title: Inoculation of Soil with Plant Growth Promoting Bacteria Producing 1-Aminocyclopropane-1-Carboxylate Deaminase or Expression of the CorrespondingacdSGene in Transgenic Plants Increases Salinity Tolerance inCamelina sativa.
abstract: Camelina sativa(camelina) is an oilseed crop touted for use on marginal lands; however, it is no more tolerant of soil salinity than traditional crops, such as canola. Plant growth-promoting bacteria (PGPB) that produce 1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase) facilitate plant growth in the presence of abiotic stresses by reducing stress ethylene. Rhizospheric and endophytic PGPB and the correspondingacdS-mutants of the latter were examined for their ability to enhance tolerance to salt in camelina. Stimulation of growth and tolerance to salt was correlated with ACC deaminase production. Inoculation of soil with wild-type PGPB led to increased shoot length in the absence of salt, and increased seed production by approximately 30-50% under moderately saline conditions. The effect of ACC deaminase was further examined in transgenic camelina expressing a bacterial gene encoding ACC deaminase (acdS) under the regulation of the CaMV35Spromoter or the root-specificrolDpromoter. Lines expressingacdS, in particular those using therolDpromoter, showed less decline in root length and weight, increased seed production, better seed quality and higher levels of seed oil production under salt stress. This study clearly demonstrates the potential benefit of using either PGPB that produce ACC deaminase or transgenic plants expressing theacdSgene under the control of a root-specific promoter to facilitate plant growth, seed production and seed quality on land that is not normally suitable for the majority of crops due to high salt content.
authors.affiliation: Agriculture and Agri-Food Canada, SaskatoonSK, Canada; Department of Biotechnology, School of Agriculture, Shiraz UniversityShiraz, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Heydarian
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon SK, Canada.
authors.forename: Min
authors.initials: M
authors.lastname: Yu
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon SK, Canada.
authors.forename: Margaret
authors.initials: M
authors.lastname: Gruber
authors.affiliation: Department of Biology, University of Waterloo, Waterloo ON, Canada.
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Glick
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon SK, Canada.
authors.forename: Rong
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Agriculture and Agri-Food Canada, SaskatoonSK, Canada; Department of Food and Bioproduct Sciences, University of Saskatchewan, SaskatoonSK, Canada.
authors.forename: Dwayne D
authors.initials: DD
authors.lastname: Hegedus
keywords: 1-aminocyclopropane-1-carboxylate deaminase; Camelina sativa; plant growth promoting bacteria; salinity tolerance; transgenic plants