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Arthropods biodiversity index in Bollgard[R] cotton (CrylAc) in Brazil/Indice de biodiversidad de artropodos en algodon Bollgard[R] (CrylAc) cultivado en la region de cerrado en Brasil/Indice de biodiversidade de artropodes em algodao Bollgard[R] (CrylAc) no Brasil.

SUMMARY

Shannon-Wiener's diversity index (SWI) was used under untreated conditions of a cotton field during the 2006/2007 crop season in the Cerrado region, Brazil. Comparison was carried out between the transgenic NuOpal[R] (BollgarcF)(CrylAc) and the non-transgenic isogenic variety DeltaOpaP. SWI was calculated for target pests, non-target herbivores and predators groups. Two sampling methods were used: whole plant observation and beat sheet. As expected, the mean number of target pests, especially Pectinophora gossypiella (Sound.) and Alabama argillacea (Hubner), was significantly smaller in Bt cotton. In the whole plant method sampling the SWI for non-tar get herbivores was significantly higher in Bt-cotton. The mean number of Anthonomus grandis (Boh.) and Edessa meditabunda (Fabr.) adults were significantly higher in NuOpal[R] with the whole plant sampling method. However, such differences were not observed with the beat sheet method. For the natural enemies, SWI and mean number of larvae and adults of the dominant predators did not show any significant difference between Bt and non-Bt cotton. These results confirm the conservation of some tritrophic interactions inside the Bt (untreated) cotton and contributes to a better sustainable management of nontarget pests by enhancement of their natural biological control.

RESUMEN

El indice de biodiversidad de Shannon-Wiener's (ISW) fue utilizado en areas dedicadas al cultivo de algodon no tratadas insecticidas. El trabajo se realizo en areas algodoneras localizadas en la region de Cerrado, Brasil. Se comparo el algodon transgenico NuOpal[R] (BollgarcPjjCrylAc) con la isolinea no transgenica DeltaOpaP. El indice de biodiversidad fue calculado para todos los insectos presentes en el agroecosistema algodonero, incluyendo los insectos plagas de la variedad Bt, convencionales y enemigos naturales. Los metodos de muestreo utilizados fueron el uso del pano de sacudida y la planta entera. Como era previsible, el valor promedio calculado de las plagas, especificamente Pectinophora gossypiella (Sound.) and Alabama argillacea (Hiibner), fue significativamente menor en el algodon Bt. El ISW para los insectos plagas fue significativamente mayor en algodon Bt con el metodo de planta entera, en tanto que la media poblacional de adultos de Anthonomus grandis (Boh.) y Edessa meditabunda (Fabr.) fue mayor en NuOpal[R] usando el mismo metodo. No obstante, esta diferencia no fue observada con el metodo de pano de sacudida. Por otra parte, el ISW, para los enemigos naturales y el valor de la media poblacional de larvas y adultos de los predadores dominantes no presentaron diferencia significativa entre el algodon Bt y el convencional. Estos resultados corroboran la conservacion de las interacciones tritroficas en el algodon Bt (no tratado con insecticidas) y aporta nuevos elementos tecnicos para manejo integrado de insectos con enfasis en su control biologico natural.

RESUMO

O indice de diversidade de Shannon-Wiener (ISW) foi utilizado em condicoes de cultivo de algodoeiro nao tratado, sem aplicacao de inseticidas durante a safra 2006/2007 no Cerrado, Brasil. Foi realizada comparacao entre NuOpal[R] (BollgarcP)(CrylAc) e sua isolinha nao transgenica. O indice foi calculado para pragas-alvo do algodao Bt, pragas nao-alvo e inimigos naturais. Foram utilizados dois metodos de amostragem: planta inteira e pano de batida. Como esperado, o numero medio de pragas-alvo, especialmente Pectinophora gossypiella (Sound.) e Alabama argillacea (Hiibner), foi significativamente menor em algodao Bt. Na amostragem por planta inteira, o ISW para herbivoros nao-alvo foi significativamente maior em algodao Bt. O numero medio de adultos de Anthonomus grandis (Boh.) e Edessa meditabunda (Fabr.) foi significativamente maior em NuOpal[R] utilizando o metodo de amostragem de planta inteira. Entretanto, esta mesma diferenca nao foi observada com o metodo do pano de batida. Para inimigos naturais, o ISW e o numero medio de larvas e adultos de predadores dominantes nao apresentou diferenca signficativa entre algodao Bt e nao-Bt. Estes resultados confirmam a conservacao de algumas interacoes tritroficas dentro do sistema algodao Bt (nao pulverizado) e contribui para um manejo de herbivoros nao-alvo sustentavel pelo incremento do seu controle biologico natural.

KEYWORDS / Bt-cotton / CrylAc / Diversity / Herbivores Non-Target / Predators / Shannon-Wiener's Index /

Introduction

Biological communities have a degree of organization that is represented by their specific abundance distribution or relative frequency of the species present in the environment. The biological diversity in one biological community has two components: species richness (existing species number) and homogeneity, which depends on the larger or smaller uniformity of the distribution frequency of existing species (Hurlbert, 1971). The importance of the use of diversity indexes is their application in monitoring studies of biological communities dynamics and structural change detection, when the community environment is modified and the species have to adapt to the modifications, so as to contribute with the conservation of biodiversity in agroecosystems (Southwood, 1995).

Genetically modified (GM) cotton varieties expressing the Bacillus thuringiensis (Bt) CrylAc protein (NuOpal[R] and DP90B) were introduced commercially in Brazil during the 2006/2007 crop season. Knowledge about the non-target species (herbivores and natural enemies) present in the Bt-cotton in different field conditions is still incipient in Latin America, in spite of the economic importance of knowing the biological diversity and maintaining a biological control during the introduction of GM crops (Romeis et al., 2008; Lovei et al., 2009; Adenle, 2012).

Pest resistant GM varieties were initially grown in countries such as the USA, Argentina, Australia, China, Mexico and South Africa, allowing fewer insecticide applications, reduction in production costs and reduction of the risks to human health (Shelton et al., 2002; Naranjo, 2009). Another aspect is the promotion and the preservation of natural enemies, contributing to integrate pest management systems with a strong biological control component and assessment of risk of Bt-cotton to non-target arthropods, leading to a sustainable production and preserving the environment (Romeis et al., 2006; 2008; Sarvjeet, 2012).

There are few published studies conducted about the impact of the Bt-cotton varieties on the diversity of arthropods, especially with respect to the values found in diversity indexes, like the Shannon-Wiener's index. Using this index, no difference in arthropod biodiversity between Bt and non-Bt cotton was shown by Li et al. (2002), or an increase in the arthropod communities diversity and pest sub-communities (Men et al., 2003). In Brazil, Ramiro and Faria (2006) observed no significant differences in the total predator specimens collected from Bollgard[R] cotton as compared to treatments with Delta Pine Acala 90, with or without chemical control of caterpillars.

