Influence of the Plant Training System on Yield and Nut Traits of European Hazelnut (Corylus avellana L.) Cultivar Nocchione
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe manuscript deals with the evaluation of training system on yield and basic physiological properties of hazelnuts. In general, the paper is well written, but it has some flaws that need to be corrected. The details are listed below:
Abstract:
Shorten the background. Focus on the results of the study. Indicate some values or % changes of examined parameters between training systems. Add further perspectives of the study. Do not repeat the text from the Introduction.
L13 and L61: countries such as USA
Introduction:
Indicate health benefits of hazelnuts in general. They are rich in amino acids, phenolic acids, and vitamins. For this purpose refer to https://doi.org/10.1016/j.foodchem.2024.140222
L93-98: clarify the aim of this study
Materials and Methods:
L170: how mold occurrence was evaluated?
Results:
L245: rephrase this statement because in current form it seems that in treatment C the highest growth occurred
L335: letters of statistical significance are missing in Table 2
Discussion:
Discussion is long, but not effective. Compare your own results with other studies and different training systems
Conclusions:
Do not include the aim of the study and references in the Conclusions. Briefly summarize, but not repeat the results
Author Response
Response to Editor and Reviewers’ comments - Ref. Ms. ID Agronomy-3425952
We present the revised manuscript after revisions made according to reviewers' requests. All responses to comments by individual Reviewer are listed below.
Our changes to the manuscript are in track changes mode.
Reviewer#1
Comments and Suggestions for Authors
The manuscript deals with the evaluation of training system on yield and basic physiological properties of hazelnuts. In general, the paper is well written, but it has some flaws that need to be corrected. The details are listed below:
Abstract:
Shorten the background. Focus on the results of the study. Indicate some values or % changes of examined parameters between training systems. Add further perspectives of the study. Do not repeat the text from the Introduction.
As suggested by Reviewer, the abstract has been modified by shortening the background and eliminating excessive details. Also, some details about the results and the further perspectives of the study.
L13 and L61: countries such as USA
Done.
Introduction:
Indicate health benefits of hazelnuts in general. They are rich in amino acids, phenolic acids, and vitamins. For this purpose, refer to https://doi.org/10.1016/j.foodchem.2024.140222
As proposed by the Referee, We added the following sentence and references (lines 51-53):
“In the last few decades, the nutritional properties of hazelnuts and their health benefits related to the richness of high-value fatty acids and natural antioxidants, have been emphasized, with the aim to promote their consumption [2–4].”
[2] Richardson, D.G., (1997). The health benefits of heating hazelnuts: implications for blood lipid profile, coronary heart disease and cancer risks, Acta Hortic., 445 (1997) 295–300. https://doi.org/10.17660/ActaHortic.1997.445.39
[3] Alasalvar, C., Karamac, M., Amarowizc, R., and Shahidi, F., (2006). Antioxidant and radical activities in extracts of hazelnut kernel (Corylus avellana L.) and hazelnut leafy cover. J. Agric. Food Chem., 54, 4826–4832. https://doi.org/10.1021/jf0601259
[4] Łozowicka, B., Kaczynski, P., Iwaniuk, P., Rutkowska, E, Socha, K, Orywal, K, Farhan, J.A., and Perkowski, M., (2024). Nutritional compounds and risk assessment of mycotoxins in ecological and conventional nuts. Food Chemistry, 458, 140222. https://doi.org/10.1016/j.foodchem.2024.140222
L93-98: clarify the aim of this study
As requested by the Referee, we changed the last sentence in the introduction section as follows:
“…., a trial has been established in central Italy with the aim to test the agronomic behavior of hazelnut plants of the cultivar Nocchione trained and pruned with three different training systems (two shrub versions, one sapling) to drive the choice of the best plant training system for future hazelnut plantations in HD approach, still poorly investigated.”
Materials and Methods:
L170: how mold occurrence was evaluated?
Mold incidence, as other defects, was evaluated during nut and kernel traits evaluation, expressed as percentage of the whole pool of nut samples yearly collected by each hazelnut plant submitted to shaping and pruning treatment, according to the standardized approach used in the breeding program of hazelnut carried out in Oregon State University. Results are reported in table 2.
