title: Identification of drought tolerant progenies in tea by gene expression analysis.
abstract: Understanding the genes that govern tea plant (Camellia sinensis) architecture and response to drought stress is urgently needed to enhance breeding in tea with improved water use efficiency. Field drought is a slow mechanism and the plants go through an adaptive process in contrast to the drastic changes of rapid dehydration in case of controlled experiments. We identified a set of drought responsive genes under controlled condition using SSH, and validated the identified genes and their pattern of expression under field drought condition. The study was at three stages of water deficit stress viz., before wilting, wilting and recovery, which revealed a set of genes with higher expression at before wilting stage including dehydrin, abscissic acid ripening protein, glutathione peroxidase, cinnamoyl CoA reductase, calmodulin binding protein. The higher expression of these genes was related with increase tolerance character of DT/TS-463 before wilting, these five tolerant progenies could withstand drought stress and thus are candidates for breeding. We observed that physiological parameter like water use efficiency formed a close group with genes such as calmodulin related, DRM3, hexose transporter, hydrogen peroxide induced protein, ACC oxidase, lipase, ethylene responsive transcription factor and diaminopimelate decarboxylase, during wilting point. Our data provides valuable information for the gene components and the dynamics of gene expression in second and third leaf against drought stress in tea, which could be regarded as candidate targets potentially associated with drought tolerance. We propose that the identified five tolerant progenies on the basis of their drought tolerance can thus be utilised for future breeding programmes.
authors.affiliation: Department of Biotechnology, Plant Improvement Division, Tea Research Association, Tocklai, Jorhat, Assam, India.
authors.forename: Sushmita
authors.initials: S
authors.lastname: Gupta
authors.forename: Raju
authors.initials: R
authors.lastname: Bharalee
authors.forename: Priyadarshini
authors.initials: P
authors.lastname: Bhorali
authors.forename: Tirthankar
authors.initials: T
authors.lastname: Bandyopadhyay
authors.forename: Bornali
authors.initials: B
authors.lastname: Gohain
authors.forename: Niraj
authors.initials: N
authors.lastname: Agarwal
authors.forename: Parveen
authors.initials: P
authors.lastname: Ahmed
authors.forename: Hemanta
authors.initials: H
authors.lastname: Saikia
authors.forename: Sangeeta
authors.initials: S
authors.lastname: Borchetia
authors.forename: M C
authors.initials: MC
authors.lastname: Kalita
authors.forename: A K
authors.initials: AK
authors.lastname: Handique
authors.forename: Sudripta
authors.initials: S
authors.lastname: Das
mesh_terms: D000220:Adaptation, Biological; D000594:Amino Acid Oxidoreductases / Q000235:genetics / Q000378:metabolism; D028241:Camellia sinensis / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D019295:Computational Biology / Q000379:methods; D055864:Droughts; D020869:Gene Expression Profiling / Q000379:methods*; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D017343:Genes, Plant; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D008049:Lipase / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics; D018515:Plant Leaves / Q000378:metabolism / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D025341:Principal Component Analysis; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014867:Water / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors; D014867:Water; C070556:dehydrin proteins, plant; D005979:Glutathione Peroxidase; D000594:Amino Acid Oxidoreductases; C059460:1-aminocyclopropane-1-carboxylic acid oxidase; D008049:Lipase