Irrigation Management Based on Theoretical Requirements Reduces Water Consumption in Apple (Malus domestica Borkh.) Orchards without Effects on Fruit Yield and Components
Round 1
Reviewer 1 Report
In general, the paper is well-structured and very well written and referenced, but some details should be explained in the document.
In the document authors will be able to see the comments from the Reviewer.
Comments:
It is important to clarify in “Irrigation method”, the description of Irrigation Treatments. The theoretical volume of water presented is a fundamental part of the paper and it is not well exposed.
Please, authors should look at the comments attached.
As well, as a general comment, results with the “theoretical water volume of water” are interesting but it would have been appropriate to test a deficit irrigation scenario, to contrast that a lower amount of water it can be even reduce.
Comments for author File: 
Comments.pdf
Author Response
Answers Reviewer 1
Irrigation management based on theoretical requirements reduces water consumption in apple (Malus domestica Borkh.) orchards without effects on fruit yield and components
WATER-1975857
Line 148: Please, explain 0.5 emitters per tree. This mean that is 1 emitter (microjet) per two trees. A new Figure 2 explains the irrigation scheme.
Line 149: Please add the radius or diameter of irrigation. Add the distribution uniformity of the microjet system. The wetted diameter of the emitter was 2.2 meters (this mean one emitter per two trees, as was the irrigation design for this project. Figure 2a). However, twice in a month emitters discharge was measured without differences during the irrigation season.
The distribution uniformity was not determining due that we use TDE as the efficiency parameters.
Line 152: It would be interesting to ass an irrigation scheme. Done (Figure 2).
Line 162: Please, justify this value. TDE is the total distribution efficiency and describes the water distribution in relation to the water requirement by the trees considering excess and deficit (Holzapfel, 1984). In the case of small areas like the research surface, 95 % is a minimal reasonable value based on our studies.
The equation is:
where Xi is the water applied in tree i, and xr is the water required by tree an n is the number of trees
Reference: Holzapfel, E.A., 1984. Selection and Design of Surface Irrigation Methods. PhD Thesis University of California, Davis. California, U.S.A.
Line 173: The shade fraction is related to cultivar frame??? Please, specify shade fraction. Fc is an estimated dimensionless crop factor associated with P, which corresponds to plant canopy coverage where P= AS/H L (0.1 < P < 0.7), AS is the shaded area at noon (m2) determined by measuring the shadow diameter projected on the soil by the plant, in several directions; H is the distance between rows (m) and L is the distance between plants within the row (m). P of the plants at noon was determined monthly throughout the irrigation season.
This explanation is added to the text, below Eq. 3
Line 174: Please, indicate the regression analysis used. K1 y K2 are constant values following the calculations outlined in [18] (Holzapfel et al. (2004)), with constant values obtained from [9] (Holzapfel and Arumi (2010)). However, the original methodology to obtain K1 y K2 was published by Fereres and Goldhamer (1990):
- Fereres E, Goldhamer DA (1990) Deciduous fruit and nut trees. In: Stewart BA, Nielsen DR (ed) Irrigation of agricultural crops. Agronomy Monograph 30. ASA-CSSA-SSSA, Madison, WI, pp 987–1017 (added to the text).
Line 179, Table 1: There are big difference between cultivars in P, can you explain why? ‘Brookfield Gala’ is a four-year-old orchard and ‘Royal Gala is a 10-year-old orchard.
Line 202, Table 2: Authors should include the irrigation time for treatment T1 (or the interval in each case). Are those hours each irrigation??? Irrigation time is included now; also, it is added “hours per irrigation”.
Line 414: Plant are not stressed at any point of the study!!! That is true. We did not try to stress the trees, we only sought to study a possible water saving without causing a decrease in yields and quality. As a matter of fact, we also measured stomata conductance, with no differences between treatments (data no showed).
Line 432: Please, indicate the value of leaf water potential, authors consider the plant stressed (revise more bibliography than only Bhusal et al.). Two authors have been added: 30. Naor et al. (1995) and 31. Mpelasoka et al. (2001)
Author Response File: 
Author Response.docx
Reviewer 2 Report
I would like to thank the authors for their scientific efforts. The topic is meaningful. The subject of this paper is very interesting to the readers. Therefore, in my view, this paper can be accepted, but it has to be improved to meet the requirement of water with a major revision and some clarification on raised comments before the publication.