Results:
L245: rephrase this statement because in current form it seems that in treatment C the highest growth occurred
We thank the Referee for the suggestion. We have clarified the sentence as follows, highlighting in total and relative plant growth when necessary.
“Among the multi-stemmed shrub training systems, treatment C showed the highest total values, represented by a larger number of branches per plant, while for treatment A (regular four-stemmed bush), intermediate values of TCSA were noted. Treatment A was characterized by the highest relative vegetative growth, increasing from 40.33 ± 2.63 cm2 in 2019 to 106.03 ± 2.36 cm2 in 2023, with a percentage increase of +162.91%, unlike treatment B (+139.39%) and control (+112.33%), that overall showed lower vigor.”
L335: letters of statistical significance are missing in Table 2
As proposed by Referee we have applied the z-test on normalized data to compare the influence of treatments for each research-year. Then, letters of statistical significance were added to Table 2 when necessary, and the related result paragraph has been improved accordingly. Furthermore, in the paragraph 2.5 (statistical analysis) the following sentence has been added:
“Furthermore, to assess the effect of shaping and pruning treatment on the incidence of hazelnut defects, the z-test was applied to compare the percentage incidence of the individual defect per research year.”
Discussion:
Discussion is long, but not effective. Compare your own results with other studies and different training systems.
As requested by the Referee and by the other ones, we improved the discussion section accordingly and comparing our findings with other studies available in literature, and following listed:
Me, G., Valentini, N., Caviglione, M., Lovisolo, C., (2005). Effect of shade on flowering and yield for two different hazelnut training systems. Acta Hortic., 686, 187-192. https://doi.org/10.17660/ActaHortic.2005.686.25
Tous, J., Romero, A., Plana, J., (2005). Comparison of two training prunings on 'Negret' and 'Gironell' hazelnut cultivars. Acta Hortic., 686, 243-246. https://doi.org/10.17660/ActaHortic.2005.686.32
Beyhan, N., (2007). Effects of planting density on yield and quality characteristics of hazelnut (cv. Palaz) in a hedgerow training system. Canadian Journal of Plant Science, 87 (3), 595-597. https://doi.org/10.4141/P05-064
Pannico, A., Cirillo, C., Giaccone, M., Scognamiglio, P., Romano, R., Caporaso, N., Sacchi, R., Basile, B., (2017). Fruit Position within the Canopy Affects Kernel Lipid Composition of Hazelnuts. J. Sci. Food Agric., 97, 4790-4799. https://doi.org/10.1002/jsfa.8348
Granata, M.U., Catoni, R., Bracco, F., (2021). The role of two different training systems in affecting carbon sequestration capability in hazelnut orchards. Energ. Ecol. Environ., 6 (4), 285-291. https://doi.org/10.1007/s40974-020-00202-1
Conclusions:
Do not include the aim of the study and references in the Conclusions. Briefly summarize but not repeat the results.
As proposed by the Referee we deleted the first sentence in the section and removed the references, with the only exception for Biocca et al., 2024, that in our point of view is highly pertinent in the section. Furthermore, the section has been also improved according to the suggestions of referee 3.
Reviewer 2 Report
Comments and Suggestions for Authors1. Please be sure that the abstract and the conclusions section not only summarize the key findings of the paper but also explain the specific ways in which this manuscript fundamentally advances the field relative to prior literature.
2. Please present a strong case for how this paper is a major advance. This needs to be done in the manuscript itself, not just in the response to review comments.
3. Please supplement the Latin scientific name in the title.
4. A list of the most important abbreviations should be given at the abstract to make the manuscript clearer.
5. The authors should add correct hypothesis and correlate with objective clearly.
6. Please include a quantitative description of the main research findings in the abstract.
7. Please merge lines 80-92 into a single paragraph.
8. Please supplement the research hypotheses in the last paragraph of the introduction, and discuss the hypotheses in the discussion section.
