Strategies for Selecting Early Maturing Maize Inbred Lines for Hybrid Production under Low Soil Nitrogen and Striga Infestation

Round 1

Reviewer 1 Report

General

This manuscript aims to identify early maturing inbred lines based on multiple-traits under optimal, low-N and Striga infested environments for hybrid development and population improvement.

The results of this study shown that days to silking, ears per plot and days to anthesis had high direct effects on grain yield under optimal growing conditions, days to silking and ears per plant had the highest positive, while days to anthesis had the highest negative direct effects on grain yield in low-N conditions.

Forty-eight of the 100 inbred lines studied were identified as low-N tolerant, and forty-nine as Striga resistant environments.

The results have certain significances on maize genetic breeding, however, there are certain areas which need to be clarified further in the manuscript such as the expression is not clear, making me wonder if I could understand it very well or not, probably, I may have poorly understood at some of the points for ambiguous statements.

 The detail comments about this paper are listed as follows. 

1. The introduction section is weakly structured. The authors should focus on why they conducted this study at this type of soil and climate condition. There are a great many of similar studies over the world, the authors must highlight the significance of this study.

2. According to the supplementary information, the grain yields of all the entries are extremely low, and the yields in low N or Striga conditions are higher than optimal environment for some entries, it is confusion, please explain and add more information in the Material part.

Author Response

Reviewers comment	Authors response
The introduction section is weakly structured. The authors should focus on why they conducted this study at this type of soil and climate condition. There are a great many of similar studies over the world, the authors must highlight the significance of this study.	The introduction section has been rewritten based on the suggestions of the reviewer.
According to the supplementary information, the grain yields of all the entries are extremely low, and the yields in low N or Striga conditions are higher than optimal environment for some entries, it is confusion, please explain and add more information in the Material part.	The unusually low yields of some entries under optimal conditions as compared to those under low-N and Striga infested environments due to errors during the compilation of Table S2 have been corrected, while those with yields under low N or Striga-infested conditions still higher than those under optimal environments have been tagged and a note attached to the tagger under the table with an explanation of the causes of such observations.
Missing table, consider using supplemental material’s for providing info about inbred lines	Information on the characteristics of the inbred lines has been provided in supplementary Table 1.

 

Reviewer 2 Report

In the MS "Strategies for Selecting Early Maturing Maize Inbred
Lines for Hybrid Production under Low Soil Nitrogen
and Striga Infestation."

the authors invetigated a collection of inbred lines with the aim of identifying the most promissing lines to be used as parents in breeding programs focussed on productivity under low soil nitrogen and striga infestation.

In my opinion, the paper is a nice piece of research with an extremely pragmatic aim: selecting lines to be used in breeding programs.

This MS sounds to me as the perfect starting point for a successful  research project. 

In my view, the MS is not adding extreme novelty to the field of research and sound like "incomplete".

I think this could be a nice starting point for a wider study, potentially covering few couples of  mapping populations maybe sharing a common parent identified in this preliminary study.

Furthermore, the high amount of genetic matherial could suggest the application of more advanced techniques, such as genome prediction.

However, I do understand the general idea of the authors of providing new basic outcomes to the community, as starting point for a more sophisticated research approach.

Overall, I think that this MS is definitely a nice preliminary study that can open the gates to a whole set of applications (QTL mapping, BSA-seq, genomic prediction).

For this reason, I evaluate this MS as good after minor revisions. Please find few comments in the attached file.

Comments for author File: Comments.pdf

Author Response

Reviewers comment	Authors response
The introduction section is weakly structured. The authors should focus on why they conducted this study at this type of soil and climate condition. There are a great many of similar studies over the world, the authors must highlight the significance of this study.	The introduction section has been rewritten based on the suggestions of the reviewer.
According to the supplementary information, the grain yields of all the entries are extremely low, and the yields in low N or Striga conditions are higher than optimal environment for some entries, it is confusion, please explain and add more information in the Material part.	The unusually low yields of some entries under optimal conditions as compared to those under low-N and Striga infested environments due to errors during the compilation of Table S2 have been corrected, while those with yields under low N or Striga-infested conditions still higher than those under optimal environments have been tagged and a note attached to the tagger under the table with an explanation of the causes of such observations.
Missing table, consider using supplemental material’s for providing info about inbred lines	Information on the characteristics of the inbred lines has been provided in supplementary Table 1.

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The revised manuscript has been improved greatly. I believe the manuscript has been sufficiently improved to warrant publication in Agronomy.

Author Response

Comments and Suggestions for Authors

The revised manuscript has been improved greatly. I believe the manuscript has been sufficiently improved to warrant publication in Agronomy.

Response

Thanks for the positive comments.