The Effect of Polyethylene Film and Polypropylene Non-Woven Fabric Cover on Cobs Parameters and Nutritional Value of Two Sweet Maize (Zea mays L. var. saccharata Bailey) Hybrids

Round 1

Reviewer 1 Report

Overall, a very interesting study on how different plastic films could either accelerate sweet maize development to harvest, yield, and/or nutritional quality. I hope my following comments are helpful.

While your title implies that your focus is on the effect that plastic covers have on cobs and (as I read it), also the effect of the covers on the nutritional value of two sweet maize hybrids, there is only one vague sentence referring to the covers:

‘The yield increase as a result of the applied covers was higher after 24 sowing at a later date.’

In the abstract also, there’s the objective of evaluating the response of two sweet maize to five different covers and sowing date. Yet the final line of the abstract is confirming a correlation of AGDD and dependence of grain quality on dry matter content in the grain, which didn’t seem to relate to your title.

M&M

For your PE foils, how perforated were they? Can you please add a # perforations, or X of 1 mm diameter holes per square m?

How thick were the PE and PP foils?

Where were the temperature loggers located vertically? Ground-level, top of plants, mid-plant level, constant height?

Would it be possible to list the sowing dates and the average cover removal dates per type, per year?

Please use the translation of deciton or decitonne instead of decyton.

Figure 1 needs units on the Y and YY axes.

Line 253: With the later sowing date, there was no significant difference in the vegetation period when you take into account your data variation (± amounts). Suggestion to use the word numerically or nominally to describe non-significant changes.

Line 254: Again, your film cover overall differences were also non-significant. As suggested above, highlight that the covers nominally helped advance the plants to being harvestable.

Figure 2a: Please spell out your legend words and include units. It’s confusing that you use (I assume) the word No to mean number in some places, then spell out number in other places.

Figure 2b: Same – what’s No grain per cob? An empty, aborted, or unpollinated cob. I don’t think that’s what you meant.

Lines 282-287: Aha! I was looking for these sentences to be in the abstract, as they are more in line with your title and objective statements than some other sentences in the abstract. Also, Line 293-294 are some nice findings that relate to both the covers and the sowing date on yield that could have been in the abstract. (or use 299). Same for the Sucrose and carotenoids. Highlight the changes that your treatments did on these parameters, not the givens of hybrid differences.

Table 5 needs zeaxanthin in English.

Figure 5 Please avoid using yellow as data markers on the white page background. There are suggestions on the web as colors to pair up or avoid for color-blind people, too.

Line 376: do you mean 952.9 AGDD?

Author Response

Wrocław 05.03.2021

Józef Sowiński

Institute of Agroecology and Plant Production

Wroclaw University of Environmental and Life Science

Ms. Silvia-Valentina Ureche

Assistant Editor

We are thankful for insightful comments and chance to revise, strengthen, and resubmit the manuscript entitled:"The effect of polyethylene film and polypropylene non-woven fabric cover on cobs parameters and nutritional value of two sweet maize (Zea mays L. var. saccharata Bailey) hybrids"by Katarzyna Adamczewska-Sowińska, Józef Sowiński, MirosławAnioł, Piotr Ochodzki, Roman Warzecha.

We addressed all Reviewers and Editors' comments. Below is the point-by-point response to each comment and description of changes in the manuscript.

Reviewer 1

Question - comments:

Overall, a very interesting study on how different plastic films could either accelerate sweet maize development to harvest, yield, and/or nutritional quality. I hope my following comments are helpful.

While your title implies that your focus is on the effect that plastic covers have on cobs and (as I read it), also the effect of the covers on the nutritional value of two sweet maize hybrids, there is only one vague sentence referring to the covers

‘The yield increase as a result of the applied covers was higher after 24 sowing at a later date.’

Response:

The results showed that in temperate climates, very early sowing of maize despite cover applied does not provide optimal conditions for growth and high yield of maize.  The yield increase at the earlier date compared to the control was of 2.0-20.3% while at the later date it was of 16.0-36.7%. The sentence quoted by the reviewer was included in the original text based on the results obtained.

Question - comments:

In the abstract also, there’s the objective of evaluating the response of two sweet maize to five different covers and sowing date. Yet the final line of the abstract is confirming a correlation of AGDD and dependence of grain quality on dry matter content in the grain, which didn’t seem to relate to your title.