9. Please supplement the results of the variance analysis in Figure 7.
10.Please incorporate published relevant research findings into the discussion and engage in a thorough exploration of the topic.
11.Please do not cite references in the results any more. Meanwhile, summarize the existing research results and condense the results into a short passage.
Author Response
Reviewer#2
Comments and Suggestions for Authors
- Please be sure that the abstract and the conclusions section not only summarize the key findings of the paper but also explain the specific ways in which this manuscript fundamentally advances the field relative to prior literature.
We thank the Referee 2. The abstract has been revised to concisely present the main findings, including Treatment A’s superiority in yield and kernel quality within an HD system, also highlighting the evidence of the suitability of the four-stem shrub system in HD hazelnut cultivation, to address challenges in sustainable intensification. Furthermore, the section of conclusions has been improved as suggested.
- Please present a strong case for how this paper is a major advance. This needs to be done in the manuscript itself, not just in response to review comments.
According to the Referee’s request, we modified the proper sentence in the abstract as follows:
“In order to drive the current enlargement of hazelnut cultivation, attempts in designing high density (HD) and more occasionally super-high density (SHD) hazelnut orchards are on-going, although these are poorly explored in terms of suitable plant training systems, such that sometimes multi-stemmed plant shapes are used, otherwise single-trunk solutions are adopted.”
Furthermore, We modified the last sentence of the Introduction section as follows:
“In order to explore new hazelnut planting and training solutions focused on sustainable intensification, defined as the transformation of agricultural systems to increase production per unit without harming the environment [6], a trial has been established in central Italy with the aim to test the agronomic behaviour of hazelnut plants of the cultivar Nocchione trained and pruned with three different training systems (two shrub versions, one sapling) to drive the choice of the best plant training system for future hazelnut plantations in HD approach, still poorly investigated.”
- Please supplement the Latin scientific name in the title.
As suggested by the Referee we added the Latin scientific name in the title, deleting it by the keywords, where the following one has been added: “High density planting”
- A list of the most important abbreviations should be given at the abstract to make the manuscript clearer.
As proposed by the Referee, we added the most relevant abbreviations in the abstract.
- The authors should add correct hypothesis and correlate with objective clearly.
As proposed by the Referee, we changed the abstract accordingly.
- Please include a quantitative description of the main research findings in the abstract.
As proposed by the Referee, we improved the abstract accordingly.
- Please merge lines 80-92 into a single paragraph.
As suggested by the Referee, we merged the two paragraphs included in Lines 80-92.
- Please supplement the research hypotheses in the last paragraph of the introduction and discuss the hypotheses in the discussion section.
As suggested by the Referee, we changed the last paragraph of introduction as follows:
“In order to explore new hazelnut planting and training solutions focused on sustainable intensification, defined as the transformation of agricultural systems to increase production per unit without harming the environment [6], a trial has been established in central Italy with the aim to test the agronomic behaviour of hazelnut plants of the cultivar Nocchione trained and pruned with three different training systems (two shrub versions, one sapling) to drive the choice of the best plant training system for future hazelnut plantations in HD approach, still poorly investigated”
Furthermore, we improved the discussion section accordingly, and comparing our findings to other available literature on the topic.
- Please supplement the results of the variance analysis in Figure 7.
We thank the Referee for the suggestion. As described in the figure caption 7, no significant differences were observed among the treatments from the interaction of treatment x year.
- Please incorporate published relevant research findings into the discussion and engage in a thorough exploration of the topic.
We thank the Referee for the suggestion. We improved the section accordingly comparing our findings with the following references, the only available ones on the topic (together with those already mentioned in the first version of the manuscript), which is confirmed to be poorly investigated.
Listed below the added references cited to improve the discussion section of the manuscript through findings comparison.
