Impact of 40 Years Use of Different Herbicide Strategies and Crop Rotations on Weed Communities in Two Sites of the Czech Republic
Round 1
Reviewer 1 Report
This research try to determine and explain changes in weed-community composition in a long-term field experiment with different crop rotations and herbicide treatments. And their hypotheses weed species diversity decreases with long-term herbicide treatment and increases in untreated controls. This study is interesting and conducting spends a long time. The main problem is how does this study control the experimental conditions over such a long period of time which is important for the results. However, the authors were not present detail information. See below for specific comments.
1. line 128
More information should be present in this table or this part, such as the area of these two sites, the history of herbicide applying before 1972.
2. lines 138-149
How does this study control of the experimental conditions over such a long period of time?
3. line 356
It is better to list all the weed species as supplementary material.
4. Correct the style of the references according to the author guideline.
Author Response
Response to Reviewer 1 Comments
Thank you very much for your review. We have tried to answer your questions and edit the article according to your suggestions.
- Line 128 - More information should be present in this table or this part, such as the area of these two sites, the history of herbicide applying before 1972.
We added some information to Table 1.
To our knowledge, no herbicides were used on the experimental site for at least 2 years before starting the trial.
- Lines 138-149 - How does this study control of the experimental conditions over such a long period of time?
Researchers and scientists in Crop Research Institute has many years of experience in conducting the long-term field trials. At the beginning of our experiment, the uniform experiment methodology was created for both experimental stations. This means that agronomical practices, herbicide application, the method of evaluating weeds, etc., were given. These stations were staffed by experts who were responsible for correct adherence to the methodology. Furthermore, compliance with the methodology was checked by the coordinator of the experiment throughout the entire period. In addition, the assessment of weeds was always carried out by one researcher – coordinator of the experiment. From the beginning of the experiment, Doc. Zemánek, after his retirement Doc. Mikulka and in recent years Dr. Mayerová.
- Line 356 - It is better to list all the weed species as supplementary material.
We added list of all weed species to supplementary material – Suppl. S1.
- Correct the style of the references according to the author guideline
We corrected References as recommended.
Reviewer 2 Report
The following points need to be carefully considered:
Title:
-In materials and methods, the experiment began in 1972 (50 years ago) instead of 40 years ago. That needs to be explained.
Abstract:
-It would be helpful if you provided more statistical results in the abstract.
-Line 16: As the auxins herbicides could control the broad-leaf weeds, what kind of herbicides used for narrow-leaf weeds in this treatment?
Introduction:
-The problems that motivated you to conduct this study should be clearly stated.
-Lines 60-86: This unnecessary information can be summarized.
Materials and Methods:
Line 125: A half-century ago? Would you mind explaining this to me?
Table 1: Physicochemical properties of soil should be included, such as pH, EC, N, P, K, etc.
Comments for author File: 
Comments.pdf
Author Response
Response to Reviewer 2 Comments
Thank you very much for your review. We have tried to answer your questions and edit the article according to your suggestions.
- Title - In materials and methods, the experiment began in 1972 (50 years ago) instead of 40 years ago. That needs to be explained.
It is true, but data collection was carried out since 1972 to 2016 (see methodology), exactly 44 years. For this reason, we chose this title. If necessary, we can change the title to: “Impact of long-term use of different…… “or “Impact of 44 years use of different…”
- Abstract - It would be helpful if you provided more statistical results in the abstract.
We edited Abstract as recommended.
- line 16: As the auxins herbicides could control the broad-leaf weeds, what kind of herbicides used for narrow-leaf weeds in this treatment?
Only synthetic auxins in cereals were used in this treatment. With the exception pea cultivation, where synthetic auxins cannot be used and PSII inhibitor or bentazone were used.
The reason was to adapt the trial design to the initial aim - found out whether repeated use of herbicides with the same mechanism of action and repeated cereals cultivation causes the spread of resistant weed species and whether this spread can be prevented by crop rotation and changing herbicides.
- Introduction - The problems that motivated you to conduct this study should be clearly stated.
We added the explanation at the end of Introduction.
- Lines 60-86: This unnecessary information can be summarized.
We have partially shortened this paragraph, but we would like to keep most of the information for the sake context. Thank you for your understanding.
- Materials and Methods:
Line 125: A half-century ago? Would you mind explaining this to me?
The long-term field trial was really established in 1972 with the aim of long-term monitoring of the herbicide application in two crop rotation systems. At the beginning of the experiment, the uniform experiment methodology was created for both experimental stations. This means that agronomical practices, herbicide application, the method of evaluating weeds, etc., were given. Compliance with the methodology was checked by the coordinator of the experiment throughout the entire period. In addition, the assessment of weeds was always carried out by one researcher – coordinator of the experiment. From the beginning of the experiment, it was Doc. Zemánek, after his retirement Doc. Mikulka and in recent years Dr. Mayerová.
Table 1: Physicochemical properties of soil should be included, such as pH, EC, N, P, K, etc.
The required information has been added to the table.
Round 2
Reviewer 1 Report
Most of the problems I mentioned have been improved
