Round 1

Reviewer 1 Report

The article entitled “How seed traits can affect the performance of cover crops and what can we do to enhance it?” is an interesting review article of the literature about seed traits in cover crops. The topic is of high interest, given the high popularity of cover crops, and offers a notable novelty level. The subject of the manuscript meets the general scope of the Journal and provides key information for both farmers and scientific community. However, it shows severe gaps and weaknesses that need to be addressed. Please see the following comments and suggestions.

GENERAL COMMENTS:

·         The authors did not follow the journal’s guidelines and the template format. Please re-write and re-organize the entire manuscript accordingly.

·         Although I am not a native English, I detected a poor level of the English language. I think that the manuscript could benefit from a revision by a mother-tongue proof-reader.

·         Binomial names should be written in full (including the taxonomist) on their first appearance, and abbreviated from the second one onward

·         In several cases, updated references can be provided

SPECIFIC COMMENTS:

·         Title: I suggest not using an interrogative form. According to my experience, affirmative titles are more attractive.

·         L16-18: please explain better the aims

·         It is not necessary writing the names of botanical families in italics throughout the manuscript

·         In the abstract, the main findings may be better highlighted

·         L37-38: direct methods are not only physical, chemical, and biological

·         L45: please check the reference format

·         L37-49: this preliminary section, very common to many similar papers, may be summarised

·         L50: being the main actor of this paper, I think that cover cropping should be defined and better introduced here. If I well understand, living mulching, intercropping and dead mulching have been here intended as a part of cover cropping. To fill such gap, I invite authors integrating this recent review (https://doi.org/10.1007/s13593-022-00825-0), which can be useful for readers.

·         Reference 21 and 22 are the same. Please check all references

·         The introduction is focused only on weed control effects of cover crops, but the title refers of generic performances of cover crop. Therefore, in my opinion there are two options: setting the title for weed management purposes or changing the background of the introduction (meaning introducing the multiple ecosystem services provided by cover crops).

·         Another issue of the introduction is that seed traits have been addressed in L68-72, which is not enough in my opinion

·         Nothing is mentioned about the literature search, which is a key aspect for review articles. How it was performed? On which databases? Which keywords have been used? How many articles have been initially found? Did you apply some criteria of restriction?

·         L89-91: this sentence is not clear. Please rephrase it

·         Paragraph 2.1.1 (in particular L94-118) deals with just one article. Discussing the influence of temperature and soil moisture based on one article is not appropriate for a review.

·         There are also other abiotic factors limiting seed germination such as soil pH, active limestone and texture, but they are not discussed. Please add this information

·         Fig. 1: please highlight the bars

·         L124: please check the reference format

·         L133: has demonstrated

·         L152-153: in addition to soil organic matter and mineral nitrogen, other benefits include the enhancement of soil macro- and micro-elements, as well as the reduction of the weed soil seedbank (see https://doi.org/10.1007/s13593-021-00721-z)

·         L201: please write the genus in italics

·         L214-219: please move to paragraph 3.1.1

·         L247: please link this section with the previous one

·         L281: planting layout is more appropriate in my opinion

·         L282-285: please rephrase it

·         L359: please start with a capital letter

Please revise the manuscript with the help of a mother-tongue proof-reader.

Author Response

Reviewer#1’s comments

 

The article entitled “How seed traits can affect the performance of cover crops and what can we do to enhance it?” is an interesting review article of the literature about seed traits in cover crops. The topic is of high interest, given the high popularity of cover crops, and offers a notable novelty level. The subject of the manuscript meets the general scope of the Journal and provides key information for both farmers and scientific community. However, it shows severe gaps and weaknesses that need to be addressed. Please see the following comments and suggestions.

>>> Thanks for the comments. We addressed all the points raised here in the revised manuscript and provide a point-by-point response below.

 

 

GENERAL COMMENTS:

• The authors did not follow the journal’s guidelines and the template format. Please re-write and re-organize the entire manuscript accordingly.
• Although I am not a native English, I detected a poor level of the English language. I think that the manuscript could benefit from a revision by a mother-tongue proof-reader.

>>> We revised the whole manuscript which was first edited by a native speaker.

 

• Binomial names should be written in full (including the taxonomist) on their first appearance, and abbreviated from the second one onward

>>> we edited all species citation throughout the manuscript, as requested

 

• In several cases, updated references can be provided

>>> we cited the most updated references we knew and edited some of them as requested below

 

SPECIFIC COMMENTS:

• Title: I suggest not using an interrogative form. According to my experience, affirmative titles are more attractive.

>> we edited the title as “Knowledge on cover crop seed traits and treatments to enhance weed suppression. A review”. Adding “a review” aims to answer the reviewer’s #2 comment.

 

• L16-18: please explain better the aims

>>> we edited the sentences by :

“This study is the first one to review the scientific literature on seed traits of cover crops to identify the key biotic and abiotic factors influencing germination and early establishment (density, biomass, cover). Knowledge on seed traits would be helpful in choosing suitable cover crop species and/or mixture adapted to specific environments. Such information is crucial to improve cover crops establishment, growth, provision of ecosystem services, while allowing farmers to save seeds and therefore money. We then discuss how to improve cover crop establishment by seed priming and coating, and appropriate seed sowing pattern and depth.”

 

• It is not necessary writing the names of botanical families in italics throughout the manuscript

>> it is necessary if they are in latin. We kept them when necessary.

• In the abstract, the main findings may be better highlighted

>>> the last part of the abstract is dedicated to that purposeand we underline the key messages below.

