Water and Soil Nutrient Dynamics of Huanglongbing-Affected Citrus Trees as Impacted by Ground-Applied Nutrients

Round 1

Reviewer 1 Report

The present work is an interesting outcome. 

However, several things should be improved.

1) They should reorganize their manuscript. The authors should select the most important tables and figures. They presented too many things.  Minor outcomes should be added as supplementary data

2) Design of tables and figures are poorly presented:

Figure 7, 8 and 12: It's hard to understand these figures. And the black square boxes in nitrogen rate of 224 are wrongly inserted?

Figure 13 and 14: Wrongly black square boxes are inserted.

Table 4: It doesn't fit into the template. And, it's not friendly organized for readers.

Author Response

Dear reviewer:

These are merely additional information. All the comments are added and edited in the article. 

1) They should reorganize their manuscript. The authors should select the most important tables and figures. They presented too many things.  Minor outcomes should be added as supplementary data

Response 1:

Table 1 was just added as a supplementary data used to consolidate the study. Hence, it is removed to focus only to the actual data collected and analyzed in the study. 

2) Design of tables and figures are poorly presented:

Response 2: Table 1 and 2 has the data as well as the analysis of variance (ANOVA) at the bottom of the table. The factorial effects of these tables now contain only those factors that have only significant effects in any of the four seasons. This will ease to the reader to understand the content of the table.

Figure 7, 8 and 12: It's hard to understand these figures. And the black square boxes in nitrogen rate of 224 are wrongly inserted?

Response 3: I added the following phrase “(0–15 cm, 15–30 cm, and 30–45 cm)” to make it clear to the reader. I agree that the black boxes were not entirely transparent (88%) that the letters were in some boxes were totally black. I edit each of them; now the black box are clear.

Figure 13 and 14: Wrongly black square boxes are inserted.

Response 4: the black boxes were not entirely transparent (88%) that the letters in some boxes were totally black. I edit each of them; now the black box are clear.

Table 4: It doesn't fit into the template. And, it's not friendly organized for readers.

Response 5: Table 4 (now table 3) is the ANOVA of soil nutrient of the ten essential nutrients. The factorial effects of these tables now contain only those factors that have only significant effects in any of the four seasons. This will ease to the reader to understand the content of the table.

Background and include all relevant references?

Response 6:

The background and reference has been edited and updated.

Is the research design appropriate?

Response 7: The experiment had three main effects namely: two rootstocks × three N rates × three secondary macronutrients rates. The treatments were arranged as a split-split plot design comprised of the largest plot assigned with the rootstocks, the intermediate sub-plots were the N rates (168, 224, and 280 kg ha^-1), and three soil-applied secondary macronutrients (Ca or Mg-thiosulfates) rates and untreated control trees were set as the sub-subplots. Within each the intermediate N rate plots, trees received one of the following treatments: untreated control, and one of the three secondary macronutrients (Ca or Mg at 45 kg ha^-1 and Ca + Mg at 22 kg ha^-1 each) replicated four times. The K fertilizer (K₂O) was applied at 168 kg ha^-1 and applied to the largest plot uniformly to all trees.

Response 8:

Are the methods adequately described?

The materials and methods has been edited and improved very well. Please, see the updated version of the article.

Thank you.

Author Response File: Author Response.docx

Reviewer 2 Report

Dear authors,

Thank you very much for very interesting reading. Before the publishing of this manuscript, I have some comments, suggestions and few corrections that should be made.

I like the layout of the manuscript and it was easy to follow. Honestly, I never heard about such HLB disease, so as a general reader I would like to add little more information about it (e.g. what caused this disease?).

Please, also state the novelty of this research? Are there any more research activities focusing on this problematic?

I would recommend to add the map of the study area in the material and method part.

Author Response

Dear reviewer,

Thank you for the comments. I have addressed all the comments as per the demand. These are additional comments but all the comments are edited in the original article attached. 

Thank you very much for very interesting reading. Before the publishing of this manuscript, I have some comments, suggestions and few corrections that should be made.

I like the layout of the manuscript and it was easy to follow. Honestly, I never heard about such HLB disease, so as a general reader I would like to add little more information about it (e.g. what caused this disease?).

Response 1:

As per the request I included the following sentence in the introduction part:

“Huanglongbing (HLB), caused by 'Candidatus Liberibacter asiaticus', was first seen in Florida in 2005 where currently dispersed throughout the commercial citrus groves”.