The objective of this research was to study the arthropod biodiversity associated with Bt-cotton (NuOpal[R]), as compared to the non-transgenic isogenic DeltaOpal[R] in the absence of insecticide sprays, promoting the knowledge of structural changes in arthropod communities in the Bt and non-Bt cotton, constituting a basis for the regulation of population dynamics of insect pests and the damage caused by such pests. This paper presents the first study of biodiversity of non-target herbivores and natural enemies (mainly predators) sampled with two methods: whole plant and beat sheet, in the Brazilian Cerrado Biome (Savannah) region, Mato Grosso do Sul State, Brazil. A faunistic analysis of the genera and species found on Bt-cotton compared with non Bt-cotton using the Shannon-Wiener's index is discussed.

Materials and Methods

This research was conducted at the Faculdade de Ciencias Agrarias (FCA), Universidade Federal da Grande Dourados, in Dourados, Mato Grosso do Sul,, Brazil, between February and June 2007. An irrigation system was installed in order to facilitate crop development during the experiment. Basic and side dressing fertilizations were performed with 400kg x [ha.sup.-1] NPK (8-20-20). Conventional planting system was adopted. Soil tillage was accomplished on February 14, 2007, before seeding by plowing and harrowing,. Seeds of the NuOpal[R] (Bt) and DeltaOpal[R] (non-Bt) varieties used in the experiment were provided by MDMSeeds of Cotton[R], and were pre-treated with the fungicides Euparen[R] (tolylfluanid) (200g/100kg seeds), Monceren[R] (pencycuron) (200g/100kg seeds), and Baytan[R] (triadimenol) (40ml/20Kg seeds), in order to control diseases that cause damping-off. Both varieties were manually seeded on February 15, 2007, at a density of 13 seeds/m and a row spacing of 0.90m. Emergence occurred 4 days later. Weed control was performed by hand-weeding during the entire cycle for both varieties. Blitz[R] baits (fipronil) were applied at the beginning of the crop cycle on the surroundings of the experimental area to control leaf-cutting ants of the genera Atta and Acromyrmex.

The total experimental area was 18x72m (0.12ha) with 32 sub-areas (plots) that were demarcated by random drawing, 16 for each treatment: DeltaOpal[R] and NuOpal[R]. Each Each sub-area comprised five rows of the treatment variety, measuring 4.5x9m. The three central rows were sampled; one row at each end of each subarea was the border of the sampling unit. In order to reduce the incidence of Anthonomus granais (Boheman, 1843) during the experiment, 23 traps were installed containing grandlure pheromone + insecticide, to capture boll weevils in the vicinity of the experiment area.

The sampling and quantification of the Bollgard[R] technology target insects, non-target pests, and natural enemies found were performed every seven days during the entire evaluation period, from the crop's VE stage (emergence), on February 21, until June 13. Two visual sampling methods were used: 'beat sheet', recommended by (Degrande et al., 2003), and 'whole plant'. Seventeen whole plant samplings and 8 beat sheet samplings were made for each treatment, preparing 272 replicates for the whole plant method and 128 for the beat sheet method in each treatment over the experimental period.

In the beat sheet method, samplings were taken in the crop inter-row between the three central rows of each sub area, at a random point, totaling 16 points per treatment and observation date. The beat sheet was white to facilitate insect visualization; sheet width matched the crop row spacing (0.9m), had a lm length, and was adjusted so as to cover the inter-rows. Then, both rows were vigorously shaken, causing the insects, either immature or adult, to fall onto the sheet, allowing them to be visualized, counted, and identified at the family and/or species level while still in the field. The presence of the parasitoid Catolaccus granais (Burks, 1954) and the target lepidopteran Pectinophora gossypiella was quantified in this method by the number of damaged reproductive structures (bolls) fallen onto the beat sheet. The bolls were then opened to reveal individuals of those insects.

In the whole plant evaluation method, ten plants were evaluated separately on the three central rows of each sub area, i.e., 160 plants per treatment and observation date, by quantifying and identifying the insects sampled at the family and/or species level while still in the field.

In both methods, when necessary, those insects that could not be identified in the field were collected and placed in a recipient with 70% ethanol and taken and after taken to the laboratory for later identification. Samplings for Heliothis virescens and Alabama argillacea eggs were made with the whole plant method.

The diversity in Bt and nonBt cotton with both sampling methods was based on calculations of frequency indices, constancy, abundance, and dominance (Silveira-Neto et al., 1976), considering the number of small (<1.0cm) and large caterpillars (>1.0cm), larvae, nymphs, and adults. Absolute frequency was defined as the total number of specimens observed in the various sampling conditions.

Constancy was defined as the percentage of samples in which a given species was present (Uramoto et al., 2005). After the constancy percentages over the sampling periods were obtained, the species were grouped into three categories: 'constant' (w), present in more than 50% of the weekly observations; 'accessory' (y), present in 25 to 50% of the observations; and 'accidental' (z), present in less than 25% of the observations.

Abundance is the number of individuals of a given species divided by the surface or volume unit, and may vary in space and time (Silveira-Neto et al., 1976). In order to estimate abundance, the limits established by the confidence interval (Cl) at 5 and 1% probabilities were used, and the following five classes were determined: 'rare' (r) with a number of individuals in the species smaller than the lower Cl limit at 1% probability; 'dispersed' (d) with a number of individuals between the lower limits of the confidence intervals at 1% and 5% probability; 'common' (c) within the confidence interval at 5%; 'abundant' (a), between the upper limits of the confidence intervals at 5% and 1% probability; and 'very abundant' (va) with a number of individuals greater than the upper Cl limit at 1% probability.

An organism is considered dominant when it receives impact from the environment and becomes adapted to it (Silveira-Neto et al., 1976). In the present study, a species was considered 'dominant' when its relative frequency was >1/S, where S: total number of species found in the sampling period.

In order to compare the mean differences between groups of target pests, nontarget pests, natural enemies and individuals of dominant species within each group, the development stage of the specimens was taken into consideration. The comparison between Bt and non-Bt treatments was calculated based on the mean of each treatment throughout the entire sampling period. The Student's t test was later used at a significance level [alpha]=5%. The original data were not normally distributed, and the test was applied to the data transformed to [square root of X+0.5], thus meeting the assumptions associated with the model.

Target pest, non-target pest and natural enemy diversity in Bt and non-Bt-cotton environments were studied using Shannon-Wiener's index with a correction factor and natural logarithm (Poole 1974), by means of specimen frequency. This index measures the degree of uncertainty in predicting to which species will belong a randomly selected individual, from a sample with S species and N individuals (Silveira-Neto et al., 1976).