General Comments:
English grammar, sentence framing and lengthy sentences are to be checked and modified throughout the manuscript.
Titil
Point 1: It is better to add the study area in the title if possible.
Point 2: The title should be significant to attract the readers
Abstract
Point 3: The current abstract need to be improved, the authors should clearly show some background and more details of the Irrigation management results and its further implications.
Point 4: The authors need to include the analysis method in the abstract (ANOVA).
Keywords
Point 5: lines 25 – 26. The keyword (Malus domestica Borkh) is not in the title of the article or in the abstract. it must be added or removed from the keywords.
· Please add the study area in Keywords.
Introduction
The introduction can be improved including more references, and checked the English grammar, sentence framing and lengthy sentences and modified throughout the manuscript.
Point 6: line 106. It is necessary to write the fall name of the figure 1, the same for figure 4 (line 243) for the figure 9 (line 383).
Materials and method
4.1 The study area:
Point 7: Line106. The figures should be placed in the center, and the name of the figure should be written with the completed form (Figure 1).
Point 8: From lines 115 to 120: You talk in this paragraph about the climate of the area and the precipitation without mention the references. Please add the relevant references for the information presented.
Point 9: From lines 121 to 131: Same remark for this paragraph (References!!).
Point 10: Line 136: you are talking about texture analysis in accordance with the international system for three soil without mentioned the reference of the international system.
Point 11: Line 156: It is necessary to write the fall name of the equation 1.
Point 12: Line 178: same remark for equation 3.
Point 13: Line 183: Same remark for equation 4.
Point 14: From lines 163 to 175: All equations number should be mentioned in the text.
Point 15: The line 244: The statistical Analysis: you should mention the reference form previous works.
Results and Discussion
Point 16: Line 283: It is necessary to write the fall name of the figure 4.
Point 17: The authors presented in lines 283 to 285’’ when no water was applied in either treatment in the 2009-2010 season due to the Earthquake of February 27, 2010’’. The authors need to mention the reference of the origin study.
Point 18: From 318 to 328: Please rephrase this paragraph.
Point 19: From 448 to 469: the authors should be improved to discuss how the findings of this study support or criticize the findings or arguments of previous studies.
Point 20: Figure 5 (T1(a), T2(d); T1(b), T2(e)): please define the X axis. Same remark for the figure 7 and 8.
- Finally, the English language used needs editing throughout with a moderate level of change required.
Author Response
Reviewer 2
Irrigation management based on theoretical requirements reduces water consumption in apple (Malus domestica Borkh.) orchards without effects on fruit yield and components
WATER-1975857
Point 1: It is better to add the study area in the title if possible. The study area is shown in the third line of the Abstract. We thought it would lengthen the title excessively.Point 2: The title should be significant to attract the readers. It has not been easy for us to find a more attractive title: in general, they are too long.
Abstract
Point 3: The current abstract need to be improved, the authors should clearly show some background and more details of the Irrigation management results and its further implications.
We rewrite the Abstract, following the evaluator's instructions and trying not to exceed the 200 words allowed.
Abstract: This research examines the effects of two irrigation strategies on water use efficiency and fruit yield components of ‘Royal Gala’ and ‘Brookfield Gala’ apple orchards in south-central Chile. The study was carried out during the 2008-2009 and 2009-2010 growing seasons at two sites. A randomized block experimental design was established with two water application treatments: theoretical volume required by the plant (T1) and farm protocol (T2). Soil water content, plant water potential and yield components were evaluated. The soil water content in T2 was near field capacity while T1 was between the permanent wilting point and field capacity for both seasons and varieties. With T1, the seasonal volume applied was 21 to 28 % less compared to T2, with season savings of 1,600 m3 ha-1. No effect on plant water potential was observed. In ‘Royal Gala’ the lower volume applied in T1 did not lead to significant differences in fruit diameter, weight, or yield in either season as compared to T2. In ‘Brookfield Gala’, yield during the 2008-2009 season increased significantly, by 22.9 % in treatment T1, and in the 2009-2010 season, significant reductions (p<0.05) in fruit diameter (5.3 %) and weight (12.9 %) were observed in T2. Productivity per volume of applied water in T1 was 32 % to 56 % greater than that obtained with T2. The results show the effectiveness of the irrigation strategy considering the theoretical volume of water required by the plant.
