title: Transgenic soybean overexpressing GmSAMT1 exhibits resistance to multiple-HG types of soybean cyst nematode Heterodera glycines.
abstract: Soybean (Glycine max (L.) Merr.) salicylic acid methyl transferase (GmSAMT1) catalyses the conversion of salicylic acid to methyl salicylate. Prior results showed that when GmSAMT1 was overexpressed in transgenic soybean hairy roots, resistance is conferred against soybean cyst nematode (SCN), Heterodera glycines Ichinohe. In this study, we produced transgenic soybean overexpressing GmSAMT1 and characterized their response to various SCN races. Transgenic plants conferred a significant reduction in the development of SCN HG type 1.2.5.7 (race 2), HG type 0 (race 3) and HG type 2.5.7 (race 5). Among transgenic lines, GmSAMT1 expression in roots was positively associated with SCN resistance. In some transgenic lines, there was a significant decrease in salicylic acid titer relative to control plants. No significant seed yield differences were observed between transgenics and control soybean plants grown in one greenhouse with 22 °C day/night temperature, whereas transgenic soybean had higher yield than controls grown a warmer greenhouse (27 °C day/23 °C night) temperature. In a 1-year field experiment in Knoxville, TN, there was no significant difference in seed yield between the transgenic and nontransgenic soybean under conditions with negligible SCN infection. We hypothesize that GmSAMT1 expression affects salicylic acid biosynthesis, which, in turn, attenuates SCN development, without negative consequences to soybean yield or other morphological traits. Thus, we conclude that GmSAMT1 overexpression confers broad resistance to multiple SCN races, which would be potentially applicable to commercial production.
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Lin
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Mitra
authors.initials: M
authors.lastname: Mazarei
authors.affiliation: Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhao
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Catherine N
authors.initials: CN
authors.lastname: Hatcher
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Wegi A
authors.initials: WA
authors.lastname: Wuddineh
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Rudis
authors.affiliation: Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Tschaplinski
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Vincent R
authors.initials: VR
authors.lastname: Pantalone
authors.affiliation: Crop Genetics Research Unit, USDA-ARS, Jackson, TN, USA.
authors.forename: Prakash R
authors.initials: PR
authors.lastname: Arelli
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Tarek
authors.initials: T
authors.lastname: Hewezi
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.affiliation: Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA. nealstewart@utk.edu.
authors.forename: Charles Neal
authors.initials: CN
authors.lastname: Stewart
mesh_terms: D000818:Animals; D060467:Disease Resistance / Q000235:genetics; D010935:Plant Diseases / Q000235:genetics / Q000469:parasitology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000378:metabolism / Q000469:parasitology*; D040641:Quantitative Trait Loci; D020156:Salicylic Acid / Q000378:metabolism; D013025:Glycine max / Q000235:genetics* / Q000378:metabolism / Q000469:parasitology*; D014431:Tylenchoidea / Q000502:physiology*
chemical_list: D010940:Plant Proteins; D020156:Salicylic Acid
keywords: female index; gene expression; metabolite; salicylic acid methyltransferase; soybean cyst nematode; transgenic soybean; yield