The smaller the Shannon-Wiener's index value, the smaller the degree of uncertainty, therefore reflecting the low diversity of a sample. Diversity tends to be higher for higher index values (Uramoto et al., 2005). Student's t test was used to check whether the species diversity difference between those environments was significant at [alpha]=5%. Data were analyzed using the statistical software package SPSS[R] (SPSS, 2006).

Results and Discussion

A total of 55 species were observed, distributed among 11 orders and 32 families, and were divided into three groups: target pests, non-target pests, and natural enemies (Table I). The very abundant (va) species of non target herbivores, both in NuOpal[R] and DeltaOpal[R] cotton with the whole plant and beat sheet methods, were Horciasoides nobilellus (Bergston, 1883) and Dysdercus sp. The species Bemisia tabaci (Gennadius, 1889) and Agallia albidula (Uhler, 1895) were very abundant in Bt and nonBt cotton only with the whole plant method. The species Edessa meditabunda (Fabr., 1794), however, was very abundant in both varieties, but only with the beat sheet method. The non-target species Anthonomus grandis (Boheman, 1843) was found to be abundant in Bt cotton with both sampling methods.

The fact of B. tabaci was observed as the most abundant species with similar population densities between Bt and non-Bt cotton in the whole plant method (Naranjo, 2005) can be attributed to the behavior of this insect. Its quick flight when the plant is touched, made it difficult to be sampled by beat sheet, demonstrating the importance of selecting the adequate sampling method to monitor non-target insects with an economic importance in transgenic varieties in the field (Naranjo et al., 2005; Wade et al., 2006). Another point that will be considered is the differences in 'leaf hair' between the cotton varieties and in the mode of action of Bt toxins inserted in these genetically modified cotton varieties, which can influence the abundance of insects, as observed in Australia (Whitehouse et al., 2007), with high numbers of whitefly in Bt cotton (VipCotton).

Dominance was found in the target pest group for the species A. argillacea and P. gossypiella in non-Bt cotton, with both sampling methods. The presence of the species H. virescens was also detected, but at a low frequency when compared with the other two target pests, i.e., one caterpillar in DeltaOpal[R] with both sampling methods. The non-target herbivores species, A. grandis, H. nobilellus, Euschistus heros (Fabr., 1798) and Dysdercus sp. were dominant in both varieties with both sampling methods, while B. tabaci and A. albidula were dominant in both NuOpal[R] and DeltaOpal[R] only with the whole plant method. For the pentatomid species Nezara viridula (L., 1758) and E. meditabunda, the dominance was observed in both varieties, but only with the beat sheet method. In the whole plant sampling, the sucking herbivore species E. meditabunda was dominant in NuOpal[R] only, while the chewing herbivore Diabrotica speciosa (Germar, 1824) was dominant only in the Bt variety, with the beat sheet sampling (Table I).

These dominance results showed the reduction in feeding competition between nontarget herbivores and target insects controlled by the Bollgard[R] technology, as a reduction in competition for food resources with target caterpillars controlled by the CrylAc toxin and the sucking herbivores like the pentatomids and mirids. They show the importance of the knowledge of bioecology interaction between insects in an agroecosystem.

Also, the sampling method used can influence the quantification of each insect species affecting the Bt and non-Bt varieties, considering the behavior of each species and their migration from soybean varieties to cotton (Lu et al., 2010), as in the case of some pentatomids, searching food resources in the cotton-soybean agroecosystem. The correct selection of the sampling method leads to real interpretations about the effect of the GM plant on the arthropod population, and consequently on the biological control, which may be potentiated with the adoption of Bt crops.

Considering the constancy throughout the sampling period, A. argillacea had constant incidence only in non-Bt cotton with the whole plant method. The constant non-target herbivore species in both NuOpal[R] and DeltaOpal[R] in both samplings were D. speciosa, H. nobilellus, E. meditabunda, E. heros, N. viridula (L., 1758) and Dysdercus sp., while B. tabaci, A. albidula, Piezodorus guildini (Westwood, 1837), Jansonius boggianii subaeneus and Frankliniella sp. were constant in both Bt and non-Bt cotton with the whole plant sampling, and A. grandis and Pseudoplusia includens (Walker, 1857) were constant in both types of cotton with beat sheet sampling. The non-target herbivores species Lagria villosa (Fabr., 1783), Astylus variegatus (Germar, 1824), Neomegalotomus parvus (Westwood, 1842), A. albidula, Piezodorus guildini (Westwood, 1837) and Spodoptera eridania (Cramer, 1782) were constant only in Bt cotton with the whole plant method (Table I).

With regard to non-target herbivores diversity, the Shannon-Wiener's index with the whole plant method for Bt cotton showed statistically significant differences, being higher than non-Bt, thus demonstrating that the NuOpal[R] variety showed higher diversity of non-target herbivores than the DeltaOpal[R] variety with the whole plant sampling. However, in the beat sheet method, the index did not show significant difference (Table II). This result in the diversity index can be explained by fact that the mean number of the non-target herbivores A. grandis

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and E. meditabunda adults in the whole plant method was significantly different between Bt and non-Bt cotton, being higher in Bt cotton than non-Bt (Table III). Yet, such difference was not observed with the beat sheet method (Table IV). The mean number of target pest individuals observed with both sampling methods was significantly smaller in NuOpal[R] than in DeltaOpal[R].

The results of the faunistic analysis of non-target species of CrylAc (Bollgard[R] cotton) sampled between the NuOpal[R] and DeltaOpal[R] environments demonstrate that abundance, dominance and constancy of the species can be attributed to several factors, such as the lack of insecticidal activity of the transgenic variety (CrylAc) on non-target herbivores and predators in NuOpal[R], which can affect directly the diversity and trophic interactions of these insects, promoting the knowledge of these tritrophic interactions and the integration of Bt cotton use and biological control (Li et al., 2002; Romeis et al., 2008).

Among the natural enemies sampled, predators were mainly present. The predators Araneae, Cycloneda sanguinea (L., 1763) and Scymnus sp. were very abundant both in NuOpal[R] and DeltaOpal[R] with both sampling methods. With the beat sheet method, the parasitoid species C. grandis was abundant both in NuOpal[R] and DeltaOpal[R], and the predator bug Orius sp. was abundant in non Bt cotton only.