Me, G., Valentini, N., Caviglione, M., Lovisolo, C., (2005). Effect of shade on flowering and yield for two different hazelnut training systems. Acta Hortic., 686, 187-192. https://doi.org/10.17660/ActaHortic.2005.686.25
Tous, J., Romero, A., Plana, J., (2005). Comparison of two training prunings on 'Negret' and 'Gironell' hazelnut cultivars. Acta Hortic., 686, 243-246. https://doi.org/10.17660/ActaHortic.2005.686.32
Beyhan, N., (2007). Effects of planting density on yield and quality characteristics of hazelnut (cv. Palaz) in a hedgerow training system. Canadian Journal of Plant Science, 87 (3), 595-597. https://doi.org/10.4141/P05-064
Pannico, A., Cirillo, C., Giaccone, M., Scognamiglio, P., Romano, R., Caporaso, N., Sacchi, R., Basile, B., (2017). Fruit Position within the Canopy Affects Kernel Lipid Composition of Hazelnuts. J. Sci. Food Agric., 97, 4790-4799. https://doi.org/10.1002/jsfa.8348
Granata, M.U., Catoni, R., Bracco, F., (2021). The role of two different training systems in affecting carbon sequestration capability in hazelnut orchards. Energ. Ecol. Environ., 6 (4), 285-291. https://doi.org/10.1007/s40974-020-00202-1
11.Please do not cite references in the results any more. Meanwhile, summarize the existing research results and condense the
As suggested by the Referee, we have deleted the references by results section and condensed the results into short passage, when possible (also according to the other reviewers’ request).
Reviewer 3 Report
Comments and Suggestions for AuthorsThis paper studied the effects of three different tree-like training systems on the yield and nut characteristics of Corylus europaea under high planting density (HD). Although hazelnut planting has a long history, there is relatively little research on different tree shapes under HD planting mode, especially on hazelnut in Europe.However, at present, the following problems still exist in the abstract, literature review, interpretation of results and other aspects of the paper, which are suggested to be revised:
Comment 1: In the abstract part, it may be necessary to simplify the sentence structure, avoid repetition, and clarify the research purpose and highlight the research results.
Comment 2:In the introduction, it may be necessary to adjust the paragraph structure, and the paragraph on the expansion of hazelnut planting area (paragraph 4) and the paragraph on the advantages and disadvantages of multi-stem cluster tree (paragraph 5) can be merged.The definition and advantages of HD planting mode can be supplemented in paragraph 6.
Comment 3: In the Material and Methods section, it may be necessary to explain the environmental factors such as soil type and climatic conditions of the experimental field; The randomized block design, the number of plants and the number of repetitions in each treatment group were used in the experiment. This information is crucial for understanding the research results.
Comment 4: At the same time, the pruning methods of each tree can be described in more detail, including pruning time, pruning tools, pruning degree and so on.
Comment 5: In explaining the statistical analysis method, we can explain the reasons for choosing two-way analysis of variance (ANOVA) and explain the significance of interaction. At the same time, the reasons for multiple comparisons using Fisher test are further explained.
Comment 6: In the Results section, the processing group and year represented by the legend can be clearly stated in the title of the chart, and error lines can be added to compare the differences between different processing groups more intuitively.
Comment 7: In the Discussion part,The mechanism behind the research results can be discussed more, for example, why the multi-stem cluster tree can improve the yield and nut quality of hazelnut.
Comment 8: At the same time, the research results can be combined with the practical application of hazelnut planting, for example, to explain what guidance and suggestions the research results can provide for hazelnut growers.
Comment 9: It can be emphasized that the advantages of conventional four-trunk cluster tree in HD planting mode. At the same time, we can compare the effects of more varieties and different tree shapes under different environmental conditions, and study the effects of different tree shapes on the occurrence and control of pests and diseases.
Author Response
Reviewer#3
Comments and Suggestions for Authors
This paper studied the effects of three different tree-like training systems on the yield and nut characteristics of Corylus europaea under high planting density (HD). Although hazelnut planting has a long history, there is relatively little research on different tree shapes under HD planting mode, especially on hazelnut in Europe. However, at present, the following problems still exist in the abstract, literature review, interpretation of results and other aspects of the paper, which are suggested to be revised:
We thank Referee 3 for the suggestions. Below are reported the revisions made described point by point.
Comment 1: In the abstract part, it may be necessary to simplify the sentence structure, avoid repetition, and clarify the research purpose and highlight the research results.
