Compositional differences in hybrids between protoporphyrinogen IX oxidase (PPO)-inhibiting herbicide-resistant transgenic rice and weedy rice accessions

We characterized the metabolites in grains of transgenic protoporphyrinogen IX oxidase-inhibiting herbicide-resistant rice and weedy accessions using GC-MS and examined whether the chemical composition of their hybrids differed from that of the parents. We found that the metabolite profiles of transgenic rice and weedy rice were clearly separated. Although the metabolite profiles of F-2 progeny were partially separated from their parents, zygosity did not affect the profiles. The F-2 progeny had similar or intermediate levels of most major nutritional components compared with their parents. However, levels of galactopyranose, trehalose, xylofuranose, mannitol, and benzoic acid were higher in the F-2 progeny. Some fatty acids and organic acids also showed prominent quantitative differences between the F-2 progeny and the parents. Changes in the metabolite levels of transgenic crop-weed hybrids compared to their parents might influence not only the ecological consequences of the hybrids, but also the nutritional quality and food safety.

Automated summary

The metabolite profiles of transgenic rice and weedy rice were distinct, while F-2 progeny showed partial separation from their parents with unaffected zygosity. F-2 progeny had similar or intermediate levels of most major nutritional components compared to their parents, but showed higher levels of certain metabolites. Changes in metabolite levels of transgenic crop-weed hybrids compared to parents may impact ecological consequences, nutritional quality, and food safety.