Dominant natural enemies both in Bt and non-Bt cotton, with both the whole plant and beat sheet methods, were Araneae, C. sanguinea, Scymnus sp., Geocoris sp. and C. grandis. On the other hand, the predator Orius sp. was dominant in both NuOpal[R] and DeltaOpal[R] with the beat sheet method. However, this bug was only dominant in DeltaOpal[R] with the whole plant sampling. The beneficial arthropods Araneae, C. sanguinea, Scymnus sp. and Geocoris sp. Did not vary in both Bt and non-Bt cotton with both sampling methods. However, in the beat sheet, the predators Doru luteipes (Scudder, 1876) and Zelus longipes (L., 1767) were constant in DeltaOpal[R] only, while Chrysoperla sp. was constant in both Bt and nonBt cotton (Table I).

The faunistic analysis for the natural enemies is mainly correlated with the tritrophic interactions and the direct and indirect effects of Bt toxin plants on the preys and hosts of these benefical insects (Shelton et al., 2002). Another point to be considered is the traits adopted in the transgenic varieties (Wan et al., 2002; Yang et al., 2005), like the application or not of insecticides with regard to the control level to the non-target herbivores of Bt plants (Degrande, 2004; Thomazoni et al., 2010), the use of selective insecticides, and the sampling method adopted correlated with the behavior and bioecology of the natural enemy, which can be influence the diversity of these insects (Men et al., 2003), as demonstrated in this study, in the beat sheet method for Orius sp., which was dominant in both NuOpal[R] and DeltaOpal[R] and was only dominant in DeltaOpal[R] with the whole plant sampling.

With regard to natural enemies diversity in both sampling methods, the Shannon-Wiener's index and also the mean number of natural enemies was not significantly different between cotton varieties using both sampling methods (Table II). The mean number of larvae and adults in the dominant genera and species of the predators C. sanguinea, Scymnus sp., Chrysoperla sp., Geocoris sp., Orius sp., Araneae and C. granais did not show significant differences between Bt and non-Bt cotton in any of the sampling methods (Table V).

The dominance of predator Chrysoperla sp. in Bt cotton with both sampling methods, may indicate that this insect possibly did not suffer a negative impact from the Bt toxin present in the transgenic variety (Hilbeck et al., 2006). In contrast to our results, a small difference in Geocoris sp. population density between Bt and non-Bt cotton, both without chemical control application, was observed by Naranjo (2005). In the case of Orius sp. populations, the lack of chemical control application during the entire development cycle of both varieties can influence predator abundance, and influenced this genus, which was abundant in both Bt and nonBt cotton. This result was confirmed by the measure of the mean number of individuals of Orius sp., and the same result was observed with Araneae in both sampling methods. But other studies have shown a higher mean number of these predators in Bt cotton than in non Bt cotton (Wan et al., 2002; Hagerty et al., 2005).

The similarity in the mean number of individuals of the Chrysopidae family between Bt and non-Bt cotton was also observed in Australia (Whitehouse et al., 2005), and the presence of individuals of this family was also observed in Bt cotton (Sisterson et al., 2004). However, Hagerty et al. (2005) found that chrysopid populations belonging to the Chrysopidae and Hemerobiidae families were more abundant in Bollgard[R] cotton when compared with non-Bt cotton, showing a negative effect of Bt cotton on the diversity of these natural enemies.

A lack of significant difference in the mean number of sampled Coccinellidae was also observed in China (Yang et al., 2005). However, in other countries (Hagerty et al., 2005; Hofs et al., 2005) differences in the mean number of specimens from this family of predators have been observed. Such difference in results can be attributed to the number of prey sampled between Bt and nonBt cotton, whose development was favored by the lack of action of insecticides (Marvier et al., 2007) that are otherwise commonly applied for their control, showing the importance of integrating pest management tactics (Romeis et al., 2006, 2008), in this case, Bt cotton and biological control.

This biodiversity study was conducted to better understand the biology and ecology of the predator/pest interactions in Bt and non-Bt cotton varieties without application of insecticides, in a savannah agroeco-system in Brazil, being relevant because the arthropods play an important part in the structure and operation of the ecosystems and the maintenance of the biological diversity (Tscharntke and Clough, 2007; Scherr and McNeely, 2008; Sarvjeet, 2012). With the crescent introduction of the Bt cotton varieties in Brazil, it is crucial to quantify the diversity of insect communities present in Bt and non-Bt cotton plots and to determine how these communities are influenced by environmental changes provoked by natural causes or by human activity, like agronomic practices such a insecticide control for non-herbivores insects, and how these affect the biodiversity by tritrophic interactions that can contribute with the reduction of target pests, as natural enemies are the main cause of insect mortality in agroecosystems (Parra, 2000; Peixoto et al., 2007). In this way, this research can show how to integrate natural control with the transgenic plants, promoting the conservation of the beneficial insects, using the different monitoring sampling and diversity indexes.

Conclusions

NuOpal[R] (CrylAc) is efficient in the control of target species (P. gossypiella, H. virescens and A. argillacea) under cultivation conditions of the Brazilian Cerrado biome (savannah) without insecticide sprays.

The whole plant sampling method, as detected by the diversity indexes, has a higher diversity of the non-target herbivores A. granais and E. meditabunda in Bt cotton (CrylAc).

The natural enemies diversity on the non-sprayed Bt cotton (CrylAc) shows tritrophic interactions, and the conservation potential and benefits on that agroecossystem.

Moreover, this research demonstrated that the faunistic analysis and the diversity index of Shannon-Wiener can be used in studies of risk assessment of Bt varieties in non-target arthropod populations in Brazil.

ACKNOWLEDGEMENTS

The authors thank Sergio Vanin (Universidade de Sao Paulo) for identifying the chrysomelid Jansonius boggianii subaeneus, Rogerio Silvestre and Manoel Fernando Demetrio (Universidade Federal da Grande Dourados) for identifying the ants (Solenopsis invicta e Atta sp.), MDM-Sementes de Algodao[R] for the seeds of both varieties used in the experiment and CNPq for the grant awarded to the first author.

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Received: 25/09/2012. Modified: 09/12/2013. Accepted: 12/12/2013.

Danielle Thomazoni. Biologist and Ph.D. in Sciences (Entomology), Universidade Federal de Grande Dourados (UFGD), Brazil. Research Entomologist, Instituto Mato-grossense do Algodao (IMAmt), Brazil. Address: Rodovia BR 070 Km 265, Campo Experimental, Zona Rural, Primavera do Leste, MT, Brazil. 78850-000. e-mail: daniellethomazoni@ imamt.com.br

Miguel Ferreira Soria. Agronomist and Ph.D. in Vegetal Production, UFGD, Brazil. Research Entomologist, IMAmt, Brazil.

Paulo Eduardo Degrande. Agronomist and Ph.D. in Sciences (Zoology), Universidade de Sao Paulo, Brazil. Professor, UFGD, Brazil.

Odival Faccenda. Mathematician and Ph.D. in Agronomy (Energy in Agriculture), Universidade Estadual Paulista Julio de Mesquita Filho, Brazil. Professor, Universidade Estadual de Mato Grosso do Sul, Brazil.

