Agroecological Screening of Copper Alternatives for the Conservation of Soil Health in Organic Olive Production

Round 1

Reviewer 1 Report

Abstract:

Lines 20-22: Check this sentence. Table 6 shows differences at 30-60 cm but no at 0-30 cm.

Keywords: reduce to five keywords.

1. Introduction

Numeration of references is required and the order should follow the order of appearance in the main text. English should be revised.

Line 42: "in pertinence in tandem” sounds redundant. The whole sentence can be simplified.

Line 47: Description of the MAF-ORI should be in Material and methods (from line 50 to 52)

Line 52: The parts listed below this sentence (1.1, 1.2, 1.3, 1.4 and 1.5)  don´t correspond with the two parts in Results.

Line 61-67: The concept of this sentence could be “Agricultural management that includes copper can lead to environmental contamination (plant, soil properties)” Text can be reduced to get to this idea.

Line 71-73: Reduce the sentence to this concept “Copper and copper compounds can lixiviate with the action of water and can be leached into groundwater”

Line 81: correct “scan” to “can”

I recommend to delete the sub-sections in the Introduction  

Line 84. Complete de Indicate number of the Official Gazette from References .(

Line 88-89. Rewrite the sentence and move to Material and Methods-Description of the experimental site (Izmir? Akhisar-Manisa Province?): The case farm is in a lowland suburban area where the production of olives is dominant.

Line 89-91. Copper application is lower than in other countries (which ones? In general? Describe situation in the Mediterranean area, other areas of the world,..).

Line 98-99. This sentence can be in line 96 after the production information.

Line 120: Reduce Section 1.3. Delete the historical development of the urban agriculture and commentaries related to legislation. Establish the fact that changes in the land use has addressed to new problems related to previous Cu accumulations in water, compost and clay soils. That a new generation of farmers demand new production techniques to enrich agrobiodiversity. Linked with lines 172-174.

Line 196: This paragraph is confusing; explain section (b), evaluate the effect of “copper leaf-spray application on” olive leaves? If so, :

Evaluate the effects of:

a)       Fertilizers and BCAs on olive leaf spot disease and copper pollution in soil

b)      Copper leaf-spray application on olive and fruits

c)       TWSP content in olive fruit as a preventing factor…

Material and methods

It would be more explicative to order the information in sub-sections like:

“Study sites” containing text from lines 50, 51, 208-211; Figure 1a

“Experimental design and field management” containing Figure 1b, Line 212-217, Line 234-250, including Tables 2, 3, and 4. Please, include a higher resolution photo in Figure 1b.

“Sampling and measurement” Lines 203-205, Table 1, 218-228, 251-279.

“Statistical Analysis” Lines 280-287.

Line 204: leaf samples were collected from “the plots in preparation”? for lab analysis. What does mean “plots in preparation”? Plots were not stablished yet?.

Line 206. Table 1 contains repetitive information. All samplings were taken in Autumn for the three seasons for the three types of sample. The only differences lie in the sampling method. Consider the option of replacing the Table by a paragraph like:

“Samplings were collected in Autumn for the three seasons (2018-2019, 2019-2020, and 2020-2021). Soil samples were collected according to Kacar (1977) and leaves and fruits according to Kacar & Inal (2008) and Reuter & Robinson (1986).”

Lines 207-211: I suggest to re-write this paragraph. Below, there is a paragraph suggestion:

“Biological control agents (BCAs) were included as possible alternatives to copper against “olive leaf spot disease”. The experimental site was stablished in an organic olive orchard which is 28 years old “Domat” table olive variety (distance between trees are: 5 × 7.5 m), located in Zeytinliova, Akhisar, Manisa Province (Turkey) (38°96’3.7’’ N 27°69.855’ E). The trial lasted three years from September 2018 to September 2021.”

Line 227: Explain “essential macro and micro elements…. were determined as sufficient as classified by Anonim (1993)”

Line 234: Table 2 is hard to follow because the rows are confusing. First row for 2018 , Early-April and then the column of “content of applied certified organic commercial fertilisers” A is for 2018? And B for 2019? Or A, B and C were applied each year?

I don´t understand the meaning of “Totally” here: “Totally 0.8 l.ha^-1.year N and P, application divided 4.year^-1.” Corresponds with this? An annual doses of 0.8 Liters per Hectare of N and P, applied in 4 times.

Check “Bacillus subtilis” and correct in Tables 2, 3 and 4

Line 235: after Table 2, a weight/weight à ^a weight weight or (a) weight/weight. Although I would remove “(w.w^-1)^a “and substitute by “(w/w)” that is standard and doesn´t need a quotation.

