ac/Cry2Ab produced in Bt cotton (T. ni), and Cry1F produced in Bt maize (S. frugiperda). Larvae of these species were fed Bt plants or non-Bt plants and then exposed to predaceous larvae of the green lacewing Chrysoperla rufilabris. Fitness parameters (larval survival, development time, fecundity and egg hatch) of C. rufilabris were assessed over two generations. There were no differences in any of the fitness parameters regardless if C. rufilabris consumed prey (T. ni or S. frugiperda) that had consumed Bt or non-Bt plants. Additional studies confirmed that the prey contained bioactive Cry proteins when they were consumed by the predator. These studies confirm that Cry1Ac, Cry2Ab and Cry1F do not pose a hazard to the important predator C. rufilabris. This study also demonstrates the power of using resistant hosts when assessing the risk of genetically modified plants on non-target organisms. [ABSTRACT FROM AUTHOR]

Background: Many polyphagous pests sequentially use crops and uncultivated habitats in landscapes dominated by annual crops. As these habitats may contribute in increasing or decreasing pest density in fields of a specific crop, understanding the scale and temporal variability of source and sink effects is critical for managing landscapes to enhance pest control. Methodology/Principal Findings: We evaluated how local and landscape characteristics affect population density of the western tarnished plant bug, Lygus hesperus (Knight), in cotton fields of the San Joaquin Valley in California. During two periods covering the main window of cotton vulnerability to Lygus attack over three years, we examined the associations between abundance of six common Lygus crops, uncultivated habitats and Lygus population density in these cotton fields. We also investigated impacts of insecticide applications in cotton fields and cotton flowering date. Consistent associations observed across periods and years involved abundances of cotton and uncultivated habitats that were negatively associated with Lygus density, and abundance of seed alfalfa and cotton flowering date that were positively associated with Lygus density. Safflower and forage alfalfa had variable effects, possibly reflecting among-year variation in crop management practices, and tomato, sugar beet and insecticide applications were rarely associated with Lygus density. Using data from the first two years, a multiple regression model including the four consistent factors successfully predicted Lygus density across cotton fields in the last year of the study. Conclusions/Significance: Our results show that the approach developed here is appropriate to characterize and test the source and sink effects of various habitats on pest dynamics and improve the design of landscape-level pest management strategies. [ABSTRACT FROM AUTHOR]

Abstract: Integrated control systems are based on the complimentary contribution of chemical and biological control fostered by conservation of natural enemies. Yet, in the 50years since the integrated control concept [ICC] [Stern, V.M., Smith, R.F., van den Bosch, R., Hagen, K.S., 1959. The integrated control concept. Hilgardia 29, 81–101] was introduced there are few operational programs and even fewer attempts to analyze the mechanisms that allow chemical and biological control to act in concert. The dearth of demonstrable evidence for the ICC has eroded the credibility of biological control and its usage in operational IPM plans. We used in situ life tables within an experimental design to measure and compare the contribution and interaction of biological control and insecticides as tactical components within three pest management systems for Bemisia tabaci (Gennadius) in cotton. Insecticides were the key factor immediately following applications of broad-spectrum materials or one of two selective insect growth regulators (IGRs), and this mortality replaced that provided by natural enemies. Two to six weeks later, however, mortality from natural enemies, primarily predation, in the IGR regimes rebounded to the high levels observed in untreated controls and became the key factor. Mortality from natural enemies remained depressed in the broad-spectrum insecticide regime. Single IGR applications were sufficient to suppress B. tabaci populations throughout the season, while up to five broad-spectrum applications were needed to achieve comparable control. The chemical residual of IGRs was limited to several weeks, demonstrating a key role for mortality from conserved natural enemies that extended the control interval. This “bioresidual” allows for long-term, commercially-acceptable pest suppression following the use of selective insecticides. We provide a rare experimental illustration of integrated control, where chemical and biological controls “augment one another”. Our approach and methodology could be applied to demonstrate and validate integrated control in many other systems, addressing a critical need for implementation of biological control in practicing IPM systems. [Copyright &y& Elsevier]

The article discusses the significance of integrated pest management (IPM) in the cotton industry in Arizona. It says that the adaptation of farmers on IPM helped them to reduce the use of harmful insecticides and helped to increase their crop production. It also mentions that IPM gave farmers the knowledge on the appropriate method for pest control including the selection of insecticides and the strategy in understanding biological control.