Pierre Jean Silvie. Biologist and Ph.D. in Entomology, Centre de Cooperation Internationale en Recherche Agronomique Pour le Development (ORAD), France. Research Entomologist, CIRAD, Montpellier, France.
TABLE I
FAUNISTIC ANALYSIS OF GROUPS OF TARGET PESTS, NON-TARGET PESTS, AND
NATURAL ENEMIES BY ORDER, FAMILY, AND SPECIES, SAMPLING METHOD, AND
TYPE OF COTTON

Group           Order/Family      Species      Stage (1)

Target       Lepidoptera/      Alabama           SC+LC
pests          Noctuidae         argillacea
             Lepidoptera/      Heliothis         SC+LC
               Noctuidae         virescens
             Lepidoptera/      Pectinophora       Cat
               Gelechiidae       gossypiella

Total

Non-target   Coleoptera/       Cerotoma           Ad
pests          Chrysomelidae     arcuata
             Coleoptera/       Chrysomelidae      Ad
               Chrysomelidae     sp.l
             Coleoptera/       Diabrotica         Ad
               Chrysomelidae     speciosa
             Coleoptera/       Jansonius          Ad
               Chrysomelidae     boggianii
                                 subaeneus
             Coleoptera/       Maecolaspis        Ad
               Chrysomelidae     sp.
             Coleoptera/       Megascelis sp.     Ad
               Cicindellidae
             Coleoptera/       Anthonomus        L+Ad
               Curculionidae     granais
             Coleoptera/       Lagria villosa     Ad
               Lagriidae
             Coleoptera/       Astylus            Ad
               Melyridae         variegatus
             Hem iptera/A      Bemisia tabaci     Ad
               leyroidade
             Hemiptera/        Neomegalotomus     Ad
               Alydidae          parvus
             Hemiptera/        Agallia            Ad
               Cicadellidae      albidula
             Hemiptera/        Hypselonotus       Ad
               Coreidae          sp.
             Hemiptera/        Oxycarenus sp.     Ad
               Lygaeidae
             Hemiptera/        Horciasinus        Ad
               Miridae           signoreti
             Hemiptera/        Horcias            Ad
               Miridae           nobilellus
             Hemiptera/        Chinavia spp.     N+Ad
               Pentatomidae
             Hemiptera/        Edessa            N+Ad
               Pentatomidae      meditabunda
             Hemiptera/        Euschistus        N+Ad
               Pentatomidae      heros
             Hemiptera/        Nezara            N+Ad
               Pentatomidae      viridula
             Hemiptera/        Piezodorus        N+Ad
               Pentatomidae      guildini
             Hemiptera/        Dysdercus sp.     N+Ad
               Pyrrhocoridae
             Lepidoptera/      Spodoptera        SC+LC
               Noctuidae         eridania
             Lepidoptera/      Spodoptera        SC+LC
               Noctuidae         frugiperda
             Lepidoptera/      Pseudoplusia      SC+LC
               Noctuidae         indudes
             Orthoptera/       Gryllus sp.        Ad
               Gryllidae
             Orthoptera/       Tettigoniidae      Ad
               Tettigoniidae     sp.l
             Thysanoptera/     Frankliniella      Ad
               Thripidae         sp.

Total

Natural      Araneae           Araneae            Ad
enemies      Coleoptera/       Callida sp.        Ad
               Carabidae
             Coleoptera/       Lebia concinna     Ad
               Carabidae
             Coleoptera/       Cycloneda         L+Ad
               Coccinellidae     sanguinea
             Coleoptera/       Eriopsis          L+Ad
               Coccinellidae     connexa
             Coleoptera/       Hyperaspis         Ad
               Coccinellidae     festiva
             Coleoptera/       Olla v-nigrum      Ad
               Coccinellidae
             Coleoptera/       Scymnus sp.       L+Ad
               Coccinellidae
             Dermaptera/       Doru luteipes      Ad
               Forficulidae
             Diptera/          Condylostylus      Ad
               Dolichopodidae    sp.
             Diptera/          Toxomerus sp.     L+Ad
               Syrphidae
             Hemiptera/        Orius sp.          Ad
               Anthocoridae
             Hemiptera/        Geocoris sp.       Ad
               Lygaeidae
             Hemiptera/        Nabis sp.          Ad
               Nabidae
             Hemiptera/        Podisus sp.       N+Ad
               Pentatomidae
             Hemiptera/        Repipta sp.        Ad
               Reduviidae
             Hemiptera/        Zelus              Ad
               Reduviidae        armillatus
             Hemiptera/        Zelus longipes     Ad
               Reduviidae
             Hymenoptera/      Solenopsis         Ad
               Formicidae        invicta
             Hymenoptera/      Catolaccus          L
               Pteromalidae      grandis
             Mantodea/         Mantidae sp.l      Ad
               Mantidae
             Neuroptera/       Chrysoperla         L
               Chrysopidae       sp.
             Neuroptera/       Nusulala sp.        L
               Hemerobiidea
             Neuroptera/       Mantispidae        Ad
               Mantispidae       sp.l

Total

Grand total

                                                   Sampling method

                                                     Whole plant

Group           Order/Family      Species      NuOpal[R]   DeltaOpal[R]
                                               FC(A)D (2)  FC(A)D (2)

Target       Lepidoptera/      Alabama            9 yn      55 w(c)s
pests          Noctuidae         argillacea
             Lepidoptera/      Heliothis           0         1 z(c)n
               Noctuidae         virescens
             Lepidoptera/      Pectinophora        0        39 y(c)s
               Gelechiidae       gossypiella

