title: Transgenic rice expressing a codon-modified synthetic CP4-EPSPS confers tolerance to broad-spectrum herbicide, glyphosate.
abstract: Highly tolerant herbicide-resistant transgenic rice was developed by expressing codon-modified synthetic CP4--EPSPS. The transformants could tolerate up to 1% commercial glyphosate and has the potential to be used for DSR (direct-seeded rice). Weed infestation is one of the major biotic stress factors that is responsible for yield loss in direct-seeded rice (DSR). Herbicide-resistant rice has potential to improve the efficiency of weed management under DSR. Hence, the popular indica rice cultivar IR64, was genetically modified using Agrobacterium-mediated transformation with a codon-optimized CP4-EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) gene, with N-terminal chloroplast targeting peptide from Petunia hybrida. Integration of the transgenes in the selected rice plants was confirmed by Southern hybridization and expression by Northern and herbicide tolerance assays. Transgenic plants showed EPSPS enzyme activity even at high concentrations of glyphosate, compared to untransformed control plants. T0, T1 and T2 lines were tested by herbicide bioassay and it was confirmed that the transgenic rice could tolerate up to 1% of commercial Roundup, which is five times more in dose used to kill weeds under field condition. All together, the transgenic rice plants developed in the present study could be used efficiently to overcome weed menace.
authors.affiliation: National Research Centre on Plant Biotechnology, Lal Bahadur Shastri Building, Pusa Campus, New Delhi, 110012, India.
authors.forename: Sushil
authors.initials: S
authors.lastname: Chhapekar
authors.forename: Sanagala
authors.initials: S
authors.lastname: Raghavendrarao
authors.forename: Gadamchetty
authors.initials: G
authors.lastname: Pavan
authors.forename: Chopperla
authors.initials: C
authors.lastname: Ramakrishna
authors.forename: Vivek Kumar
authors.initials: VK
authors.lastname: Singh
authors.forename: Mullapudi Lakshmi Venkata
authors.initials: ML
authors.lastname: Phanindra
authors.forename: Gurusamy
authors.initials: G
authors.lastname: Dhandapani
authors.forename: Rohini
authors.initials: R
authors.lastname: Sreevathsa
authors.forename: Polumetla
authors.initials: P
authors.lastname: Ananda Kumar
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase / Q000235:genetics* / Q000378:metabolism; D003062:Codon / Q000235:genetics; D004351:Drug Resistance; D015870:Gene Expression; D005818:Genetic Engineering; D005998:Glycine / Q000031:analogs & derivatives* / Q000494:pharmacology; D006540:Herbicides / Q000494:pharmacology*; D012275:Oryza / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D012639:Seeds / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D019076:Transgenes; D058728:Weed Control; D000097797:Glyphosate
chemical_list: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D003062:Codon; D005998:Glycine; D006540:Herbicides; D000097797:Glyphosate