Priming with Humic Acid to Reverse Ageing Damage in Soybean [Glycine max (L.) Merrill.] Seeds
, Uma Rani Sinniah 1,*, Parameswari Namasivayam 3, Muhamad Hazim Nazli 1, Sharif Azmi Abdurahman 1 and Mohd Norsazwan Ghazali 1Round 1
Reviewer 1 Report
This study focuses on quantification of a seed priming treatment effect for soybean seeds in order to improve the seed viability. The study not only measures the improvement in germination and plantlet vigor but also presents data on the chemical and physiological mechanisms responsible. The study in general is sound and would only need a few modifications, most of them formal:
1) In section 2.3 it is mentioned that there are laboratory and glasshouse germination experiments, but in the results there is mention of "field" restults. The terminology "glasshouse" and "laboratory" should be maintained thoughout the text to clarify which results are obtained on each experiment. Avoid the term "field" that would imply open-air and farm-like conditions which is confusing for the reader.
2) In the material and methods section there is a lot of references to many calculations such as germination rate index, velocity of germination, etc. but the formulas are not presented nor easily available for the reader. Such formulas (clearly defining all the values presented in tables and figures) should be written down and included in a Supplementary PDF file to be consulted by the reader. The original cites should be kept in the text as well.
3) In figure 3) (a) the bars have the outer lines in grey and they should be black.
4) In my opinion, the improvement of germination percentage is limited (from 62 to 71%, table 2), and I don't know if this improvement is good enough to say that the implementation of this priming system at farm level would be economically justified. The discussion section should address this question comparing the efficiency of this priming with humic acid with other possible solutions that are described in the literature with soybean or other comparable species.
5) In the discussion, lines 404-406 it says "data not mentioned in results". Please mention it in the results and eliminate this "data not mentioned in results" statement.
Author Response
Thank you very much for your valuable comments to improve the manuscript.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The germination of soybean seeds is decreased quickly during storage. The manuscript by Weerasekara et al. reports that priming aged soybean seeds with 0.2g/L HA in 5 h could improved seed establishment. This treatment could be useful to improve the germination of aged soybean seeds.
I do not have any other comments, but I have some suggestions that the author might want to follow up on, which result from questions that I had when reading the manuscript:
It was not clear to me why the authors chose 0.2g/L HA as the concentration for seed priming? Has anyone tested different HA concentration primming on soybean seeds? If yes, please add to the reference.
They show that HA priming reduces electrical conductivity and malondialdehydrate content while increases catalytic activity and peroxidase activity. However, only 5h of HA priming increases germination percentage compared to the control; but 1h, 3h, or 7h of HA priming do not. These results seem to contradict expectations and need to be further discussed.
Author Response
Thank you very much for your valuable comments to improve our manuscript.
Author Response File: Author Response.pdf