Total                                              9            95

Non-target   Coleoptera/       Cerotoma          5 z(d)n     2 z(d)n
pests          Chrysomelidae     arcuata
             Coleoptera/       Chrysomelidae     2 z(d)n     2 z(d)n
               Chrysomelidae     sp.l
             Coleoptera/       Diabrotica       52 w(c)n    45 w(c)n
               Chrysomelidae     speciosa
             Coleoptera/       Jansonius        37 w(c)n    38 w(c)n
               Chrysomelidae     boggianii
                                 subaeneus
             Coleoptera/       Maecolaspis      19 y(d)n    10 y(d)n
               Chrysomelidae     sp.
             Coleoptera/       Megascelis sp.    1 z(d)n     2 z(d)n
               Cicindellidae
             Coleoptera/       Anthonomus      235 y(ma)s  154 y(c)s
               Curculionidae     granais
             Coleoptera/       Lagria villosa    2 z(d)n     3 z(d)n
               Lagriidae
             Coleoptera/       Astylus          26 y(c)n    10 z(d)n
               Melyridae         variegatus
             Hem iptera/A      Bemisia tabaci  903 w(ma)s  856 w(ma)s
               leyroidade
             Hemiptera/        Neomegalotomus      0         3 z(d)n
               Alydidae          parvus
             Hemiptera/        Agallia         315 w(ma)s  261 w(ma)s
               Cicadellidae      albidula
             Hemiptera/        Hypselonotus        0            0
               Coreidae          sp.
             Hemiptera/        Oxycarenus sp.    5 z(d)n     2 z(d)n
               Lygaeidae
             Hemiptera/        Horciasinus       1 z(d)n     1 z(d)n
               Miridae           signoreti
             Hemiptera/        Horcias         611 w(ma)s  549 w(ma)s
               Miridae           nobilellus
             Hemiptera/        Chinavia spp.     5 z(d)n     2 z(d)n
               Pentatomidae
             Hemiptera/        Edessa          129 w(c)s    74 w(c)n
               Pentatomidae      meditabunda
             Hemiptera/        Euschistus      114 w(c)s    93 w(c)s
               Pentatomidae      heros
             Hemiptera/        Nezara           63 w(c)n    61 w(c)n
               Pentatomidae      viridula
             Hemiptera/        Piezodorus       38 w(c)n    17 w(c)n
               Pentatomidae      guildini
             Hemiptera/        Dysdercus sp.   217 w(a)s   219 w(ma)s
               Pyrrhocoridae
             Lepidoptera/      Spodoptera        5 z(d)n     9 y(d)n
               Noctuidae         eridania
             Lepidoptera/      Spodoptera        4 y(d)n     6 y(d)n
               Noctuidae         frugiperda
             Lepidoptera/      Pseudoplusia      4 y(d)n    13 y(d)n
               Noctuidae         indudes
             Orthoptera/       Gryllus sp.       3 z(d)n     4 z(d)n
               Gryllidae
             Orthoptera/       Tettigoniidae       0         1 z(d)n
               Tettigoniidae     sp.l
             Thysanoptera/     Frankliniella    50 w(c)n    43 w(c)n
               Thripidae         sp.

Total                                             2846         2480

Natural      Araneae           Araneae         152 w(va)s  185 w(va)s
enemies      Coleoptera/       Callida sp.      13 z(c)n    16 z(c)n
               Carabidae
             Coleoptera/       Lebia concinna    3 z(d)n     5 z(d)n
               Carabidae
             Coleoptera/       Cycloneda        74 w(va)s  74 w(va)s
               Coccinellidae     sanguinea
             Coleoptera/       Eriopsis          4 z(d)n     5 z(d)n
               Coccinellidae     connexa
             Coleoptera/       Hyperaspis        9 z(c)n     7 y(d)n
               Coccinellidae     festiva
             Coleoptera/       Olla v-nigrum     3 z(d)n     5 z(d)n
               Coccinellidae
             Coleoptera/       Scymnus sp.     191 w(va)s  174 w(va)s
               Coccinellidae
             Dermaptera/       Doru luteipes     7 y(c)n    12 y(c)n
               Forficulidae
             Diptera/          Condylostylus     1 z(d)n     1 z(d)n
               Dolichopodidae    sp.
             Diptera/          Toxomerus sp.     7 y(c)n     8 y(d)n
               Syrphidae
             Hemiptera/        Orius sp.        27 y(c)n    45 y(c)s
               Anthocoridae
             Hemiptera/        Geocoris sp.     42 w(c)s    53 w(c)s
               Lygaeidae
             Hemiptera/        Nabis sp.         2 z(d)n        0
               Nabidae
             Hemiptera/        Podisus sp.       2 z(d)n     3 z(d)n
               Pentatomidae
             Hemiptera/        Repipta sp.       1 z(d)n     2 z(d)n
               Reduviidae
             Hemiptera/        Zelus             1 z(d)n     3 z(d)n
               Reduviidae        armillatus
             Hemiptera/        Zelus longipes   12 y(c)n    10 y(c)n
               Reduviidae
             Hymenoptera/      Solenopsis       25 y(c)n    17 y(c)n
               Formicidae        invicta
             Hymenoptera/      Catolaccus       45 z(c)s    39 z(c)s
               Pteromalidae      grandis
             Mantodea/         Mantidae sp.l     2 z(d)n     1 z(d)n
               Mantidae
             Neuroptera/       Chrysoperla      28 y(c)s    21 y(c)n
               Chrysopidae       sp.
             Neuroptera/       Nusulala sp.      2 z(d)n     8 y(d)n
               Hemerobiidea
             Neuroptera/       Mantispidae       1 z(d)n        0
               Mantispidae       sp.l

Total                                             654          694

Grand total                                       3509         3269

                                                   Sampling method

                                                     Beat sheet

Group           Order/Family      Species      NuOpal[R]   DeltaOpal[R]
                                               FC(A)D2     FC(A)D (2)

Target       Lepidoptera/      Alabama             0         31y(c)s
pests          Noctuidae         argillacea
             Lepidoptera/      Heliothis           0          lz(c)n
               Noctuidae         virescens
             Lepidoptera/      Pectinophora        0         35y(c)s
               Gelechiidae       gossypiella

Total                                              0            67

Non-target   Coleoptera/       Cerotoma            0            0
pests          Chrysomelidae     arcuata
             Coleoptera/       Chrysomelidae       0         1 z(d)n
               Chrysomelidae     sp.l
             Coleoptera/       Diabrotica      35 w(c)s     26 w(c)n
               Chrysomelidae     speciosa
             Coleoptera/       Jansonius       13 y(c)n     21 y(c)n
               Chrysomelidae     boggianii
                                 subaeneus
             Coleoptera/       Maecolaspis         0            0
               Chrysomelidae     sp.
             Coleoptera/       Megascelis sp.      0         1 z(d)n
               Cicindellidae
             Coleoptera/       Anthonomus      47 w(a)s     45 w(c)s
               Curculionidae     granais
             Coleoptera/       Lagria villosa   8 w(d)n      8 y(d)n
               Lagriidae
             Coleoptera/       Astylus         19 w(c)n     13 y(c)n
               Melyridae         variegatus
             Hemiptera/A       Bemisia tabaci      0            0
               leyroidade
             Hemiptera/        Neomegalotomus   1 w(r)n      1 z(d)n
               Alydidae          parvus
             Hemiptera/        Agallia         11 w(c)n     12 z(c)n
               Cicadellidae      albidula
             Hemiptera/        Hypselonotus     1 z(r)n         0
               Coreidae          sp.
             Hemiptera/        Oxycarenus sp.   3 y(r)n      2 y(d)n
               Lygaeidae
             Hemiptera/        Horciasinus      7 y(d)n      7 y(d)n
               Miridae           signoreti
             Hemiptera/        Horcias         142w(ma)s   150 w(ma)s
               Miridae           nobilellus
             Hemiptera/        Chinavia spp.    6 y(d)n      2 y(d)n
               Pentatomidae
             Hemiptera/        Edessa          61 w(ma)s    75 w(ma)s
               Pentatomidae      meditabunda
             Hemiptera/        Euschistus      40 w(c)s     31 w(c)s
               Pentatomidae      heros
             Hemiptera/        Nezara          40 w(c)s     31 w(c)s
               Pentatomidae      viridula
             Hemiptera/        Piezodorus       6 w(d)n      6 y(d)n
               Pentatomidae      guildini
             Hemiptera/        Dysdercus sp.   99 w(ma)s   165 w(ma)s
               Pyrrhocoridae
             Lepidoptera/      Spodoptera       9 w(d)n     11 y(c)n
               Noctuidae         eridania
             Lepidoptera/      Spodoptera          0         4 z(d)n
               Noctuidae         frugiperda
             Lepidoptera/      Pseudoplusia     7 w(d)n     12 w(c)n
               Noctuidae         indudes
             Orthoptera/       Gryllus sp.         0         1 z(d)n
               Gryllidae
             Orthoptera/       Tettigoniidae    2 y(r)n         0
               Tettigoniidae     sp.l
             Thysanoptera/     Frankliniella       0            0
               Thripidae         sp.

