Abstract
Genetic modifications of plants can affect their ability to use environmental resources. It is known that the anthropic action has caused global climate changes, such as increases in temperature and drought. In view of this, the objective of this study was to evaluate if the addition of the Bt gene influences the physiological performance of isogenic maize hybrids grown under water stress and optimal conditions. Three Bt and non-Bt maize hybrids (Agromen 30A95, Dow 2B707 and BG 7049Y) were cultivated in soil with moisture content at 60% (water stress) and 100% of the field capacity (FC). Among the hybrids, the 30A95 presented greater variation between Bt and non-Bt hybrids in regard to physiological variables. The addition of the Bt gene practically had no impact on the photosynthetic performance of the 2B707 and BG7049 hybrids. The presence of the Bt gene increased the sensitivity to water stress in the hybrids, with reduction of maximal fluorescence and chlorophyll content in the plants. Regardless of the genetic factor (Bt or non-Bt), water stress reduced transpiration, stomatal conductance, photosynthetic rate, and maximum quantum yield of the PSII in maize plants. It was concluded that the presence of the Bt gene in maize indicates a reduction in the photosynthetic potential of the plant grown under water stress.
Highlights
Resumo - Modificações genéticas de plantas podem afetar a capacidade das mesmas em utilizar os recursos do ambiente
Fv values were similar in the comparisons between conventional maize hybrids or between Bt hybrids cultivated under water deficit condition (60 % of field capacity (FC)) (Table 2)
On the other hand, when maize was cultivated in soil at field capacity, Fv varied between conventional hybrids and between transgenic hybrids
Summary
Resumo - Modificações genéticas de plantas podem afetar a capacidade das mesmas em utilizar os recursos do ambiente. Besides the changes expected as a result of genetic transformation, some studies identified alterations in transgenic maize plants, such as modifications in the stem diameter, leaf area, interval between male and female flowering, and antioxidant enzyme content (Rasco Jr et al, 2010). This reinforces the hypothesis that physiological and morphological changes may occur in transgenic maize plants when compared to the conventional versions. The objective of this study was to confirm if the addition of the Bt gene influences the performance of isogenic maize cultivars grown under optimal conditions and water stress
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