Abstract: Data on seasonal population abundance of Bemisia tabaci biotype B (silverleaf whitefly (SLW)) in Australian cotton fields collected over four consecutive growing seasons (2002/2003–2005/2006) were used to develop and validate a multiple-threshold-based management and sampling plan. Non-linear growth trajectories estimated from the field sampling data were used as benchmarks to classify adult SLW field populations into six density-based management zones with associated control recommendations in the context of peak flowering and open boll crop growth stages. Control options based on application of insect growth regulators (IGRs) are recommended for high-density populations (>2 adults/leaf) whereas conventional (non-IGR) products are recommended for the control of low to moderate population densities. A computerised re-sampling program was used to develop and test a binomial sampling plan. Binomial models with thresholds of T=1, 2 and 3 adults/leaf were tested using the field abundance data. A binomial plan based on a tally threshold of T=2 adults/leaf and a minimum sample of 20 leaves at nodes 3, 4 or 5 below the terminal is recommended as the most parsimonious and practical sampling protocol for Australian cotton fields. A decision support guide with management zone boundaries expressed as binomial counts and control options appropriate for various SLW density situations is presented. Appropriate use of chemical insecticides and tactics for successful field control of whiteflies are discussed. [Copyright &y& Elsevier]

Background: Uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal Cry proteins of Bacillus thuringiensis (Bt). We performed meta-analyses on a modified public database to synthesize current knowledge about the effects of Bt cotton, maize and potato on the abundance and interactions of arthropod non-target functional guilds. Methodology/Principal Findings: We compared the abundance of predators, parasitoids, omnivores, detritivores and herbivores under scenarios in which neither, only the non-Bt crops, or both Bt and non-Bt crops received insecticide treatments. Predators were less abundant in Bt cotton compared to unsprayed non-Bt controls. As expected, fewer specialist parasitoids of the target pest occurred in Bt maize fields compared to unsprayed non-Bt controls, but no significant reduction was detected for other parasitoids. Numbers of predators and herbivores were higher in Bt crops compared to sprayed non-Bt controls, and type of insecticide influenced the magnitude of the difference. Omnivores and detritivores were more abundant in insecticide-treated controls and for the latter guild this was associated with reductions of their predators in sprayed non-Bt maize. No differences in abundance were found when both Bt and non-Bt crops were sprayed. Predator-to-prey ratios were unchanged by either Bt crops or the use of insecticides; ratios were higher in Bt maize relative to the sprayed non-Bt control. Conclusions/Significance: Overall, we find no uniform effects of Bt cotton, maize and potato on the functional guilds of non-target arthropods. Use of and type of insecticides influenced the magnitude and direction of effects; insecticde effects were much larger than those of Bt crops. These meta-analyses underscore the importance of using controls not only to isolate the effects of a Bt crop per se but also to reflect the replacement of existing agricultural practices. Results will provide researchers with information to design more robust experiments and will inform the decisions of diverse stakeholders regarding the safety of transgenic insecticidal crops. [ABSTRACT FROM AUTHOR]

Greenhouse and field studies were conducted to estimate survival rates of crawler stage Bemisia tabaci (Gennadius) Biotype B (=B. argentifolii Perring & Bellows) on cotton (Gossypium hirsutum L.) plants to enable more accurate life tables to be constructed for this important insect pest. The survival of crawlers did not differ significantly between still-air and artificial wind treatments in the greenhouse and averaged 90%. Overall, 99.5% of the crawlers settled on the abaxial surface of leaves, and 99.9% settled on the leaf where eggs were oviposited. Out of 4,125 nymphs, only five settled on leaves other than the leaf of origin, and they all moved to leaves lower on the plant. Assuming that these individuals crawled rather than fell, the mean distance moved was at least 200 mm. Using a combination of cohort-based life table studies to measure egg mortality and recruitment studies to measure egg to settled first instar mortality in the field, crawler survival was estimated to average 89.2% over three study sites in Phoenix and Maricopa, AZ. Overall results suggest that crawlers move very little on cotton and that survival of the crawler stage is relatively high under both greenhouse and field conditions. Generational mortality rates estimated from previous life table studies in the field that excluded crawler mortality would increase by only 0.8% with the addition of this minor mortality component. [ABSTRACT FROM AUTHOR]