As requested, the abstract has been rephrased and the research purpose and primary findings are explicitly stated, with numerical results to support conclusions.
Comment 2: In the introduction, it may be necessary to adjust the paragraph structure, and the paragraph on the expansion of hazelnut planting area (paragraph 4) and the paragraph on the advantages and disadvantages of multi-stem cluster tree (paragraph 5) can be merged. The definition and advantages of HD planting mode can be supplemented in paragraph 6.
As proposed by the Referee, we rearranged the Introduction section accordingly.
Comment 3: In the Material and Methods section, it may be necessary to explain the environmental factors such as soil type and climatic conditions of the experimental field; The randomized block design, the number of plants and the number of repetitions in each treatment group were used in the experiment. This information is crucial for understanding the research results.
We thank the Referee for her/his suggestion.
As reported in the first and second paragraphs of Material and Methods section all the requested information are already reported as follows:
“The hazelnut orchard was established in 2016, using a planting layout of 4.5 m x 3.0 m, with a density of 740 plants ha-1. The orchard was equipped with a subirrigation system with two drip wings per row, placed 30 cm deep into the ground and 80 cm from the row on each side. The experimental orchard was characterized by a loamy-clay soil with acid-ic pH (5.6), low-medium organic matter content (1.4%), low C/N ratio (8) promoting fast mineralization processes, medium cation exchange capacity (17.5 meq), low assimilable phosphorus, high potassium concentration and slightly unbalanced Mg/K ratio due to an excess of K content.”
“To test the most suitable hazelnut plant shape in HD orchards, 10 shrubs per shaping treatment were pruned at their third leaf in field. The selected plants planted using mechanical transplanting [18], had never been pruned until the implementation of the trial, except for the manual removal of suckers, which started from the second year after planting, as suggested in literature [10].
Three different plant shaping were adopted, corresponding to three different pruning approaches for plant training on a total of 30 even-aged plants selected on two contiguous rows on a representative portion of the orchard.
During February 2016 the pruning treatments were applied as follows: in treatment A ten plants were trained as regular four-stemmed bush (Figure 1); in treatment B ten plants were trained as single trunk sapling form (Figure 2); in treatment C (control) ten plants were trained as traditional multi-stemmed shrub (Figure 3), a plant shaping very common in hazelnut orchards in central Italy.”
Furthermore, according to the Referee proposal, we added the following sentences in the first paragraph of the same section to detail the climatic condition of the experimental trial:
“According to Köppen classification, the climate of the study area corresponds to CSa: Hot and dry summer Mediterranean climate, with the coldest month averaging above 0°C and at least one month's average temperature above 22°C and at least four months averaging above 10°C. Furthermore, the average precipitation in the study area was 757 mm per year as reported in the available data source of the Italian Institution for Environmental Protection and Research (http://www.scia.isprambiente.it, accessed on January, 20th)”
Comment 4: At the same time, the pruning methods of each tree can be described in more detail, including pruning time, pruning tools, pruning degree and so on.
We thank the Referee for the suggestion.
As already reported in paragraph 2.2 many of the requested info were given in the manuscript. Furthermore, for more complete description of the pruning methods adopted, the following sentences were moved in the paragraph from results and discussion section (paragraph 3.1):
“For symmetric four-stemmed bush (treatment A) and multi-stemmed bush (treatment C) vigorous and properly oriented shoots were selected to grow for the bush formation, whereas in the following years the plant canopy was maintained free from excess branches and shoots by operating with a light annual pruning and annual sucker removal. In order to train plants as single trunk sapling form (treatment B) the most vigorous and upright shoot of the shrub was selected and cut 80-90 cm above the ground at the beginning of the third year, maintaining in the following years the sapling-shape by removing excess branches in the tree canopy and annual sucker removal.”
Moreover, the following sentence has been added in the same paragraph 2.2. “All annual cutting operations conducted during the trial were carried out using pneumatic scissors and manual saws.”
