title: Simultaneous expression of regulatory genes associated with specific drought-adaptive traits improves drought adaptation in peanut.
abstract: Adaptation of crops to drought-prone rain-fed conditions can be achieved by improving plant traits such as efficient water mining (by superior root characters) and cellular-level tolerance mechanisms. Pyramiding these drought-adaptive traits by simultaneous expression of genes regulating drought-adaptive mechanisms has phenomenal relevance in improving stress tolerance. In this study, we provide evidence that peanut transgenic plants expressing Alfalfa zinc finger 1 (Alfin1), a root growth-associated transcription factor gene, Pennisetum glaucum heat-shock factor (PgHSF4) and Pea DNA helicase (PDH45) involved in protein turnover and protection showed improved tolerance, higher growth and productivity under drought stress conditions. Stable integration of all the transgenes was noticed in transgenic lines. The transgenic lines showed higher root growth, cooler crop canopy air temperature difference (less CCATD) and higher relative water content (RWC) under drought stress. Low proline levels in transgenic lines substantiate the maintenance of higher water status. The survival and recovery of transgenic lines was significantly higher under gradual moisture stress conditions with higher biomass. Transgenic lines also showed significant tolerance to ethrel-induced senescence and methyl viologen-induced oxidative stress. Several stress-responsive genes such as heat-shock proteins (HSPs), RING box protein-1 (RBX1), Aldose reductase, late embryogenesis abundant-5 (LEA5) and proline-rich protein-2 (PRP2), a gene involved in root growth, showed enhanced expression under stress in transgenic lines. Thus, the simultaneous expression of regulatory genes contributing for drought-adaptive traits can improve crop adaptation and productivity under water-limited conditions.
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Vemanna S
authors.initials: VS
authors.lastname: Ramu
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Thavarekere N
authors.initials: TN
authors.lastname: Swetha
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Shekarappa H
authors.initials: SH
authors.lastname: Sheela
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Chandrashekar K
authors.initials: CK
authors.lastname: Babitha
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.|National Research Centre for Plant Biotechnology, New Delhi, India.
authors.forename: Sreevathsa
authors.initials: S
authors.lastname: Rohini
authors.affiliation: International Centre for Genetic Engineering and Biotechnology, New Delhi, India.
authors.forename: Malireddy K
authors.initials: MK
authors.lastname: Reddy
authors.affiliation: International Centre for Genetic Engineering and Biotechnology, New Delhi, India.
authors.forename: Narendra
authors.initials: N
authors.lastname: Tuteja
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Chandrashekar P
authors.initials: CP
authors.lastname: Reddy
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Trichi Ganesh
authors.initials: TG
authors.lastname: Prasad
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, India.
authors.forename: Makarla
authors.initials: M
authors.lastname: Udayakumar
mesh_terms: D000064:Acclimatization / Q000187:drug effects / Q000235:genetics*; D010367:Arachis / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*; D000069599:Crop Production / Q000379:methods; D055864:Droughts; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D005809:Genes, Regulator; D006813:Humidity; D007612:Kanamycin / Q000494:pharmacology; D009943:Organophosphorus Compounds / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D010269:Paraquat / Q000494:pharmacology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development; D030821:Plants, Genetically Modified; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D013696:Temperature; D014170:Transformation, Genetic / Q000187:drug effects
chemical_list: D009943:Organophosphorus Compounds; D010940:Plant Proteins; D007612:Kanamycin; D010269:Paraquat; C005073:ethephon
keywords: abiotic stress; canopy temperature; drought; peanut; roots; transcription factors