The Efficacy of Sunn Hemp (Crotalaria juncea) and Fe₃O₄ Nanoparticles in Controlling Weed Seed Germination

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I read the manuscript and think it should be accepted for publication once some comments are addressed. See below

Line 34: Change to competition with weeds…

 

 

Lines 144-162: The way it is written it appears that there is only 1 petri-dish with one weed species per treatment (so essentially 1 replication with sampling per treatment) How many petri-dish replications did the authors have? i.e. 4 petri dishes with 50 seeds each??? Was the experiment conducted as a randomized complete block design, a completely random design etc. More detail needed here. You can’t conduct ANOVA with 1 rep.

 

Conclusion

There is nothing in the conclusion about even optimizing a greenhouse soil bioassay, much less a field study that would have application.

There is a pretty big component of the experimental design that I asked to be expanded:experimental design. This is a substantial edit.

For application to agricultural translational studies to soil microcosms experiments and eventually field studies need to be discussed. So experimental design and future applied field studies need to be discussed.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The work presented is very interesting, as it deals with the use of nanotechnology as a tool for sustainable weed management. It explores the effectiveness of sunn hemp extract, Fe₃O₄ nanoparticles and Fe₃O₄/sunn hemp nanoparticles in inhibiting the germination of three different weeds. I would like give you some suggestions to improve the paper quality:

• In the Abstract, line 19, abbreviations are used without prior explanation. Before using an abbreviation, the full term must be written out, followed by the corresponding abbreviation in parentheses.
• In the Abstract, line 25, please use subscripts correctly when referring to concentrations eg. EEC₅₀ instead of EEC50. Throughout the article, make sure that subscripts are correctly used. 
• In the Introduction, line 58, the authors state that "Sunn hemp's root, stem, and seeds are rich in dehydropyrrolizidine alkaloids" and in lines 61-62 the authors said that "Alkaloids such as riddelliine, senecionine, and seneciphylline, are known for their allelopathic effects in weed suppression". Dehydropyrrolizidine alkaloids and pyrrolizidine alkaloids have been reported to be cytotoxic and carcenogenic for mammals and humans (Stegelmeier et al, 2016; Hincks et al., 1991). I recommend to discuss this issue, because if the authors aim to develop a sustainable method for weed management, they must emphasize that the proposed approach does not involve the use of compounds that can be toxic for human health. Otherwise, this method could not be used, at least not be claimed as sustainable. 

Jeffrey R. Hincks, Hea-Young Kim, H.J. Segall, Russell J. Molyneux, Frank R. Stermitz, Roger A. Coulombe. DNA cross-linking in mammalian cells by pyrrolizidine alkaloids: Structure-activity relationships. Toxicology and Applied Pharmacology, Volume 111, Issue 1, 1991, Pages 90-98, ISSN 0041-008X,
https://doi.org/10.1016/0041-008X(91)90137-4. 

Stegelmeier BL, Colegate SM, Brown AW. Dehydropyrrolizidine Alkaloid Toxicity, Cytotoxicity, and Carcinogenicity. Toxins (Basel). 2016 Nov 29;8(12):356. doi: 10.3390/toxins8120356. PMID: 27916846; PMCID: PMC5198550.

• In the Materials and Methods section, the first time each species is mentioned, please provide its full scientific name along with the author. You can verify species names using the World Flora Online database (https://about.worldfloraonline.org/).

  The full scientific name of each species must be written the first time it appears in both the Introduction and the Materials and Methods section. For subsequent mentions, the species name should be properly abbreviated. For example, write Amaranthus retroflexus L. the first time it is mentioned in the paper and in the Materials and Methods section, and then use A. retroflexus thereafter.

• In section 2.5. Experimental desing lines 155-156 it is not clearly stated how many repetitions were prepared, neither how many Petri dishes with how many seeds each were used. It should be clarified. Additionally, this section should specify the duration of the germination experiments.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The reviewed manuscript discusses the effects of Sunn hemp aqueous extract, Fe3O4 nanoparticles, and Fe3O4/Sunn hemp nanoparticles on the germination of seeds from Chenopodium album, Sinapis arvensis, and Amaranthus retroflexus.

I find this paper well written. The introduction provides all the necessary information, and the materials and methods section is detailed. Additionally, the analyses conducted in the experiments are thorough, starting with an evaluation of the physicochemical properties of the products and exploring their ED50 and EDmax.

The results are clearly explained, and the graphs are significant and presented in good quality.

However, the discussion section requires revision. It contains results in several parts, which is not acceptable as it merely repeats the content from the Results section. The discussion should critically evaluate one's own findings in comparison to the findings of other authors, rather than reiterating the Results section.

The conclusions need to be revised as well. They address the results in detail but fail to provide a cohesive general conclusion that reflects the study's broader implications.

The literature cited is mostly valuable, drawing from reliable sources; however, it occasionally includes papers from local journals, which may raise concerns about their quality.

In line 51, please clarify what is biologically fixed by Crotalaria.

Lines 66-67 note that the three weed species listed are invasive in different regions; for instance, both *C. album* and *S. arvensis* are native to Europe. This point needs clarification.

Lines 48-49 contradict the statements made in lines 76-77 and 81-83; please address this inconsistency.

In lines 486-488, the last two sentences of the conclusion are unclear. They serve as a general summary but do not align well with the content of this study. These sentences should be removed, and a new summarizing statement that is more focused on the results should be included.

Comments on the Quality of English Language

English is generally good, but some parts need to be edited for clarity and to be more detailed.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript has been substantially improved.

Author Response

Thank you for your valuable comments.