“The review showed that seed traits related to germination are crucial as they affect the germination timing and establishment of the cover crop, consequently soil coverage uniformity, factors that directly related to their suppressive effect on weeds. Poaceae and Brassicaceae exhibit higher germination percentage than Fabaceae under water deficit conditions. Seed dormancy of some Fabaceae species/cultivars limits their agricultural use of as cover crops because the domestication of some wild ecotypes is not complete. Understanding genetic and environmental regulating seed dormancy is necessary. Appropriate selection of cover crop cultivars is crucial to improve cover crop establishment and provide multiple ecosystem services including weed suppression, particularly in a climate change context. “

 

• L37-38: direct methods are not only physical, chemical, and biological

>>> indeed. We deleted it.

 

• L45: please check the reference format

>> checked and edited. We had and issue on the reference.

 

• L37-49: this preliminary section, very common to many similar papers, may be summarised

>>> we agree. We edited the text, and some references were deleted including the one we had to change above.

 

• L50: being the main actor of this paper, I think that cover cropping should be defined and better introduced here. If I well understand, living mulching, intercropping and dead mulching have been here intended as a part of cover cropping. To fill such gap, I invite authors integrating this recent review (https://doi.org/10.1007/s13593-022-00825-0), which can be useful for readers.

>>> we better defined it by adding a definition to cover crop. And we added the reference proposed here which was appropriate.

 

• Reference 21 and 22 are the same. Please check all references

>> good catch. We edited it.

 

• The introduction is focused only on weed control effects of cover crops, but the title refers of generic performances of cover crop. Therefore, in my opinion there are two options: setting the title for weed management purposes or changing the background of the introduction (meaning introducing the multiple ecosystem services provided by cover crops).

>>> agree. We edited the title in order to highlight the focus on weed.

 

• Another issue of the introduction is that seed traits have been addressed in L68-72, which is not enough in my opinion

>>> We understand your point. But seed trait is the focus of the whole manuscript and review. We introduce the term “seed trait” in the 3^rd quarter of the introduction, then to state that it is our objective to review seed traits.

 

• Nothing is mentioned about the literature search, which is a key aspect for review articles. How it was performed? On which databases? Which keywords have been used? How many articles have been initially found? Did you apply some criteria of restriction?

>>>This is indeed required for a systematic review. Not for a narrative review as we did here. Reviews are tools that help synthesize literature on a topic of interest and describe its current state. A systematic review is one such review that is robust, reproducible, and transparent. There is a need for high-quality, focused, and precise methods and reporting. Here we provide a traditional literature reviews also sometimes referred to as narrative reviews since they use narrative analysis to synthesize data. We edited the totle to be transparent. An obviously we search for typical keywords such as cover crop, seed trait, biomass, weed suppression, etc… in Web of Science, PubMed and Google Schoolar.

 

• L89-91: this sentence is not clear. Please rephrase it

>>> Agree, done

 

• Paragraph 2.1.1 (in particular L94-118) deals with just one article. Discussing the influence of temperature and soil moisture based on one article is not appropriate for a review.

>>> When looking at the whole manuscript, we cannot say that we discuss the influence of temperature and soil moisture based on one article, since we discuss that topic multiple times. However, here, we highlighted this work since it is a fundamental, rare and recent study on cover crop species.

 

• There are also other abiotic factors limiting seed germination such as soil pH, active limestone and texture, but they are not discussed. Please add this information

>>> agree, but except pH, there is little agronomic lever to change the soil texture and we found no genetic lever to make the species more germinable in certain pH. However, as we agree, we cite now these examples in the manuscript.

 

• Fig. 1: please highlight the bars

>>> we edited the fig 1

 

• L124: please check the reference format

>>> checked and edited. Good catch.

 

• L133: has demonstrated

>>> we edited in “Previous studies have demonstrated”

 

• L152-153: in addition to soil organic matter and mineral nitrogen, other benefits include the enhancement of soil macro- and micro-elements, as well as the reduction of the weed soil seedbank (see https://doi.org/10.1007/s13593-021-00721-z)

>>> agree. We decided to add this reference which was appropriate and because the reviewer think this group from Catania (Italy) is worth being cited. This is the second reference we add from this group.

 

• L201: please write the genus in italics

>>Done

 

• L214-219: please move to paragraph 3.1.1

>>> agree. Done

 

• L247: please link this section with the previous one

>>> we deleted the sentence.

 

• L281: planting layout is more appropriate in my opinion

>> OK.

 

• L282-285: please rephrase it

>>> done

 

• L359: please start with a capital letter

>>> good catch. done

Reviewer 2 Report

A statistical evaluation of the data is needed. Without a statistical evaluation of the differences between the variants, it is not possible to recommend the manuscript for publication in a scientific journal.

 

Author Response

A statistical evaluation of the data is needed. Without a statistical evaluation of the differences between the variants, it is not possible to recommend the manuscript for publication in a scientific journal.

>>> The manuscript is a review of the literature on seed traits of cover crops, their germination response to different biotic and abiotic factors aiming to improve seed germination and seedling establishment. This was clearly stated in the abstract and the end of the introduction but we edited the last paragraph of the introduction to clearly state the objectives of the manuscript that does not requires statistical analysis.

Round 2

Reviewer 1 Report

Dear Authors,

congratulations for the review process. All my issues have been addressed. I hope I made a contribution to the improvement of the overall quality of the manuscript.

Only minor editing required.