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Transgenic Bacillus thuringiensis (Bt) rice is safer to aquatic ecosystems than its non-transgenic counterpart.

Li G, Wang Y, Liu B, Zhang G - PLoS ONE (2014)

Bottom Line: Field investigations showed that rice type (Bt and non-Bt) significantly influenced zooplankton abundance and diversity, which were up to 95% and 80% lower in non-Bt rice fields than Bt rice fields.Laboratory rearing showed that water from non-Bt rice fields was significantly less suitable for the survival and reproduction of Daphnia magna and Paramecium caudatum in comparison with water from Bt rice fields.Our results demonstrate that Bt rice is safer to aquatic ecosystems than non-Bt rice, and its commercialization will be beneficial for biodiversity restoration in rice-based ecosystems.

View Article: PubMed Central - PubMed

Affiliation: Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, P.R. CHINA.

ABSTRACT
Rice lines genetically modified with the crystal toxin genes from Bacillus thuringiensis (Bt) have experienced rapid development, with biosafety certificates for two Bt rice lines issued in 2009. There has still been no commercial release of these lines yet due to public concerns about human health and environmental risks. Some studies confirmed that Bt rice was as safe as conventional rice to non-target organisms when pesticides were not applied, however, pesticides are still required in Bt rice to control non-lepidopteran pests. In this study, we assessed the environmental effects of two Bt rice lines expressing either the cry1Ab/1Ac or cry2A genes, respectively, by using zooplanktons as indicator species under normal field management practices using pesticides when required. In the whole rice growing season, non-Bt rice was sprayed 5 times while Bt rice was sprayed 2 times, which ensured both rice achieved a normal yield. Field investigations showed that rice type (Bt and non-Bt) significantly influenced zooplankton abundance and diversity, which were up to 95% and 80% lower in non-Bt rice fields than Bt rice fields. Laboratory rearing showed that water from non-Bt rice fields was significantly less suitable for the survival and reproduction of Daphnia magna and Paramecium caudatum in comparison with water from Bt rice fields. Higher pesticide residues were detected in the water from non-Bt than Bt rice fields, accounting for the bad performance of zooplankton in non-Bt field water. Our results demonstrate that Bt rice is safer to aquatic ecosystems than non-Bt rice, and its commercialization will be beneficial for biodiversity restoration in rice-based ecosystems.

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Related in: MedlinePlus

Population growth of P. caudatum in culture medium made of field water.Field water was collected from non-Bt rice and Bt rice plots 11 days after the final pesticide spray (see Table S1). Error bars indicate the standard error.
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pone-0104270-g003: Population growth of P. caudatum in culture medium made of field water.Field water was collected from non-Bt rice and Bt rice plots 11 days after the final pesticide spray (see Table S1). Error bars indicate the standard error.

Mentions: A stock of P. caudatum was cultured in the laboratory by traditional methods [29]. The stock culture was diluted to 54.3 cells ml−1 in 50 ml culture medium with 10 ml rice straw infusion and approx. 37 ml filtered field water collected from Bt and non-Bt plots. The population growth was inspected daily until the 8th day. The P. caudatum expressed lower growth rate in non-Bt rice compared to the two Bt rice treatments (Fig. 3). Repeated-measures ANOVA within RCBD detected significant effects of rice type (d.f. = 2,4; F = 195.707; p<0.001), measuring time (d.f. = 8,32; F = 1790.116; p<0.001) and the interaction of rice type×measuring time (d.f. = 16,32; F = 13.109; p<0.001). The growth rates did not differ between Bt rice 1 and Bt rice 2 (LSD test, p = 0.072). The mean density was about 300 cells/ml in non- Bt culture, and 450 and 500 in Bt rice 1 and Bt rice 2 cultures by the end of this experiment.


Transgenic Bacillus thuringiensis (Bt) rice is safer to aquatic ecosystems than its non-transgenic counterpart.

Li G, Wang Y, Liu B, Zhang G - PLoS ONE (2014)

Population growth of P. caudatum in culture medium made of field water.Field water was collected from non-Bt rice and Bt rice plots 11 days after the final pesticide spray (see Table S1). Error bars indicate the standard error.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4126711&req=5

pone-0104270-g003: Population growth of P. caudatum in culture medium made of field water.Field water was collected from non-Bt rice and Bt rice plots 11 days after the final pesticide spray (see Table S1). Error bars indicate the standard error.
Mentions: A stock of P. caudatum was cultured in the laboratory by traditional methods [29]. The stock culture was diluted to 54.3 cells ml−1 in 50 ml culture medium with 10 ml rice straw infusion and approx. 37 ml filtered field water collected from Bt and non-Bt plots. The population growth was inspected daily until the 8th day. The P. caudatum expressed lower growth rate in non-Bt rice compared to the two Bt rice treatments (Fig. 3). Repeated-measures ANOVA within RCBD detected significant effects of rice type (d.f. = 2,4; F = 195.707; p<0.001), measuring time (d.f. = 8,32; F = 1790.116; p<0.001) and the interaction of rice type×measuring time (d.f. = 16,32; F = 13.109; p<0.001). The growth rates did not differ between Bt rice 1 and Bt rice 2 (LSD test, p = 0.072). The mean density was about 300 cells/ml in non- Bt culture, and 450 and 500 in Bt rice 1 and Bt rice 2 cultures by the end of this experiment.

Bottom Line: Field investigations showed that rice type (Bt and non-Bt) significantly influenced zooplankton abundance and diversity, which were up to 95% and 80% lower in non-Bt rice fields than Bt rice fields.Laboratory rearing showed that water from non-Bt rice fields was significantly less suitable for the survival and reproduction of Daphnia magna and Paramecium caudatum in comparison with water from Bt rice fields.Our results demonstrate that Bt rice is safer to aquatic ecosystems than non-Bt rice, and its commercialization will be beneficial for biodiversity restoration in rice-based ecosystems.

View Article: PubMed Central - PubMed

Affiliation: Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, P.R. CHINA.

ABSTRACT
Rice lines genetically modified with the crystal toxin genes from Bacillus thuringiensis (Bt) have experienced rapid development, with biosafety certificates for two Bt rice lines issued in 2009. There has still been no commercial release of these lines yet due to public concerns about human health and environmental risks. Some studies confirmed that Bt rice was as safe as conventional rice to non-target organisms when pesticides were not applied, however, pesticides are still required in Bt rice to control non-lepidopteran pests. In this study, we assessed the environmental effects of two Bt rice lines expressing either the cry1Ab/1Ac or cry2A genes, respectively, by using zooplanktons as indicator species under normal field management practices using pesticides when required. In the whole rice growing season, non-Bt rice was sprayed 5 times while Bt rice was sprayed 2 times, which ensured both rice achieved a normal yield. Field investigations showed that rice type (Bt and non-Bt) significantly influenced zooplankton abundance and diversity, which were up to 95% and 80% lower in non-Bt rice fields than Bt rice fields. Laboratory rearing showed that water from non-Bt rice fields was significantly less suitable for the survival and reproduction of Daphnia magna and Paramecium caudatum in comparison with water from Bt rice fields. Higher pesticide residues were detected in the water from non-Bt than Bt rice fields, accounting for the bad performance of zooplankton in non-Bt field water. Our results demonstrate that Bt rice is safer to aquatic ecosystems than non-Bt rice, and its commercialization will be beneficial for biodiversity restoration in rice-based ecosystems.

Show MeSH
Related in: MedlinePlus