Evaluation of Potato Varieties Grown in Hydroponics for Phosphorus Use Efficiency

Round 1

Reviewer 1 Report

The authors attempted to revise their manuscript and while not all my concerns were addressed, the manuscript cohesion and flow are improved. The last point that the authors should address the overestimation of the effects of the TCP treatment. The results of the study suggest only a minor effect of this treatment in P uptake and P usage efficiency. The authors should revise the manuscript (especially the conclusions part) accordingly. 

Author Response

The authors attempted to revise their manuscript and while not all my concerns were addressed, the manuscript cohesion and flow are improved. The last point that the authors should address the overestimation of the effects of the TCP treatment. The results of the study suggest only a minor effect of this treatment in P uptake and P usage efficiency. The authors should revise the manuscript (especially the conclusions part) accordingly. 

Response:

L358-374, Revised accordingly.

TCP was used because we believe TCP can differentiate elite and semi-elite potato genotypes in P utilization efficiency (Figure 3) but the low P treatment was not able to tell the difference in P utilization efficiency between the genotypes.

Reviewer 2 Report

In the manuscript “Evaluation of Potato Varieties Grown in Hydroponics for Phosphorus Use Efficiency“ authors Wei Chieh Lee, Lincoln Zotarelli, Diane L. Rowland and Guodong Liu discussed about variability in P uptake, mobilization, and utilization of TCP with the typical P-efficient and P-inefficient potato varieties and test a HS method that combines different traits into one index evaluating potato varieties for P-use efficiency.

Abstract OK

Key words; OK

Introduction

L 58 s 20 oC write °C

L 76-77 The following statement is not clear: If a cultivar increases Ca uptake when grown in a solution with TCP, the cultivar will 76 likely result in increasing P bioavailability and having more bioavailable P for this cultivar, leading to enhanced P-use efficiency.

L 92(Lee et al., 2013) and (2) test a HS method that combines different traits. Number for reference?

Materials and Methods

Clear and well explained

Results and Discussion

First paragraph fits more to the Material and Method section

L182 The following statement is not clear: This can be explained by the genotypic differences in P uptake or accumulation (Fig. 2), P utilization (Fig. 3).

L 218 The following statement is not clear In the control, the P supplied was NaH2PO4 and all bioavailable.

L 225 The following statement is not clear: ‘Red LaSoda’ was the lowest among the three varieties tested.

L 237-238 Phosphorus uptake from soil solution is the first step for plants to utilize the essential nutrient element. The uptake efficiency of phosphorus is highly associate with the active uptake surface area of the root system to the nutrient element. Reference is missing.

L 248 The following statement is not clear: Very fortunately, there is much biodiversity in P uptake of potato varieties.

L 257. The following statement is not clear: This much P fertilizer was applied approximately a month before planting, the fertilizer applied might be mainly fixed by aluminum in the aluminum rich soil.

L 277. The following statement is not clear: This ‘Red LaSoda’ was the smallest, whereas ‘Harley Blackwell’ was the greatest

Conclusions

L 322 The following statement is not clear: Based on these individual phenotypic responses, it was difficult to differentiate the varieties.

Specific comments

I would like to highlight the hard and complex work of the authors. I think that is has merit for publication. Generally speaking, the text is clearly written, and clearly describes experiments. I suggest more discussion with the literature data.

My suggestions: minor revision

Author Response

In the manuscript “Evaluation of Potato Varieties Grown in Hydroponics for Phosphorus Use Efficiency“ authors Wei Chieh Lee, Lincoln Zotarelli, Diane L. Rowland and Guodong Liu discussed about variability in P uptake, mobilization, and utilization of TCP with the typical P-efficient and P-inefficient potato varieties and test a HS method that combines different traits into one index evaluating potato varieties for P-use efficiency.

Abstract OK

Key words; OK

Introduction

L 58 s 20 oC write °C

Response:

L58, Revised accordingly.

L 76-77 The following statement is not clear: If a cultivar increases Ca uptake when grown in a solution with TCP, the cultivar will 76 likely result in increasing P bioavailability and having more bioavailable P for this cultivar, leading to enhanced P-use efficiency.

Response:

L76-84, Revised as needed: six lines were added and the sentences were revised.

L 92(Lee et al., 2013) and (2) test a HS method that combines different traits. Number for reference?

Response:

L99, Revised accordingly.

Materials and Methods

Clear and well explained

Results and Discussion

First paragraph fits more to the Material and Method section

Response:

L102-112, the paragraph is moved to the M&M section.

L182 The following statement is not clear: This can be explained by the genotypic differences in P uptake or accumulation (Fig. 2), P utilization (Fig. 3).

Response:

L199-201, Revised accordingly.

L 218 The following statement is not clear In the control, the P supplied was NaH2PO4 and all bioavailable.

Response:

L236, Revised accordingly.

L 225 The following statement is not clear: ‘Red LaSoda’ was the lowest among the three varieties tested.

Response:

L224-225, Revised accordingly.