Field studies to assess effects of transgenic crops on nontarget organisms primarily have focused on nontarget abundance and diversity, whereas few have examined effects on nontarget community function. A 5-yr field study in Arizona assessed whether transgenic cotton producing the CrylAc toxin of Bacillus thuringiensis (Bt) had an effect on the natural enemy community's impact on three key pests. Predator:prey ratios for Bemisia tabaci (Gennadius) and Lygus hesperus Knight were similar in unsprayed Bt and non-Bt cotton. Insecticide applications in positive control plots inconsistently altered ratios for B. tabaci. Predation indices based on the known feeding activity of selected predators showed that potential predator impact was unaltered by Bt cotton but was consistently depressed with insecticide applications. Sentinel eggs and pupae of Pectinophora gossypiella (Saunders) experienced the same rates of predation in both unsprayed Bt and non-Bt cotton. Cohort-based life tables for B. tabaci showed that rates of sucking predation, parasitism, and dislodgement (chewing predation in part) were unchanged by Bt cotton. Underlying experimental designs were sufficient to consistently detect changes of <20% in predator:prey ratios and predation indices and changes of <10% in rates of P. gossypiella and B. tabaci mortality with >80% power (α = 0.05). These long-term studies showed essentially no effects of Bt cotton on natural enemy function in Arizona cotton and further showed that minor reductions in density of several predator taxa in Bt cotton observed in a companion study may have little ecological meaning relative to natural enemy impact on key pests in the system. [ABSTRACT FROM AUTHOR]

A 6-yr field study assessed the long-term impact of Bt cotton producing the CrylAc δ-endotoxin on 22 taxa of foliar-dwelling arthropod natural enemies in Arizona. No chronic, long-term effects of Bt cotton were observed over multiple generations of nontarget taxa. Zero-2 taxa declined significantly in unsprayed Bt compared with non-Bt cotton each year. In contrast, positive control studies showed that insecticide applications for caterpillars and other pests in both non-Bt and Bt cotton had much greater negative effects on 10 taxa. Multivariate principal response curves supported the findings of univariate analyses for the entire natural enemy community, showing no effect of Bit cotton but large and long-lasting negative effects from the use of insecticides. Multi-year analyses provided greater statistical power and indicated significant reductions that averaged 19% in five arthropod predator taxa in unsprayed Bit compared with non-Bit cotton. Most of these reductions were likely associated with reductions in lepidopteran prey. However, results of a companion study examining natural enemy function suggest that these minor reductions in Bt cotton have little ecological meaning. Multi-year analyses showed an average significant reduction of 48% in 13 taxa for plots receiving insecticide applications. On average, a 3-yr study with four replicates per year was sufficient to discern changes of ≈20%, with 80% power in unsprayed cotton. This long-term study indicates that the effects of Bit cotton on a representative nontarget community are minor, especially in comparison with the alternative use of broad-spectrum insecticides. Guidelines for improving nontarget field studies are discussed. [ABSTRACT FROM AUTHOR]

Natural mortality is an important determinant of the population dynamics of a species, and an understanding of mortality forces should aid in the development of better management strategies for insect pests. An in situ, observational method was used to construct cohort-based life tables for Bemisia tabaci (Gennadius) Biotype B (Homoptera: Aleyrodidae) over 14 generations on cotton in central Arizona, USA, from 1997 to 1999. In descending order, median marginal rates of mortality were highest for predation, dislodgment, unknown causes, egg inviability, and parasitism. The highest mortality occurred during the 4th nymphal stadium, and the median rate of immature survival over 14 generations was 6.6%. Predation during the 4th nymphal stadium was the primary key factor. Irreplaceable mortality was highest for predation and dislodgment, with the absence of these mortality factors leading to the greatest increases in estimated net reproduction. There was little evidence of direct or delayed density-dependence for any mortality factor. Wind, rainfall, and predator densities were associated with dislodgment, and rates of predation were related to densities of Geocoris spp., Orius tristicolor (White), Chrysoperla carnea s.l. Stephens, and Lygus hesperus Knight. Simulations suggest that immigration and emigration play important roles in site-specific dynamics by explaining departures from observed population trajectories based solely on endogenous reproduction and mortality. By a direct measurement of these mortality factors and indirect evidence of adult movement, we conclude that efficient pest management may be best accomplished by fostering greater mortality during the 4th stadium, largely through a conservation of predators and by managing immigrating adult populations at their sources. [ABSTRACT FROM AUTHOR]

