Transgenic soybean overexpressing GmSAMT1 exhibits resistance to multiple-HG types of soybean cyst nematode Heterodera glycines
Jingyu Lin,Mitra Mazarei,Nan Zhao,Catherine N. Hatcher,Wegi A. Wuddineh,Mary Rudis,Timothy J. Tschaplinski,Vincent R. Pantalone,Prakash R. Arelli,Tarek Hewezi,Feng Cheng,Charles Neal Stewart
2016 May 23 Plant Biotechnology Journal
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 22.214.171.124 (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.
Lin, J., Mazarei, M., Zhao, N., Hatcher, C.N., Wuddineh, W.A., Rudis, M., Tschaplinski, T.J., Pantalone, V.R., Arelli, P.R., Hewezi, T., Chen, F., Stewart, C.N. Jr. (2016) Transgenic soybean overexpressing GmSAMT1 exhibits resistance to multiple-HG types of soybean cyst nematode Heterodera glycines. Plant Biotechnol. J., doi: 10.1111/pbi.12566