Total                                             557          625

Natural      Araneae           Araneae         58 w(va)s    72 w(va)s
enemies      Coleoptera/       Callida sp.      1 z(d)n      1 z(r)n
               Carabidae
             Coleoptera/       Lebia concinna   1 z(d)n      2 y(r)n
               Carabidae
             Coleoptera/       Cycloneda       44 w(va)s    44 w(va)s
               Coccinellidae     sanguinea
             Coleoptera/       Eriopsis            0            0
               Coccinellidae     connexa
             Coleoptera/       Hyperaspis       1 z(d)n         0
               Coccinellidae     festiva
             Coleoptera/       Olla v-nigrum    2 z(d)n      1 z(r)n
               Coccinellidae
             Coleoptera/       Scymnus sp.     92 w(va)s    82 w(va)s
               Coccinellidae
             Dermaptera/       Doru luteipes    4 y(d)n      7 w(d)n
               Forficulidae
             Diptera/          Condylostylus       0            0
               Dolichopodidae    sp.
             Diptera/          Toxomerus sp.    1 z(d)n         0
               Syrphidae
             Hemiptera/        Orius sp.       23 y(c)s     41 y(a)s
               Anthocoridae
             Hemiptera/        Geocoris sp.    20 w(c)s     28 w(c)s
               Lygaeidae
             Hemiptera/        Nabis sp.        1 z(d)n         0
               Nabidae
             Hemiptera/        Podisus sp.      3 y(d)n      5 y(d)n
               Pentatomidae
             Hemiptera/        Repipta sp.         0            0
               Reduviidae
             Hemiptera/        Zelus               0            0
               Reduviidae        armillatus
             Hemiptera/        Zelus longipes   3 y(d)n      6 w(d)n
               Reduviidae
             Hymenoptera/      Solenopsis       1 z(d)n      1 z(r)n
               Formicidae        invicta
             Hymenoptera/      Catolaccus      45 z(va)s    39 z(a)s
               Pteromalidae      grandis
             Mantodea/         Mantidae sp.l       0         1 z(r)n
               Mantidae
             Neuroptera/       Chrysoperla     26 w(c)s     20 w(c)n
               Chrysopidae       sp.
             Neuroptera/       Nusulala sp.     2 y(d)n      5 y(d)n
               Hemerobiidea
             Neuroptera/       Mantispidae         0            0
               Mantispidae       sp.l

Total                                             328          355

Grand total                                       885          1047

(1) SC: small caterpillar, LC: large caterpillar, Cat: caterpillar,
L: larva, N: nymph, Ad: adult. (2) F: total number observed in
different sampling conditions; C (constancy): w: constant, y:
accessory, z: accidental; A (abundance): va: very abundant, a:
abundant, c: common, d: dispersed, r: rare; D (dominance): s:
dominant, n: non-dominant.

TABLE II
SHANNON-WIENER'S DIVERSITY INDEX, (VARIANCE), AND NUMBER
OF NON-TARGET PEST SPECIES AND NATURAL ENEMIES PRESENT
IN THE BT- AND NON-BT COTTON ENVIRONMENTS

                Bt cotton (1)     Non-Bt cotton (1)
Whole plant        (n=272)             (n=272)        t-Student     P

Non-target    2.11(0.004)(25) a   2.04(0.005)(27) b     1.98      0.047
  pests
Natural        2.17(0.002X24)      2.21(0.001)(22)     -0.558     0.576
  enemies

                Bt cotton (1)     Non-Bt cotton (1)
Beat sheet         (n=128)             (n=128)        t-Student     P

Non-target     2.32(0.001)(20)     2.23(0.001)(22)      1.643     0.100
  pests
Natural        2.04(0.002)(18)     2.12(0.002)(16)     -1.053     0.292
  enemies

(1) Different letters in a row represent non-significant values at
5%, assuming equal variances by Levene's test.

TABLE III
MEAN NUMBER OF ARTHROPOD SPECIMENS (SD) PER TYPE
OF COTTON AND SAMPLING METHOD

               Bt cotton (1)    Non-Bt cotton (1)   t-Student      P
Whole plant       (n=272)            (n=272)           (2)

Target pests   0.03 (0.19) a     0.35 (0.76) (b)    7.029  (3)   0.000
Non-target
  pests        10.45 (6.94) a    9.11 (6.68) (b)      2.626      0.009
Natural
  enemies       2.36 (2.67)        2.50 (2.78)        0.817      0.414

               Bt cotton (1)    Non-Bt cotton (1)   t-Student      P
Beat sheet        (n=128)            (n=128)           (2)

Target pests   0.00 (0.00) a     0.52 (0.96) (b)    6.777 (3)    0.000
Non-target
  pests         4.35 (3.09)        4.87 (4.28)      0.498 (3)    0.619
Natural
  enemies       2.50 (2.38)        2.71 (2.21)        1.209      0.228

(1) Different letters in a row represent non-significant values at 5%,
assuming equal variances by Levene's test. (2) Original data
transformed to [square root of X+0.5] for statistical analysis
purposes.

(3) Different variances.

