Effects of Biochar Type on the Growth and Harvest Index of Onion (Allium cepa L.)

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The study investigates the impact of peanut, rice, and cocoa biochars on the growth and productivity of onions (Allium cepa L. var. Alvara), focusing on how these biochars affect functional traits like height, leaves, and roots. Although the authors set out to determine the optimal biochar application rate, the findings, according to the authors, reveal that while overall plant growth did not significantly improve with biochar application compared to a control group, specific application rates (1.5% for peanut and 1.5% & 5% for rice biochar) did seem to marginally enhance the Harvest Index and increase dry weight values of onions. This suggests that while biochar has potential benefits in terms of yield enhancement, its effectiveness is dependent on the type of biochar used and the specific application rate. The study underscores the necessity for further tailored research to optimize biochar use in agriculture, enhancing crop productivity sustainably.

I find the manuscript generally well-written and organized, and easy to follow. I recommend that it be published after just very minor revisions suggested below:

L 172 & Line 201: Both bear the same section heading/sub-title (section 3.2...); check.

L 215 - 216 (Table 3): Check the formatting of the font type; it seems different from what's used in the entire manuscript.

L 218-219 (Fig 2): It seems like the control HI is plotted against a 1% biochar application rate. I thought the control had 0% biochar. Check.

L 221-235: It seems to me like these increases are marginal and should not be generalized (L 221-223). In Fig. 3, briefly define the CLD (alphabets) just for readers who may need the context. Also, by visual observation of the plots and images (Figs 3 & 4), it would seem like the application rate of 1% peanut (not 1.5% as stated by the authors) provided a relatively higher value instead. Double-check this. Lastly, why did the authors not say anything here about the cocoa biochar even if with reference to its control? If any of these points are modified, please do revise the other sections, discussions and conclusion, for consistency.

 

Author Response

Thank you sincerely for your insightful review of my manuscript, "Effects of different biochar types on the growth and harvest index of Onion (Allium cepa L.)". Your feedback has been invaluable in improving its clarity and scholarly merit.

I particularly appreciate your suggestions. This will greatly enhance the overall coherence of the work.

Thank you again for your expertise and dedication.

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The tile. “Different”  seems redundant. “Effects of biochar type” sounds better.

The abstract needs to rewrite. The current version is quite confusing.

Use accurate terms. They are peanut, rice and cocoa biochars, rather their husk biochars!. The purpose is to improv yield. But no qualitative or quantitative data are present for the yield improvement.

While authors claimed cocoa biochar richest in key elements, this type of biochar did not mention any more thereinafter. Also list the so-called key elements.

Should give the statistic information for “not significantly” (e.g., p > 0.05?)

Give the numbers of “higher dry weight values”. Please also clarify if the value is referred to onion bulb or the whole plant.

The two conclusions in the least sentence seems conflicting each other. Presentation of the solid quantitative data of the plant growth and yield parameter impacted by the three types of biochars may be helpful for readers to see if the two conclusions are experimentally supported or not.

Authors needs to revise the main text in the  same way.

Other comments

LL41-47. The biochar book published by Soil Science Society of America may be cited to stress both  agricultural and environmental significance of biochars

Guo et al. (2016) Agricultural and Environmental Applications of Biochar: Advances and Barriers, Soil Science Society of America, Inc., Madison, WI. pp. 504.

LL112-113. Check grammar correction of this sentence.

LL115-116. Need  the reference for the AOAC methods.

LL131-133 .such application rate information should be present in Abstract.

Table 1. any SD values for these data. Or should give information if the values of each row is statistically significant different or not between the three biochars. The statistic treatment information is needed to support your claim “The composition of biochar has a significant difference due to the variation of the 161 feedstock” LL161-162.

LL242-268. The discussion on effects of pyrolysis temperature is irrelevant as you made the biochars at a single pyrolysis temperature.

 

Comments on the Quality of English Language

English is generally Ok 

Author Response

Thank you sincerely for your insightful review of the manuscript, "Effects of different biochar types on the growth and harvest index of Onion (Allium cepa L.)". Your feedback has been invaluable in improving its clarity and scholarly merit.

I particularly appreciate your suggestions. This will greatly enhance the overall coherence of the work.

Thank you again for your expertise and dedication.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript "Effects of different biochar types on the growth and harvest index of Onion (Allium cepa L.)" is devoted to determining the optimal application concentrations of different types of biochar (derived from peanut, rice and cocoa husks) for onion cultivation. Authors found that despite the absence of a statistical difference in growth rates, the use of biochar contributed to an increase in the dry weight of the bulbs, and, consequently, their nutritional value. The work established the optimal rates of biochar application for growing onions. In my opinion, the manuscript deserves publication after correction of the following points:

 Please expand the annotation by indicating specific values (or percentages) of the increase in the yield index.

Add keywords: biochar, onion

Line 21 Please check the Latin spelling of the plant species (use the full name with an abbreviated reference to the work in which the species was first described in the scientific literature)

Line 74 (Niu et al., 2022; Wijaya et al., 2023) Please format the references using the template format (numbers in brackets).

Lines 84-86 Please explain what is meant by this part of the sentence or rephrase it. “…with biomass allocation favouring roots in response to below-ground limitations and favoring shoots in response to above-ground limitations…”.

Write the variety name as follows: ‘Alvara’

Lines 115-119 Please provide a reference to the methodology.

Figure 2 Label each graph in the figure with separate letters (a, b). On the diagram HI, it is better to place the control closer to the 0 value.

Lines 172, 201 Check the subsection numbering

Lines 244-245 Check and change (alkaline compounds)

Lines 281-284 Please explain what C/N ratio causes nitrogen immobilization (20, 25-30)? 2 sentences are strangely related to each other, you use the word “Conversely”. It is better to rewrite this part of the text to make it clearer.

Line 328 Check and change “laom soil”

Lines 361-366, 380-381 In my opinion, some of the references you used relate only tangentially to the study and are best left out of the discussion or give recommendations on the combined use of mentioned fertilizers/elements [44, 51, 53, 54].

Conclusions: Give clear recommendations for the application of each type of biochar for the optimal effect on the yield index in terms of kg∙ha^-1.

Comments on the Quality of English Language

Lines 95-96 Check and change “…would positively impact growth and functional traits…”

Line 105 The experiment was developed with Allium cepa variety (was conducted on…)

Line 205 Biochar application significantly impacts the dry weight… (influences)

Line 255 Check and change “aromacity”

Line 326 Check and change “Also, spraying amino…” (In addition,…)

Line 331 Check and change “defficient irrigation”

Lines 346-347 Please rewrite this part of the sentence “…with some organs like roots showing no significant response, like the results obtained in the present study…”

Check the use of the word "Impact" throughout the text.

Author Response

Thank you sincerely for your insightful review of my manuscript, "Effects of different biochar types on the growth and harvest index of Onion (Allium cepa L.)". Your feedback has been invaluable in improving its clarity and scholarly merit.

I particularly appreciate your suggestions. This will greatly enhance the overall coherence of the work.

Thank you again for your expertise and dedication.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors addressed my concerns properly. The revised manuscript may be acceptable. But there is still one concern on the terminology. That is:

 The first sentence of abstracts stated as “this study investigated the potential of peanut, rice, and cocoa biochar”. Indeed , the biochars are from their byproducts husks (or peanut shell, rice husk and  cocao shell). Author should use the correct term in abstract. Also check the entire manuscript (e. .g, Table 2).

Author Response

Thank you very much for your thoughtful review of my manuscript. Your feedback has been immensely helpful in enhancing clarity and scholarly value. I deeply value your suggestions.

Author Response File: Author Response.docx