Response:

This is due to the cause-effect relationship. Total AGDD depended on all factors and especially covers and it varied among hybrids. On the other hand, dry matter content of grain was correlated with AGDD (Fig. 2). Whereas the grain quality evaluation showed the dependence of some sugars and carotenoids content on dry matter content. In our opinion, it is not in contradiction with the title of the article.

Question - comments:

For your PE foils, how perforated were they? Can you please add a # perforations, or X of 1 mm diameter holes per square m?

Response:

Added:  perforation of 100 holes per 1 m², each with a diameter of 10 mm.

Question - comments:

How thick were the PE and PP foils?

Response:

Added: PE film of 0.2 mm thickness and PP unwoven fabric of 17 g m^-2 were used

Question - comments:

Where were the temperature loggers located vertically? Ground-level, top of plants, mid-plant level, constant height?

Response:

Changed and precise:

During the initial period of maize vegetation, soil temperature was measured at a depth of 5 cm using a digital thermometer DT-34. After removing the covers, air temperature was measured using a Temp Logger AZ8828 placed 2 m above the soil surface.

Question - comments:

Would it be possible to list the sowing dates and the average cover removal dates per type, per year?

Response:

Added: 1^st sowing date  was  on April 18, 15, and 8 in 2012, 2013, and 2014, respectively. In all the years, the 2^nd sowing date was on the same day (April 25). The other information was provided in the publication Adamczewska-Sowińska, Sowiński 2020 [24]. The information was supplemented in the text.

Question - comments:

Please use the translation of deciton or decitonne instead of decyton.

Response:

Corrected

Question - comments:

Figure 1 needs units on the Y and YY axes.

Response:

Corrected

Question - comments:

Line 253: With the later sowing date, there was no significant difference in the vegetation period when you take into account your data variation (± amounts). Suggestion to use the word numerically or nominally to describe non-significant changes.

Response:

Corrected – line 291

Question - comments:

Line 254: Again, your film cover overall differences were also non-significant. As suggested above, highlight that the covers nominally helped advance the plants to being harvestable.

Response:

Corrected – lines 292-293

Question - comments:

Figure 2a: Please spell out your legend words and include units. It’s confusing that you use (I assume) the word No to mean number in some places, then spell out number in other places.

Response:

Corrected

Question - comments:

Figure 2b: Same – what’s No grain per cob? An empty, aborted, or unpollinated cob. I don’t think that’s what you meant.

Response:

Corrected: No means number of grain per cobs

Question - comments:

Lines 282-287: Aha! I was looking for these sentences to be in the abstract, as they are more in line with your title and objective statements than some other sentences in the abstract. Also,

Line 293-294 are some nice findings that relate to both the covers and the sowing date on yield that could have been in the abstract. (or use 299). Same for the Sucrose and carotenoids. Highlight the changes that your treatments did on these parameters, not the givens of hybrid differences.

Response:

Following sentences added in abstract:

The use of maize cover at the beginning of growth (PE and PER) significantly influenced the number of rows while PE and PEG increased the number of grains per cob. Covering maize sown at a later date with polyethylene film and non-woven fabric ensured better production effects than using such covers after earlier sowing.

Question - comments:

Table 5 needs zeaxanthin in English.

Response:

Thank you. Corrected.

Question - comments:

Figure 5 Please avoid using yellow as data markers on the white page background. There are suggestions on the web as colors to pair up or avoid for color-blind people, too.

Response:

Changed

Question - comments:

Line 376: do you mean 952.9 AGDD?

Response:

Changed. Thank you.

Reviewer 2 Report

This manuscript is interesting and potentially acceptable for publication.
However, a few changes should be made before publication.

Comments for author File: Comments.pdf

Author Response

Wrocław 05.03.2021

Józef Sowiński

Institute of Agroecology and Plant Production

Wroclaw University of Environmental and Life Science

Ms. Silvia-Valentina Ureche

Assistant Editor

We are thankful for insightful comments and chance to revise, strengthen, and resubmit the manuscript entitled:"The effect of polyethylene film and polypropylene non-woven fabric cover on cobs parameters and nutritional value of two sweet maize (Zea mays L. var. saccharata Bailey) hybrids"by Katarzyna Adamczewska-Sowińska, Józef Sowiński, MirosławAnioł, Piotr Ochodzki, Roman Warzecha.

We addressed all Reviewers and Editors' comments. Below is the point-by-point response to each comment and description of changes in the manuscript.