Line 241: Information in Table 3 is already in Table 4, isn´t it? Then, I would merge both Tables in one.

Line 246: Is “ORI” missing here? “organic fertilisers were tested by MAF-“ORI”.

The trial, with a total of 88 olive trees, consists of 11 treatments +4 repetitions +2 trees per plot. Details of the different applications in this study are shown in Table 4.

Table 4: I would line up the rows in the Table, each number with the correspondent treatment and Application details. The same could be useful for Table 2  

Line 251: I suggest rewriting the paragraph to make it easier for readers:

“A scale from 0 to 5 was used to score the disease (Figure 2). Disease severity was calculated according to the Townsend–Heuberger Formula = [∑ (no. of plant in category × category value)] × 100/Total no. of plants x max. category value) [Townsend and Heuberger, 1943].”

Categorie value = disease scale?

Results

Line 290: It is very important that the object of study is the conventional to organic transition of the olive orchard. This is an interesting study and should be highlighted and include in the objectives.

Line 294: Table 5: CV is missing. In Line 295, Include number of replications (n = ?).

Line 295: instead of “was applied for long years”, replace it with either “was applied for long time” or “was applied for many years”  

Table 6. Correct the Table header, 30-60 cm is misplaced. Line 307 gives ranges of copper content different for soil (0-30 cm) in 2021, is that right?.

Line 305: I suggest this correction in the paragraph to make it shorter and clearer:

“The results of 2 consecutive years (organic conversion period 2020 and 2021) of the soil copper content at 0–30 cm depth ranged from 3.59–3.75 mg kg−1 (2020), 1.12– 4.23 mg.kg−1 (2021) and in samples taken at 30–60 cm depth, the results ranged from 1.81–3.40 mg kg−1 (2020), 0.80–3.43 mg.kg−1 (2021). The minimum and maximum copper contents in leaves and fruits ranged between 7.80–78.43 mg.kg−1 (2020), 6.13–6.70 mg.kg−1 (2021) and 2.51–2 .98 mg.kg−1 (2020), 2.16–2.45 mg.kg−1 (2021), respectively.”

Line 315: [According to “Organic-Plus Project” “Work Package Plant” report for field labs (D3.8)] I think this sentence refers to a report elaborated under the Funded Project that supported this work but I guess it is not necessary to mention it in this section.

Line 313: Disease severity was scored using the Townsend-Heuberger formula. How did you measure the efficiency levels?

Discussion

I don´t understand the first paragraph, please rewrite it.

What do you mean by “samples contain sufficient copper? Over 0.2 mg/kg?

Line 359: Did you found seasonal differences of the copper values in leaf samples? Since your leaf samples were analysed in Autumn, you should compare your results with those obtained by Aydogdu in September (8.13 mg/kg).

Line 363: Your results of initial leaf copper (Table 5 and line 303) are much higher than 8.13 mg/kg.

Line 365: About the accumulation of copper in the trial site (data in Table 5 compare to Aydogdu’s values in Lines 365 and 366), it seems that this accumulation was remediated after four years. Is it right? Any idea about where that copper went? It seems that it goes deeper in the soil and that could explain that copper levels at 0-30 cm are similar in Table 6. Probably it would be interesting analyse soil samples more deep.

Author Response

Dear Reviewer,

Thank you very much for your suggestions. We considered all your comments in the new version of the manuscript.

We chanced the name of the draft adding "health".

Regards,

Dr. Alev KIR

Reviewer 2 Report

The manuscript deals with a relevant subject to Agronomy related with agroecological copper alternatives against olive leaf spot. However, there are some aspects in the ms that require improvement, namely in the introduction and results sections to which the authors should address. Moreover, The English should be revised in order to make the manuscript more readable and fluent. Thus, I recommend that the manuscript should be accepted after major revision.

Other points:

1.   Line 23: bioindicator instead of bio indicator.

2.   The introduction section should be reformulated, including deleting titles. The 3 pages should be very simplified. Many references are also lacking in the introduction section.

3.   The fertilization program should be clarified.

4.   Figure 1: unnecessary.

5.   Table 6, 2020:  same soil available Cu levels (0-30 cm)?

6.   Results section (3.1) should be reformulated.  Reference to treatments should be included (not only the minimum and maximum values).

Author Response

Dear Reviewer,

Thank you for your comments. 

We changed all parts following your suggestions in the manuscript.

We added "health" in the name of the draft.

Regards,

Dr. Alev KIR