Comment 5: In explaining the statistical analysis method, we can explain the reasons for choosing two-way analysis of variance (ANOVA) and explain the significance of interaction. At the same time, the reasons for multiple comparisons using Fisher test are further explained.
As requested by the Referee, we have improved paragraph 2.5 as follows:
“All the data recorded over the five-year study period were subjected to statistical analysis through the Rstudio software (version 2024.09.0+375). Before statistical analysis, the input data were analyzed through Shapiro-Wilks’s test, in order to identify their distribution (p-value ≤ 0.05). The identification of normal data distribution allowed it to proceed with a parametric statistical approach. A two-way ANOVA was applied for all input, with exception of nut defects, to find out the influence exerted on the analyzed parameters by the factor “year,” “cultivar,” and their interaction. Consequently, Fisher's test was performed to determine significance levels and assign letters for homogeneous groups, considering a p-value ≤ 0.01. The values expressed as percentages, before being analyzed, were subjected to angular transformation according to the formula (x + 0.5)/2.
Furthermore, to assess the effect of shaping and pruning treatment on the incidence of hazelnut defects, the z-test was applied to compare the percentage incidence of the individual defect per research year.“
Comment 6: In the Results section, the processing group and year represented by the legend can be clearly stated in the title of the chart, and error lines can be added to compare the differences between different processing groups more intuitively.
We thank the Referee for the suggestions. For more clarity we improved statistical analysis section adding the following sentence: ”A two-way ANOVA was applied for all input, with exception of nut defects, to find out the influence exerted on the analyzed parameters by the factor “year,” “cultivar,” and their interaction”. Furthermore, we prefer to maintain the standard deviations lines in the charts since it is generally most relevant for any bar graph in which groups, treatments, etc. are explicitly or implicitly compared, and is usually the one needed for bar graphs in biology. Average standard error makes more sense for technical replications of a single measurement of a particular phenomenon in physical units.
Comment 7: In the Discussion part, the mechanism behind the research results can be discussed more, for example, why the multi-stem cluster tree can improve the yield and nut quality of hazelnut.
As requested by the Referee, we added in the section the following sentence accordingly:
“Between the two shrub shapes, the four-trunk cluster training system has shown a steady increase in production over the years as well as greater stability in the high technological nut traits. This is probably due to the plant architecture in treatment A, providing a more uniform canopy distribution and consequent less shading within plant and between contiguous ones, which is reflected in a more uniform light interception and a consequent better distribution of photosynthates, as confirmed in the literature [29,30]”
Comment 8: At the same time, the research results can be combined with the practical application of hazelnut planting, for example, to explain what guidance and suggestions the research results can provide for hazelnut growers.
The sentence proposed in comment 7 highlighting the effectiveness of treatment A is also valid to drive the growers in choosing the plant training system. Guidelines in pruning approaches are also given in improved way in the Materials and Methods section.
Comment 9: It can be emphasized that the advantages of conventional four-trunk cluster tree in HD planting mode. At the same time, we can compare the effects of more varieties and different tree shapes under different environmental conditions and study the effects of different tree shapes on the occurrence and control of pests and diseases.
As suggested by the Referee, we improved the section, accordingly, adding the following sentence at the end of the section:
“Finally, this four-trunk cluster training system in HD planting should be explored on hazelnut varieties with different vigor, in different environments and in different planting distances to confirm its sustainable application under different growing conditions.”
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe Authors have corrected the paper. I have no more comments
Author Response
We thank the reviewer for her/his positive comment
Reviewer 2 Report
Comments and Suggestions for Authors1. Please supplement the results of the one-way analysis of variance in Figure 7 and denote differences using letters.
Author Response
As requested by the reviewer, We submitted the YE data to one-way ANOVA to evaluate separately the effect of pruning treatment and research-year. As this last effect only showed significant differences, We added the figure 8 in the section 3.4 describing the yearly YE expressed as mean of pruning treatments.
Furthermore, we improved the sections 2.5 and 3.4 accordingly
Reviewer 3 Report
Comments and Suggestions for AuthorsACCEPT
Author Response
We thank the reviewer for her/his positive comment