Point 4: The authors need to include the analysis method in the abstract (ANOVA). If we incorporate ANOVA related words in the Abstract, we will exceed 200 words by too much. We think point 2.2 (Experimental Design) and 2.8 (Statistical Analysis) have the necessary information required by a scientific manuscript.
Keywords
Point 5: lines 25 – 26. The keyword (Malus domestica Borkh) is not in the title of the article or in the abstract. it must be added or removed from the keywords. Done.
- Please add the study area in Keywords. Done.
Introduction
The introduction can be improved including more references, and checked the English grammar, sentence framing and lengthy sentences and modified throughout the manuscript.
Point 6: line 106. It is necessary to write the fall name of the figure 1, the same for figure 4 (line 243) for the figure 9 (line 383). Done.
Materials and method
4.1 The study area:
Point 7: Line106. The figures should be placed in the center, and the name of the figure should be written with the completed form (Figure 1). Done.
Point 8: From lines 115 to 120: You talk in this paragraph about the climate of the area and the precipitation without mention the references. Please add the relevant references for the information presented. Done. Reference was added. 15. Del Pozo and Del Canto (1999).
Point 9: From lines 121 to 131: Same remark for this paragraph (References!!). Done. Reference was added.
Point 10: Line 136: you are talking about texture analysis in accordance with the international system for three soil without mentioned the reference of the international system. We agree. Reference is added in text.
Point 11: Line 156: It is necessary to write the fall name of the equation 1. Done.
Point 12: Line 178: same remark for equation 3. Done.
Point 13: Line 183: Same remark for equation 4. Done.
Point 14: From lines 163 to 175: All equations number should be mentioned in the text. Done.
Point 15: The line 244: The statistical Analysis: you should mention the reference form previous works. Done. Reference was added. 21. Jeelani et al. (2018).
Results and Discussion
Point 16: Line 283: It is necessary to write the fall name of the figure 4. Done.
Point 17: The authors presented in lines 283 to 285’’ when no water was applied in either treatment in the 2009-2010 season due to the Earthquake of February 27, 2010’’. The authors need to mention the reference of the origin study. Done. Reference was added: 22. ECLAC (2010).
Point 18: From 318 to 328: Please rephrase this paragraph. Done. We rewrite this paragraph.
Point 19: From 448 to 469: the authors should be improved to discuss how the findings of this study support or criticize the findings or arguments of previous studies. Done. We add a new paragraph and two new references: Naor et al. [30] and Mpelasoka et al. [31].
Point 20: Figure 5 (T1(a), T2(d); T1(b), T2(e)): please define the X axis. Same remark for the figure 7 and 8. Done.
- Finally, the English language used needs editing throughout with a moderate level of change required. This manuscript was reviewed by a native English speaker and professional editor.
Round 2
Reviewer 2 Report
First of all, I would like to thank the authors for their scientific efforts. After checking the authors response, I think, this article can be accepted after a minor revision. The authors must add more significant references in the Introduction and improve the language level of the manuscript.
Author Response
We add more significant references in the Introduction and removed or replaced non-relevant or hard-to-find references.
- Line 59: a short paragraph related with apple and water scarcity is added, given the relevance of this paper (Zhong etal., 2019).
-Line 70-76: these four new references are related with the above paragraph.
In fact, Naor [11] demonstrated the importance of crop load and irrigation relationships on apples; Francaviglia et al. [12] evaluated the effect of partial rootzone drying irrigation on two apple cultivars under Mediterranean conditions; Du et al. [13] studied alternate partial root-zone irrigation and water use efficiency relationships; and Liao et al. [14] analyzed the combination of different kind of mulching and irrigation deficit in an apple commercial orchard. In the Central Valley of Chile, Lecaros et al. [15] evaluated…
A professional editor, native English speaker, edited the manuscript.