Reviewer 2

Review report:

The effect of polyethylene film and polypropylene non-woven fabric cover on cobs parameters and nutritional value of two sweet maize (Zea mays L. var. saccharataBailey) hybrids Katarzyna Adamczewska-Sowińska, Józef Sowiński,*, MirosławAnioł, Piotr Ochodzki and Roman Warzecha This manuscript is interesting and potentially acceptable for publication. However, a few changes should be made before publication. Specific comments are listed below

Question - comments:

Page 1 The Abstract does not indicate where the experiment was conducted. A summary of the materials and methods used is missing. Irrigation or non-irrigation system? Rephrase and complete.

Response:

We added the following information in the abstract and materials and methods:  “at the Research and Didactic Station of the Department of Horticulture at Wroclaw University of Environmental and Life Sciences (51°19’06’’ N, 17°03’49’’ E)

and later  

with non-irrigation system

Question - comments:

Introduction: Page 2 line 61 Authors cited that there is no information in the literature on the effect of polyethylene and poly- propylene covers on carbohydrate content in kernels, but there are a lot of information about cover crops or organic mulch. In general, authors do not state what are the advantages of the chosen method of cultivation compared to previous ones in the production of sweet corn.

Response:

This is a different cultivation method than mulching with plastic films and organic mulches.

The answer also indicates what are the benefits of choosing this way of maize cultivation.

In the cultivation of maize, low tunnels, 40 cm high, of foil or non-woven fabric were used at the beginning of its growth. The plants were thus protected from unfavorable thermal conditions, such as frost. This is important especially during seed germination and seedling emergence. Such covers make plant development continuous and faster than in cultivation without them. The entire article deals with the effect of short-term covering of maize on the quantity and quality of its yield. The authors do not share the opinion that the use of plant covers and the use of mulches are similar treatments that should be compared to each other. This was not the subject of research and the article compares cultivation with the use of covers and traditional cultivation - without covers.

Question - comments:

Material and Methods Prepare the substrate in low tunnel are missing, other cultural practices during the vegetation…

Response:

Added information about soil condtions.

The experiment was conducted on soil, degradated chernozems with a calcic level (FAO-WRB Gleyic Calcic Chernozems soil) on medium clay.

and response to crop management practice

No treatment was performed in the tunnels until the structures were dismantled.

Question - comments:

The statistical methods used in the paper are not described in detail.

Response:

Changed and are now described in more detail.

Question - comments:

Results Page 6 line 237 authors cited: The average air temperature in all years of the study was higher than the multiannual average. They should show data on a multi-year average!

Response:

Figure 1 modified

Question - comments:

Page 7 line 278 are missing full stop.

Response:

Corrected.

Question - comments:

Very well done and clear graphics (2,3,4 and 5), but not properly commented! What does the regression equation, i.e regression parameters, show us?

Response:

We have supplemented the research results by adding correlation coefficients.

Question - comments:

In Table 3, a statistical analysis was performed for cob yield but not for the percentage of marketable cob yield. Why?

Response:

Explanation added:

The percentage of marketable cob yield was calculated as the share of marketable yield in the total yield. These values were provided as averages for the treatments (without replications) and were not subjected to statistical analysis.

Question - comments:

Cobs yield and morphological parameters take up a lot of space in the results subchapter, but not in the discussion!

Response:

Added comments

Cob morphological traits varied among the hybrids under study. Signet F1 hybrid had a significantly higher number of rows per cob, while Rustler F1 had a significantly higher number of grains per row and per cob. The type of cover significantly differentiated only the number of rows. A study by Ghimire et al. (2020) showed a significant effect of film type on morphological traits such as cob length, diameter, grain size and grain formation.

Question - comments:

Authors concluded that maize, especially hybrids with high sugar content, are characterized by high sensitivity to unfavorable habitat conditions, especially during the early growing season. How to solve this problem while keeping the mentioned hybrids?

Question - comments:

Response:

Added comments

 It is recommended that sh2 varieties should be grown later after the spring chill has passed. When soil temperature reaches the optimum value (>10°C), growth of sh2 maize is normal. In temperate climates, sowing should be delayed or covers should be used. For an early, good quality yield of sh2 sweet corn, cultivation should be done according to the recommendations of this study. The transparent perforated film provided the best grow-ing conditions and the highest yield of early sown sweet maize.

Question - comments:

The experimentation seems adequately conducted, and the results confirm previous studies. However, some parts of the manuscript, including Materials and methods, are not sufficiently detailed, and the Results section needs to be profoundly improved.

Response:

The Materials and Methods and Results chapters have been corrected according to the reviewer's remarks.