Effects of Pruning Mulch on Nutrient Concentration of Avocado (Persea americana Mill.) Fruit under Subtropical Conditions

Round 1

Reviewer 1 Report

I have read the manuscript and satisfied myself that the work is of high quality and publishable.

The authors need to pay attention and correct the following:

1. The objective/ hypothesis should be clearly stated in the abstract,

2. the key words in the abstract should be in alphabetical order.

3. The objective should be made clear and the authors should state their hypothesis towards the end of the introduction section.

4. The sampling design should be clearly stated. Is it a complete randomised block design with the terraces representing the blocks or a factorial design where time has been added as a factor.

5. Sample Preparation and analysis (Ln 161- 173)- The year and model of equipment used should be stated in all cases.

6. The PCA results were well presented in the results section. However, they were not discussed is the discussion section. The author may do justice by discussing the PCA results or even use the PCA to support other findings where possible.

7. Conclusion:  In paragraph 1, the alternate bearing processes and water availability were not core measurements and cannot conclusively be attributed to changes in size and weight. 

8. The objective and hypothesis were not clearly stated in the beginning, hence it is difficult to ascertain if either of them were achieved.

 

 

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

An interesting experiment to use plant waste to mulch avocado trees. All parts of the publication are well written. Additionally, tables comparing the results of nutrient content with the results of other authors are provided. Small suggestions for future use are included in the text of the publication. It's nice to review thoughtful publications. 

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

The basis of the work is vague. What did the authors expect? Was it a trial for organic agriculture (avoiding chemical fertilizers)? How do you find steady composition garden litter? How much was applied, when and every year or once? What did the organic materials contain? There is no information present.

Even though inorganic fertilizers were applied (how much not shown), what is the meaning of applying organic mulches (again how much and what they contain is not shown).

The work is unconventional. If the authors wanted to test the effect of organic mulches on avocado, leaf analyses should have been performed, inputs and outputs of nutrients should be calculated, and a discussion should be developed on the uptake of nutrients towards the transpiring leaves (almost entirely) and, to a minor extent, to fruit, and the movement of nutrients from leaves to fruit in conjunction with soil water (which was continuously applied over the year). But there is no data on yield or # of fruit per tree to calculate outputs or the effect of year on fruit size and composition.

 

L19 if the pulp contains mainly these elements, what about the main fruit nutrients N and K?

L53 where do you find many peels and stone? Is there an industry making guacamole dip? What about the leaves falling throughout the year? Is there normal mulching of prunings as in other fruit crops?

L56-66 again you describe what fruit residues are useful for, but it is not clear where you can find them!

L66-68 useless information

L77-80 again not related information, there are numerous works on mulching to fruit trees, why discussing the one season vegetables?

L83-84 application of what?

What happened during 2013-14 and 2014-15?

Fig. 1 rainfall is shown where? If the heavy rain months during fall were getting 5 mm the most, the total per year cannot be added. (and the area is drier than Sahara)

Fig. 2 the distance between trees shows 500 trees/ha and you say there were 300 trees/ha!

Only, when the reader reaches Fig. 2, the treatments are understood. Up to that moment it seemed that all mulches were mixed together and applied in 1 treatment!

L134-137 so the treatments are vaguely described here. Question: this mulch was applied once at 2012 or every year and, of course, how much of each was applied per tree or ha? And what did these mulches contained as far as inorganic nutrients are concerned?

L161 how did you measure fruit volume?

L163 the refractometer does measure sugar content, but soluble solids which are not only sugars.

Table 1, I do not understand how the uppercase letters were added. There is no following from the larger to smaller mean value on each fruit part. Less problem with lowercase letters: you put a in the larger or the smaller mean?

L239 but N and C are in g per 100 g

L240-242 unclear sentences, which study has actually higher nutrient content?

L247 resistance to what?

L254 rainfall was higher in 2012-13 than 2015-16 and ETc was not that different, except if in a couple of months the minor difference gave all the differences. What about the yield or the number of fruit per tree? If they are different, fruit size and mineral composition will change.

L256-257 but you did not measure any of them except temperature

L262 you mean the experimental orchard or other orchards in the literature? Because your orchard was facing north, thus available light is not very high.

L265 no, the water is not lost, the sugars act osmotically to hold the water so it is not transpired (in a short unconventional description).

L272 you presented nothing on alternate bearing over the years

L279-282 so, finally, where did Tamayo et al. measure the nutrients?

L290 but in Fig 4 they did not differ

L295 but 2017 was the dryer year

L297-298 but you irrigated every day all the years with the same quantities

L303-304 the sentence is unclear, what is 55-70%?

L300-309 rewrite this because your values are not higher than the others, as more nutrients were higher in Tamayo et al than in your study. What about the N, very important as protein in food?

L322 unclear sentence: what do you mean avocado crops?

The Conclusions section is unacceptable as most of the conclusions are ‘wishes’ and not data.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Again, there is nothing on mulch nutrient content.

Again, you do not discuss the comment on the avocado fruit residues in the text.

Refractometer measures soluble solids and not sugar.

In the figure 1 I wanted you to clarify that precipitation is shown on the left Y-axis and not on the rigth Y-axis!

Again, the reader does not understand the use of lettering in Table 1.

Author Response

Reviewe 3 (round 2)

Many thanks to the reviewer for his comments on the new version. We have taken them into account to improve the manuscript. The following changes have been made :

 

Again, there is nothing on mulch nutrient content.

The nutrient content of the different types of much has been added as supplementary material as it has been published previously as noted in the manuscript.

Again, you do not discuss the comment on the avocado fruit residues in the text.

Thank you for this comment, the section was revised to improve the understanding.

Refractometer measures soluble solids and not sugar.

Thank you for this comment, the section was revised to improve the understanding.

In the figure 1 I wanted you to clarify that precipitation is shown on the left Y-axis and not on the rigth Y-axis!

In the figure 1 I wanted you to clarify that precipitation is shown on the left Y-axis and not on the rigth Y-axis!":

We have modified the title of figure 1. The precipitation values seem low because the graph shows the average monthly rainfall, reference evapotranspiration, relative humidity, and temperature. Accumulated precipitation and evapotranspiration are specified on lines 138-139.

Again, the reader does not understand the use of lettering in Table 1.

The legend of table 1 has been modified (line 250) to clarify the meaning of the letters
 

Author Response File: Author Response.docx