Alok Das1, Partha Sarathi Basu2, Manoj Kumar3, Jamal Ansari3, Alok Shukla3, Shallu Thakur3, Parul Singh2, Subhojit Datta3, Sushil Kumar Chaturvedi4, M S Sheshshayee5, Kailash Chandra Bansal6, Narendra Pratap Singh3. 1. Division of Plant Biotechnology, ICAR-Indian Institute of Pulses Research, Kanpur, 208 024, India. alok.das@icar.gov.in. 2. Division of Basic Sciences, ICAR-Indian Institute of Pulses Research, Kanpur, 208 024, India. 3. Division of Plant Biotechnology, ICAR-Indian Institute of Pulses Research, Kanpur, 208 024, India. 4. Division of Crop Improvement, ICAR-Indian Institute of Pulses Research, Kanpur, 208 024, India. 5. Department of Crop Physiology, University of Agricultural Sciences, GKVK Campus, Bangalore, 560 065, India. 6. ICAR-National Institute of Plant Biotechnology, New Delhi, 110 012, India.
Abstract
BACKGROUND: Chickpea (Cicer arietinum L.) is the second most widely grown pulse and drought (limiting water) is one of the major constraints leading to about 40-50% yield losses annually. Dehydration responsive element binding proteins (DREBs) are important plant transcription factors that regulate the expression of many stress-inducible genes and play a critical role in improving the abiotic stress tolerance. Transgenic chickpea lines harbouring transcription factor, Dehydration Responsive Element-Binding protein 1A from Arabidopsis thaliana (AtDREB1a gene) driven by stress inducible promoter rd29a were developed, with the intent of enhancing drought tolerance in chickpea. Performance of the progenies of one transgenic event and control were assessed based on key physiological traits imparting drought tolerance such as plant water relation characteristics, chlorophyll retention, photosynthesis, membrane stability and water use efficiency under water stressed conditions. RESULTS: Four transgenic chickpea lines harbouring stress inducible AtDREB1a were generated with transformation efficiency of 0.1%. The integration, transmission and regulated expression were confirmed by Polymerase Chain Reaction (PCR), Southern Blot hybridization and Reverse Transcriptase polymerase chain reaction (RT-PCR), respectively. Transgenic chickpea lines exhibited higher relative water content, longer chlorophyll retention capacity and higher osmotic adjustment under severe drought stress (stress level 4), as compared to control. The enhanced drought tolerance in transgenic chickpea lines were also manifested by undeterred photosynthesis involving enhanced quantum yield of PSII, electron transport rate at saturated irradiance levels and maintaining higher relative water content in leaves under relatively severe soil water deficit. Further, lower values of carbon isotope discrimination in some transgenic chickpea lines indicated higher water use efficiency. Transgenic chickpea lines exhibiting better OA resulted in higher seed yield, with progressive increase in water stress, as compared to control. CONCLUSIONS: Based on precise phenotyping, involving non-invasive chlorophyll fluorescence imaging, carbon isotope discrimination, osmotic adjustment, higher chlorophyll retention and membrane stability index, it can be concluded that AtDREB1a transgenic chickpea lines were better adapted to water deficit by modifying important physiological traits. The selected transgenic chickpea event would be a valuable resource that can be used in pre-breeding or directly in varietal development programs for enhanced drought tolerance under parched conditions.
BACKGROUND:Chickpea (Cicer arietinum L.) is the second most widely grown pulse and drought (limiting water) is one of the major constraints leading to about 40-50% yield losses annually. Dehydration responsive element binding proteins (DREBs) are important plant transcription factors that regulate the expression of many stress-inducible genes and play a critical role in improving the abiotic stress tolerance. Transgenic chickpea lines harbouring transcription factor, Dehydration Responsive Element-Binding protein 1A from Arabidopsis thaliana (AtDREB1a gene) driven by stress inducible promoter rd29a were developed, with the intent of enhancing drought tolerance in chickpea. Performance of the progenies of one transgenic event and control were assessed based on key physiological traits imparting drought tolerance such as plant water relation characteristics, chlorophyll retention, photosynthesis, membrane stability and water use efficiency under water stressed conditions. RESULTS: Four transgenic chickpea lines harbouring stress inducible AtDREB1a were generated with transformation efficiency of 0.1%. The integration, transmission and regulated expression were confirmed by Polymerase Chain Reaction (PCR), Southern Blot hybridization and Reverse Transcriptase polymerase chain reaction (RT-PCR), respectively. Transgenic chickpea lines exhibited higher relative water content, longer chlorophyll retention capacity and higher osmotic adjustment under severe drought stress (stress level 4), as compared to control. The enhanced drought tolerance in transgenic chickpea lines were also manifested by undeterred photosynthesis involving enhanced quantum yield of PSII, electron transport rate at saturated irradiance levels and maintaining higher relative water content in leaves under relatively severe soil water deficit. Further, lower values of carbon isotope discrimination in some transgenic chickpea lines indicated higher water use efficiency. Transgenic chickpea lines exhibiting better OA resulted in higher seed yield, with progressive increase in waterstress, as compared to control. CONCLUSIONS: Based on precise phenotyping, involving non-invasive chlorophyll fluorescence imaging, carbon isotope discrimination, osmotic adjustment, higher chlorophyll retention and membrane stability index, it can be concluded that AtDREB1a transgenic chickpea lines were better adapted to water deficit by modifying important physiological traits. The selected transgenic chickpea event would be a valuable resource that can be used in pre-breeding or directly in varietal development programs for enhanced drought tolerance under parched conditions.
Authors: M Holsters; B Silva; F Van Vliet; C Genetello; M De Block; P Dhaese; A Depicker; D Inzé; G Engler; R Villarroel Journal: Plasmid Date: 1980-03 Impact factor: 3.466
Authors: G Ravikumar; P Manimaran; S R Voleti; D Subrahmanyam; R M Sundaram; K C Bansal; B C Viraktamath; S M Balachandran Journal: Transgenic Res Date: 2014-01-08 Impact factor: 2.788
Authors: Alessandro Pellegrineschi; Matthew Reynolds; Mario Pacheco; Rosa Maria Brito; Rosaura Almeraya; Kazuko Yamaguchi-Shinozaki; David Hoisington Journal: Genome Date: 2004-06 Impact factor: 2.166
Authors: Rajeev K Varshney; Chi Song; Rachit K Saxena; Sarwar Azam; Sheng Yu; Andrew G Sharpe; Steven Cannon; Jongmin Baek; Benjamin D Rosen; Bunyamin Tar'an; Teresa Millan; Xudong Zhang; Larissa D Ramsay; Aiko Iwata; Ying Wang; William Nelson; Andrew D Farmer; Pooran M Gaur; Carol Soderlund; R Varma Penmetsa; Chunyan Xu; Arvind K Bharti; Weiming He; Peter Winter; Shancen Zhao; James K Hane; Noelia Carrasquilla-Garcia; Janet A Condie; Hari D Upadhyaya; Ming-Cheng Luo; Mahendar Thudi; C L L Gowda; Narendra P Singh; Judith Lichtenzveig; Krishna K Gali; Josefa Rubio; N Nadarajan; Jaroslav Dolezel; Kailash C Bansal; Xun Xu; David Edwards; Gengyun Zhang; Guenter Kahl; Juan Gil; Karam B Singh; Swapan K Datta; Scott A Jackson; Jun Wang; Douglas R Cook Journal: Nat Biotechnol Date: 2013-01-27 Impact factor: 54.908