L 237-238 Phosphorus uptake from soil solution is the first step for plants to utilize the essential nutrient element. The uptake efficiency of phosphorus is highly associate with the active uptake surface area of the root system to the nutrient element. Reference is missing.

Response:

L258, Revised accordingly.

L 248 The following statement is not clear: Very fortunately, there is much biodiversity in P uptake of potato varieties.

Response:

L268-269, Revised accordingly.

L 257. The following statement is not clear: This much P fertilizer was applied approximately a month before planting, the fertilizer applied might be mainly fixed by aluminum in the aluminum rich soil.

Response:

L278-281, Revised accordingly.

L 277. The following statement is not clear: This ‘Red LaSoda’ was the smallest, whereas ‘Harley Blackwell’ was the greatest

Response:

L299, Revised accordingly.

Conclusions

L 322 The following statement is not clear: Based on these individual phenotypic responses, it was difficult to differentiate the varieties.

Response:

L362-374, Revised accordingly.

Specific comments

I would like to highlight the hard and complex work of the authors. I think that is has merit for publication. Generally speaking, the text is clearly written, and clearly describes experiments. I suggest more discussion with the literature data.

Response:

L333-348, truly appreciate all the valuable comments from our anonymous reviewers. More discussion is added accordingly.

My suggestions: minor revision

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

In the manuscript “Evaluation of Potato Varieties Grown in Hydroponics for Phosphorus Use Efficiency« authors Wei Chieh Lee, Lincoln Zotarelli, Diane L. Rowland, Guodong Liu compared variability in P uptake, mobilization, and utilization of TCP with the typical P-efficient and P-inefficient varieties.

Abstract is OK. Please check decimal points

Key words Are OK.

Introduction

Is informative.

Agricultural demand of P for crop production is expected to increase 51% to 86% by the year 2030 Full stop is missing

P-use efficiency of potato is defined as tuber yield increase per unit of P-fertilizer applied and is most related to cultivar, P source, P application time, P replacement, the quantity of P application, soil, rainfall/irrigation, crop management, etc. Please add the reference

…in February and early March. (4) put semicolon

Materials and Methods

Clear and well explained

The seed pieces WERE grown in aeroponics in a modified

Results and Discussion

English is not clear: Root/shoot ratio was significantly (p < 0.05) in the low P and TCP treatments as compared to that in the control, across all three cultivars (Figure 4).

Ste statement is not clear: In the 1 mg L-1 P treatment, the P supplied was all available as well but was too low.

Paragraphs 3.2., 3.3. are without a single reference!

Specific comments

This is a nice compact study showed that each of the tested varieties of potato germplasm is different in P-use efficiency. I think that is has merit for publication. Generally speaking, the text is clearly written, and clearly describes experiments. However, in the Results and Discussion section I expect more discussion with the literature!

Reviewer 2 Report

The paper of Lee et al examines the effect of P availability on the growth of 3 potato genotypes. The topic of the article is suitable for Agriculture, however, some critical shortcomings prevent me from suggesting the acceptance of the manuscript. The authors should re-work their paper, add more data and re-submit it for a new evaluation.

Major (critical) points

• The format of the manuscript is not compatible with the Agriculture Journal guidelines.
• The experimental design is rather weak. Critical physiological aspects of plants, related directly to the quality and productivity should have been investigated (for example total protein, total sugar, and chlorophyll contents). Moreover, the authors at the beginning of the results/discussion part state that the availability of P from TCP is regulated by the Ca levels and this “system” is also genotype-dependent, the Ca levels of the plants of this experiment (at least as more interactions exist between the P uptake and the availability of other macro and micronutrients) is necessary for backing these statements.
• The discussion part should be separated from the results (again according to the Agriculture guidelines) and should be considerably reinforced, currently, almost no discussion exists, and the results/discussion part is actually a listing of the results of this experiment with some (scarce) comments by the authors.
• The presentation of figure 5 needs differentiation or the addition of the statistical analysis (typical for bar-chats).
• Some results (regarding the use of TCP) are discussed in length while no remarkable differences from the low P treatment ware found.

Minor points

• …There is a concern that the world P rock resources would be quickly depleted in decades [3] and the world would face a potential P crisis [4]. Recent estimates show that world P rock may not be run out soon [5]. However, the phosphate resources are limited, nonrenewable, and are gradually depleted due to increased use.

This statement is contradicting.

• …The objectives of this study were to: (1) compare variability in P uptake, mobilization, and utilization of TCP with the typical P-efficient and P-inefficient varieties selected…. The mobilization of P is not studied in depth (root, shoot, leaves).
• …Two seedlings were transplanted and grown in a 1750 mL plastic container filled
• with the above nutrient solution… Revise to 2 seedlings/container.
• ….In early May 2019, we did a field survey for another ongoing study….. This argument is problematic as only one variety is discussed in comparison to another variety not studied in this experiment.
• Table 1 must be transferred in the supplementary data of this paper