TABLE IV
MEAN NUMBER (SD) OF INDIVIDUALS FROM DOMINANT NON-TARGET PEST
SPECIES PER TYPE OF COTTON AND SAMPLING METHOD

                                    Bt-cotton (3)   Non-Bt cotton (3)
Whole plant               Stage 2      (n=272)           (n=272)

Horciasoides nobilellus     Ad      2.25 (3.28)       2.02 (3.29)
Anthonomus grandis          Ad      0.86 (1.62) a     0.57 (1.19) b
Agallia albidula            Ad      1.16 (1.47)       0.96 (1.33)
Nezara viridula              N      0.06 (0.25)       0.03 (0.17)
Nezara viridula             Ad      0.17 (0.59)       0.19 (0.56)
Euschistus heros             N      0.04 (0.23)       0.03 (0.19)
Euschistus heros            Ad      0.38 (0.84)       0.31 (0.95)
Edessa meditabunda           N      0.04 (0.38)       0.03 (0.20)
Edessa meditabunda          Ad      0.43 (1.08) a     0.24 (0.73) b
Dysdercus sp.                N      0.06 (0.27)       0.07 (0.38)
Dysdercus sp.               Ad      0.74 (1.41)       0.73 (1.33)
Diabrotica speciosa         Ad      0.19 (0.47)       0.17 (0.45)

Whole plant               t-Student (1)     P

Horciasoides nobilellus       0.848       0.397
Anthonomus grandis            2.267       0.024
Agallia albidula              1.703       0.089
Nezara viridula               1.345       0.179
Nezara viridula               0.594       0.553
Euschistus heros              0.787       0.431
Euschistus heros              1.017       0.309
Edessa meditabunda            0.319       0.750
Edessa meditabunda            2.451       0.015
Dysdercus sp.                 0.316       0.752
Dysdercus sp.                 0.121       0.903
Diabrotica speciosa           0.679       0.498

                                    Bt-cotton (3)   Non-Bt cotton (3)
Beat sheet                Stage 2      (n=128)           (n=128)

Horciasoides nobilellus     Ad       1.11 (1.43)       1.17 (1.52)
Anthonomus grandis          Ad       0.37 (0.79)       0.35 (0.78)
Agallia albidula            Ad       0.09 (0.28)       0.09 (0.50)
Nezara viridula              N       0.08 (0.29)       0.06 (0.27)
Nezara viridula             Ad       0.23 (0.55)       0.18 (0.46)
Euschistus heros             N       0.00 (0.00)       0.02 (0.12)
Euschistus heros            Ad       0.31 (0.64)       0.23 (0.53)
Edessa meditabunda           N       0.01 (0.08)       0.00 (0.00)
Edessa meditabunda          Ad       0.47 (1.37)       0.59 (1.97)
Dysdercus sp.                N       0.02 (0.15)       0.06 (0.62)
Dysdercus sp.               Ad       0.75 (1.23)       1.23 (2.03)
Diabrotica speciosa         Ad       0.27 (0.64)       0.20 (0.49)

Beat sheet                t-Student (1)     P

Horciasoides nobilellus       0.250       0.803
Anthonomus grandis            0.209       0.834
Agallia albidula              0.219       0.827
Nezara viridula               0.463       0.644
Nezara viridula               0.812       0.418
Euschistus heros              1.420       0.157
Euschistus heros              1.111       0.268
Edessa meditabunda            1.000       0.318
Edessa meditabunda            0.241       0.810
Dysdercus sp.                 0.438       0.662
Dysdercus sp.                 1.821       0.070
Diabrotica speciosa           0.859       0.391

(1) Original data transformed to [square root of X+0.5] for
statistical analysis purposes. (2) N: nymph, Ad: adult. (3) Different
letters in a row represent non-significant values at 5%, assuming
equal variances by Levene's test.

TABLE V
MEAN NUMBER OF SPECIMENS (SD) OF INDIVIDUALS FROM DOMINANT NATURAL
ENEMY SPECIES PER TYPE OF COTTON AND SAMPLING METHOD

                                   Bt-cotton    Non-Bt cotton
Whole plant           Stage (2)     (n=272)        (n=272)

Cycloneda sanguinea       L       0.20 (0.58)    0.21 (0.82)
Cycloneda sanguinea      Ad       0.07 (0.31)    0.07 (0.29)
Scymnus sp.               L       0.56 (1.29)    0.46 (1.15)
Scymnus sp.              Ad       0.15 (0.41)    0.18 (0.58)
Chrysoperla sp.           L       0.10 (0.51)    0.08 (0.28)
Geocoris sp.             Ad       0.15 (0.44)    0.19 (0.53)
Orius sp.                Ad       0.10 (0.45)    0.17 (0.62)
Araneae                  Ad       0.56 (0.93)    0.68 (1.00)
Catolaccus grandis        L       0.14 (0.62)    0.12 (0.64)

Whole plant           t-Student (1)     P

Cycloneda sanguinea       0.231       0.817
Cycloneda sanguinea       0.235       0.815
Scymnus sp.               0.771       0.441
Scymnus sp.               0.425       0.671
Chrysoperla sp.           0.332       0.740
Geocoris sp.              0.951       0.342
Orius sp.                 1.326       0.185
Araneae                   1.629       0.104
Catolaccus grandis        0.533       0.594

                                   Bt-cotton    Non-Bt cotton
Beat sheet            Stage (2)     (n=128)        (n=128)

Cycloneda sanguinea       L       0.27 (0.70)    0.27 (1.09)
Cycloneda sanguinea      Ad       0.07 (0.31)    0.08 (0.26)
Scymnus sp.               L       0.61 (1.13)    0.56 (0.91)
Scymnus sp.              Ad       0.11 (0.36)    0.08 (0.26)
Chrysoperla sp.           L       0.20 (0.71)    0.16 (0.38)
Geocoris sp.             Ad       0.16 (0.40)    0.22 (0.46)
Orius sp.                Ad       0.18 (0.63)    0.32 (0.84)
Araneae                  Ad       0.45 (0.85)    0.56 (0.81)
Catolaccus grandis        L       0.29 (0.88)    0.25 (0.93)

Beat sheet            t-Student (1)     P

Cycloneda sanguinea       0.577       0.564
Cycloneda sanguinea       0.367       0.714
Scymnus sp.               0.063       0.950
Scymnus sp.               0.694       0.489
Chrysoperla sp.           0.258       0.797
Geocoris sp.              1.160       0.247
Orius sp.                 1.518       0.130
Araneae                   1.343       0.180
Catolaccus grandis        0.546       0.585

(1) Original data transformed to [square root of X+0.5] for
statistical analysis purposes. (2) L: larva, Ad: adult.
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Title Annotation:REPORTS/COMUNICACIONES/COMUNICACOES
Author:Thomazoni, Danielle; Soria, Miguel Ferreira; Degrande, Paulo Eduardo; Faccenda, Odival; Silvie, Pier
Publication:Interciencia
Date:Dec 1, 2013
Words:8437
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