Field studies were conducted from 1997 to 1999 to contrast the effects of two insect growth regulators (IGRs) and conventional insecticides on natural enemy conservation in cotton within the context of alternative management strategies for Bemisia tabaci (Gennadius). Compared with an untreated control, insecticide regimes based on the initial use of the IGR buprofezin or pyriproxyfen reduced densities of eight predator taxa out of 20 examined in at least one year, including common species such as Geocoris punctipes (Say), Nabis alternatus Parshley, Chrysoperla carnea s.l., and the empidid fly Drapetis nr. divergens. Patterns of predator and pest population change relative to IGR application dates suggest that factors other than direct toxic effects, such as reduction in prey availability, were likely involved. In comparison, the use of conventional insecticides reduced populations of nearly all the predatory taxa examined in most years, including those affected by IGRs, with the impact being greater and more immediate in all cases. Predator:prey ratios were significantly increased by the use of IGRs compared with both the untreated control and a conventional insecticide regime in most instances. The application of conventional insecticides for suppression of Lygus hesperus Knight, another key pest in the system, in a split-plot design reduced densities of most predator taxa and diminished the selective advantage of the IGRs. Rates of parasitism by aphelinid parasitoids (Eretmocerus eremicus Rose and Zolnerowich and Encarsia spp.) were generally low and did not vary consistently due to B. tabaci or L. hesperus insecticide regimes over the three years. Our 3-year study demonstrates the more selective action of buprofezin and pyriproxyfen in an effective integrated control system for B. tabaci. The use of these IGRs could further facilitate biologically based management in cotton production systems. [Copyright &y& Elsevier]

A large-scale study was conducted in 1996 to evaluate and demonstrate strategies for pest management of Bemisia tabaci (Gennadius) in cotton involving different insecticide regimes, application methods, and action thresholds. Here we examined the effects of the various management systems on the abundance and activity of native natural enemies. Population densities of 18 out of 20 taxa of arthropod predators were significantly higher in regimes initiated with the insect growth regulators (IGRs) buprofezin (chitin inhibitor) or pyriproxyfen (juvenile hormone analog) compared with a regime dependent on a rotation of conventional, broad-spectrum insecticides. There were no differences in predator density between the two IGR regimes, and generally no effects due to application method or action threshold level. Predator to prey ratios were significantly higher in regimes utilizing the two IGRs compared with the conventional regime, but were unaffected by application method or threshold level. Rates of parasitism by Eretmocerus eremicus Rose and Zolnerowich and Encarsia meritoria Gahan were higher in the IGR regimes compared with the conventional regime, but were unaffected by insecticide application method, or the action threshold used to initiate applications of the IGRs. Results demonstrate the selective action of these two IGRs and suggest that their use may enhance opportunities for conservation biological control in cotton systems affected by B. tabaci , especially relative to conventional insecticide alternatives. [ABSTRACT FROM AUTHOR]

The biological control function provided by natural enemies is regarded as a protection goal that should not be harmed by the application of any new pest management tool. Plants producing Cry proteins from the bacterium, Bacillus thuringiensis (Bt), have become a major tactic for controlling pest Lepidoptera on cotton and maize and risk assessment studies are needed to ensure they do not harm important natural enemies. However, using Cry protein susceptible hosts as prey often compromises such studies. To avoid this problem we utilized pest Lepidoptera, cabbage looper (Trichoplusia ni) and fall armyworm (Spodoptera frugiperda), that were resistant to Cry1Ac produced in Bt broccoli (T. ni), Cry1Ac/Cry2Ab produced in Bt cotton (T. ni), and Cry1F produced in Bt maize (S. frugiperda). Larvae of these species were fed Bt plants or non-Bt plants and then exposed to predaceous larvae of the green lacewing Chrysoperla rufilabris. Fitness parameters (larval survival, development time, fecundity and egg hatch) of C. rufilabris were assessed over two generations. There were no differences in any of the fitness parameters regardless if C. rufilabris consumed prey (T. ni or S. frugiperda) that had consumed Bt or non-Bt plants. Additional studies confirmed that the prey contained bioactive Cry proteins when they were consumed by the predator. These studies confirm that Cry1Ac, Cry2Ab and Cry1F do not pose a hazard to the important predator C. rufilabris. This study also demonstrates the power of using resistant hosts when assessing the risk of genetically modified plants on non-target organisms. [ABSTRACT FROM AUTHOR]