This short review summarizes very clearly the comprehensive potential of metabolomics for the complex understanding of metabolism adapted to genetic modification or environmental stress but also for the identification of metabolic QTL in rice. Several interesting examples of responses to biotic or abiotic stress are picked to illustrate the advantage of using metabolomics for the investigation of metabolism. A detailed table summarizes almost all metabolomics studies in rice so far. Furthermore several examples were given for the potential of mQTL detection leading to the identification of unknown metabolic genes or the investigation of the genetics of metabolic stress responses. Research is clearly represented and the review will serve as an excellent overview for other researchers in the field.

For their summarizing table the authors might want to additionally consider recently published papers on metabolomics of high night temperature stress and combined heat and drought stress in rice (Glaubitz et al. 2014, Li et al. 2015).

Glaubitz U, Erban A, Kopka J, Hincha DK, Zuther E: High night temperature strongly impacts TCA cycle, amino acid and polyamine biosynthetic pathways in rice in a sensitivity dependent manner. Journal of Experiment Botany 2015, 07: DOI:10.1093/jxb/erv352

Li X, Lawas L, Malo R, Glaubitz U, Erban A, Mauleon R, Heuer S, Zuther E, Kopka J, Hincha DK, Jagadish K: Metabolic and transcriptomic signatures of rice floral organs reveal sugar starvation as a factor of reproductive failure under heat and drought, Plant, Cell and Environment 2015, 03: DOI:10.1111/pce.12545

The table might be better readable if structured into different parts as biotic and abiotic stress, genetically modified rice, grain studies, natural variability, even if there might be some overlaps between the different parts.

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The authors carefully considered all comments of the referees and structured the table as suggested. The revised manuscript was also improved by adding several new references and is now ready for publishing.

Minor changes:
P4, L24: dataset is available
P5, L10: benzoxazinone
P5, L14: delete the comma
P10, L16: approved
P13, L15: J Exp Bot 2015, 66: 6385-6397
P18, L5: Plant J 2014, 81: 160-168

Level of interest

Please indicate how interesting you found the manuscript: An article of importance in its field

Quality of written English

Please indicate the quality of language in the manuscript: Acceptable

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Please complete a declaration of competing interests, considering the following questions:
1. Have you in the past five years received reimbursements, fees, funding, or salary from an
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manuscript?

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which I do not wish to be included in my named report can be included as confidential comments
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Authors' response to review and copy editor comments: (http://www.gigasciencejournal.com/imedia/1197264894200866_comment.pdf)

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