Please, also state the novelty of this research? Are there any more research activities focusing on this problematic?

HLB is a bacterial disease with no known any remedy in sight thus far. Researchers are studying the disease in different discipline: pathology, entomology, plant physiology, horticulture, etc. As part of the study in different discipline, the soil and water science department in the University of Florida is studying to maintain the health status of the trees while surviving the disease. Therefore, the research is novel, up-to-date, and vital for the citrus industry in the region. Besides, it is part and parcel of team study across several sites in Florida.

I would recommend to add the map of the study area in the material and method part.

I wish I would have added a map of the study site. However, one of the editors suggest to focus on the main findings of the study that I even omitted a supplementary table from the article. I added the exact GPS of the study site in the materials and methods part as a middle-ground to the map.

With best regards,

Atta, Alisheikh A.

Author Response File: Author Response.docx

Reviewer 3 Report

My remarks, questions and corrections are in sticky notes above the relevant parts in the manuscript (see attached).

Comments for author File: Comments.pdf

Author Response

Dear reviewer,

These are additional comments to the specific required for more clarification. I have edited and addressed all the comments you gave me. Please, see the original article attached at the bottom of this interface.

Why these doses?

Response 1:

The doses were recommended by the University of Florida, Institute of Food and Agricultural Sciences for citrus nutrition. This sentence was included in the materials and methods section.

A more detailed explanation is needed here (materials and methods).

Response 2:

The trees received daily irrigation with irrigation scheduling determined using mobile smart devices (e.g., smartphones, tablets), apps available on iPhone or androids (http://smartirrigationapps.org/). SmartIrrigation apps are devices invented to estimate irrigation duration for specific crops (i.e., avocado, citrus, cotton, peanut, strawberry, and vegetables) using reference evapotranspiration from Food and Agricultural Organization (FAO) Penman-Monteith and crop coefficient associated with real-time meteorological information acquired from the Florida Automated Weather Network near the study site.

Irregular citation

Response 3:

All irregular citations were edited and followed the same pattern.

How was ET0 determined? (It's not a measured parameter)

Response 4:

Yes, the ET0 model was produced based on Food and Agricultural Organization (FAO) Penman-Monteith and crop coefficient associated with real-time meteorological information acquired from the Florida Automated Weather Network near the study site (https://fawn.ifas.ufl.edu/data/reports/). The information is edited and included in the article.

The results gained from the study of HLB-affected trees are not compared to those gained from the study of healthy trees, therefore the importance and effects of HLB on the investigated parameters are not really highlighted in this paper.

Any difference from non-HLB-affected trees?

Response 5:

It is less likely to get an HLB-free citrus tree in the Florida citrus industry. We conducted a foliar HLB laboratory analysis for each tree under the study at the beginning of the study in April 2017. The result indicated that the trees were 100% infected with Candidatus Liberibacter asiaticus. Results with quantitative real-time polymerase chain reaction (qPCR) indicated that trees budded on Cleopatra and Swingle rootstocks were positive for Candidatus Liberibacter asiaticus with Ct value of 25.9 ± 0.25 and 24.7 ± 0.36, respectively (information included in the article in the materials and methods section). Our comparison was to see the difference between the secondary macronutrient treated trees with the control untreated trees. Therefore, our hypothesis focused if we treat HLB-affected trees with essential nutrients, the health of the tree will be reversed; thus the industry maintains producing high quality and quantity fruits using nutrient therapy. 

Spelling, punctuations, and grammar

Response 6:

All other spelling, punctuation, and grammar comments were addressed as per the request.  

Thank you for your time.

With best regards,

Atta, Alisheikh A.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors improved the manuscript. However, they didn't consider partly my suggestion. As a reminder, I would say that they present too many figures and tables which easily distract readers and miss the main points of the outcomes. The authors, seemingly, haven't put themselves into the reader's shoes. I suggest them again putting some minor tables and figures in the supplementary information. 

Another thing that I noticed when I was reading the improved version is that there is no consistency in legends for tables and figures (e.g. font size and space size). 

Author Response

Dear reviewer,

Thank you so much for the invaluable comments. I have moved six figures and two tables to the supplemental section. I just focused on the original findings of the research work. For details, please see the original article.

With best regards,

on behalf of the authors

Author Response File: Author Response.docx