CitrusVol Validation for the Adjustment of Spray Volume in Treatments against Tetranychus urticae in Clementines
Round 1
Reviewer 1 Report
The article present work on the effect of pesticide reduction on treatment against spider mite.
I find the work interesting but the results could have been compared to results from other researchers. It is a tool developed the authors and compared with own results.
I question that some of the results on the coverage % increase with decreasing amount of water. It might have something to do with the spray itself. some comment should be added.
I am not working on this field of research myself, but the wind speed on the day of spraying should be an interesting parameter to have in the combination with coverage.
Author Response
Dear Reviewer 1
We are grateful for your suggestions that will contribute to improve the manuscript. We provide a point-by-point response to each comment:
The article present work on the effect of pesticide reduction on treatment against spider mite.
I find the work interesting but the results could have been compared to results from other researchers. It is a tool developed the authors and compared with own results.
We have included the comparison of the results with works of other authors in the discussion.
I question that some of the results on the coverage % increase with decreasing amount of water. It might have something to do with the spray itself. some comment should be added.
The coverage decreased or was similar for VA respect to VC in virtually all cases. It was just in one case, in one area of the canopy and in one plot (P7), in one treatment from 2017, where significantly higher percentage of coverage was achieved with VC than with VA. In this plot the lowest water reduction was achieved with the tool. We considered this as a fruit of chance and it should not be highlighted in the manuscript.
I am not working on this field of research myself, but the wind speed on the day of spraying should be an interesting parameter to have in the combination with coverage.
Meteorological data during all the applications were included in the Appendix A, Table A1
Best regards
Reviewer 2 Report
I was excited when I read the title and abstract and pleased to review this manuscript. It is very important to both show and assure growers appropriate ways to maximize use of PPP. This paper clearly shows that a grower can reduce the volume of spray and rates used to control pest. I agree that it will reduce spray drift and overall amounts of pesticide being used. That is the overwhelming value of this paper. I had a few concerns scientifically. While the growers do indeed use a variety of equipment and treatments. I think it may have bore out some of the treatment differences if some of these variables were controlled. For example, the products used were different in nearly every application. In one case abamectin was considered the main active ingredient for two-spotted spider mite control and in another application, it was included but not considered the main active ingredient for two-spotted spider mite control. If the same treatments were used for each application, then I think the data may have been more robust and possibly more differences would have appeared in some of the statistical analysis. Use of the same spray equipment and spray pressures across all applications may have also made the data more homogeneous to accent the spray volume differences. Nevertheless, the data do strongly support that lower spray volumes and PPP rates did not affect control of the pest. I also see the value of doing “on farm” experiments and I commend you for that work.
Author Response
Dear Reviewer 2,
We are grateful for your suggestions that will contribute to improve the manuscript. We provide a point-by-point response to each comment:
I was excited when I read the title and abstract and pleased to review this manuscript. It is very important to both show and assure growers appropriate ways to maximize use of PPP. This paper clearly shows that a grower can reduce the volume of spray and rates used to control pest. I agree that it will reduce spray drift and overall amounts of pesticide being used. That is the overwhelming value of this paper. I had a few concerns scientifically. While the growers do indeed use a variety of equipment and treatments. I think it may have bore out some of the treatment differences if some of these variables were controlled. For example, the products used were different in nearly every application. In one case abamectin was considered the main active ingredient for two-spotted spider mite control and in another application, it was included but not considered the main active ingredient for two-spotted spider mite control. If the same treatments were used for each application, then I think the data may have been more robust and possibly more differences would have appeared in some of the statistical analysis. Use of the same spray equipment and spray pressures across all applications may have also made the data more homogeneous to accent the spray volume differences. Nevertheless, the data do strongly support that lower spray volumes and PPP rates did not affect control of the pest. I also see the value of doing “on farm” experiments and I commend you for that work.
The aim of the study was not to validate the tool in a certain controlled field conditions, but it was to validate the tool in real conditions, that is, know what would happen if it was used by farmers. This meant that they would use the equipment they have and the products they choose, that is the reason why the same equipment or the same active ingredients were not used in all the cases. And this way, the tool is validated for any condition of use, not just for perfectly controlled conditions. One could say that if in these real conditions the tool was validated, it means that it is robust enough, but if you validate the tool in highly controlled conditions, you cannot say if it would work in real farm conditions, for which it is intended to be used.
Best regards
