Response of Warm Season Turf Grasses to Combined Cold and Salinity Stress under Foliar Applying Organic and Inorganic Amendments

Round 1

Reviewer 1 Report

The scientific idea behind the study can be acceptable. Backgrounds and objectives are well constructed, well written, and clear; however, there are minor deficiencies that need to be incorporated before publishing. 

Material and method: have you applied one-way analysis of variance (ANOVA), please mention in detail.

Results: Most of the figures shown high standard error (SE) please check it carefully.

Discussion and introduction section should have more recent citations.

Minor grammatical changes, please check the English of the whole article carefully to eliminate any grammatical error.

Regards

Author Response

Reviewer 1#

Comments and Suggestions for Authors

The scientific idea behind the study can be acceptable. Backgrounds and objectives are well constructed, well written, and clear; however, there are minor deficiencies that need to be incorporated before publishing.

Response: many thanks for your comment and encouragement!

Material and method: have you applied one-way analysis of variance (ANOVA), please mention in detail.

Response: many thanks for your comment!

Thanks, yes, one-way and was added to the statistical analyses!

Results: Most of the figures shown high standard error (SE) please check it carefully.

Response: many thanks for your comment!

Yes, we noticed that in some figures, thanks! We checked the data and everything is correct. This may be back to our work carried in the open field NOT in the Lab. Working in the Lab means everything under control and small the errors! Here it also included the variation due to the two seasons.

Discussion and introduction section should have more recent citations.

Response: many thanks for your comment!

Ok, we added more recent citations in both sections of the discussion and introduction, thanks!!

Agricultural production faces many stresses including abiotic and biotic stresses. These stresses have been ameliorated using many different organic materials (e.g., humic substances, organic matter, compost, etc.) and inorganic amendments (e.g., silicon sources, sulfuric compounds, selenium, etc.) (Feng et al. 2023). These amendments have distinguished role in supporting crop production under stressful conditions (Clemente et al. 2019). Concerning silicon, it is the second abundant element in the earth's crust, which could be found in the biological systems in the form of amorphous silica (Ahire et al. 2021). Silicon is considered a vital soil amendment to improve biotic/abiotic stresses resistance/tolerance in many plant species (Ahire et al. 2021). Silicon can improve production of many crops under different stresses such as water deficit (Xu et al. 2023), heavy metals toxicity (Jin et al. 2023), drought stress (Zahedi et al. 2023), and biotic stress (Gao et al. 2023). Regarding humic substances (mainly humic, fulvic and acids), they have a significant impact in promoting cultivated plants through stimulating plant nutrient uptake, phytohormone signaling, enzyme antioxidants, and photosynthetic efficiency and regulating reactive oxygen species (da Silva et al. 2022). Humic substances can promote plant growth and development under different stresses such as salinity (da Silva et al. 2022), soil remediation (Wang et al. 2023), drought and salinity stresses (Alsamadany 2022), and biotic stress (Faccin and Di Piero 2022). Concerning sulfur compounds, they have a vital role from different point of views like soil amendmentor or conditioner of salt-affected soils by via biological oxidation into sulfuric acid (Chen et al. 2023). Sulfur also is effective in remediating alkaline/sodic soil through decreasing soil pH and increasing sulfate anion (Liu et al. 2022).

Minor grammatical changes, please check the English of the whole article carefully to eliminate any grammatical error.

Response: many thanks for your comment!

The following grammatical changes are made:

• Line 29: added a comma before “and”
• Line 34: simplified the sentence by removing “these turfgrasses”
• Line 53: simplified the sentence by removing “leaf color” as it is included in “ turf quality”.
• Line 55: changed the sentence structure
• Line 63: changed to “stresses are” and simplified the sentence
• Line 72-74: removed part of the sentence
• Line 155: removed “and” before roots
• Line 170-171: Changed to “The scorings were done according to National Turfgrass Evaluation Program or NTEP [34].
• Line 405: added a comma before “and”
•  

Regards

Many thanks again!

Author Response File: Author Response.docx

Reviewer 2 Report

I would like to congratulate the authors for their efforts in this line of research that always requires complex field work. They have evaluated the effect of amendments on C4 grasslands by analyzing different crop parameters. These studies improve knowledge in this field, little studied, very present in our satiety and truly necessary for greater sustainability. However, some important drawbacks must be addressed to ensure that the manuscript reaches the expected quality of articles published in Horticulturae. Below, I include a series of comments intended to improve the quality of the manuscript:

1. In section 1, a good approach to the work is developed, proposing at the end an investigation that answers some questions and that would be more focused if they were listed in lines instead of being included as a paragraph.

2. In section 2.1, for a better definition of materials and test methods, the physical characterization of the soil should be completed a little more, indicating, if available, texture classification, agronomic parameters of percentage of organic matter and fertility (N-P-K).

3. In section 2.2, various details are given regarding maintenance in terms of irrigation and fertilization, but for a good concretion of the test, the program carried out in terms of annual fertilizer units N-P-K applied, the annual amount of irrigation used and quality should be indicated. , and may also include some data on mowing or other tasks carried out.

4. In section 3.1 there is a typo where it reflects Fig.1 should put Fig.2

5. In section 4, a more explanatory order and content can be organized in the proposed structure, since 4 paragraphs are developed that attend to the organizational scheme of the investigation described at the end of section 1. Introduction of 4 questions, we see that section 3 does not begin with the original question, and should generally be somewhat more in-depth, focusing on the field work done and justifying what was observed.

The first paragraph attends well to the discussion regarding the work carried out, missing developing it equally in the rest of the paragraphs, that is, specifying more in data and results found. The last paragraph is somewhat indeterminate, the question must be answered based on the measurements and data obtained in the essay, apart from reflecting what is already mentioned.

In the final part of paragraphs 2 and 3, the action of humic acids is commented and justified. Perhaps it would be convenient to raise all this in another paragraph and introduce this discussion as one more question to be incorporated at the end of section 1.

6. In section 5 the conclusions expressed are evident and well defined, they are clearly reflected in all the tables and figures resolved by the test, verifying that the simple control sample of seashore paspalum is dominant with respect to the tifway bermudagrass, (with the exception of in some measurement parameters of figure 2). Perhaps it would be interesting to focus and comment on the proportion of improvement, which is logically always present, of each species with respect to its control for each treatment applied, thus being able to have a line of behavior that allows for an objective comparison with respect to the different treatments and its different effects on them.

This type of work should always be completed by proposing more studies combining tested patterns, which is done and it is always necessary to continue investigating, but perhaps after addressing the aforementioned, a future line of research and work space to be followed can be further specified. to treatments, species or varieties with which, based on the results of the research, it is interesting to continue working, including evaluating varying maintenance guidelines, soil characterization, irrigation or fertilization.

Author Response

Reviewer 2#

Comments and Suggestions for Authors

I would like to congratulate the authors for their efforts in this line of research that always requires complex field work. They have evaluated the effect of amendments on C4 grasslands by analyzing different crop parameters. These studies improve knowledge in this field, little studied, very present in our satiety and truly necessary for greater sustainability. However, some important drawbacks must be addressed to ensure that the manuscript reaches the expected quality of articles published in Horticulturae. Below, I include a series of comments intended to improve the quality of the manuscript:

Response: many thanks for your comment and encouragements!

1. In section 1, a good approach to the work is developed, proposing at the end an investigation that answers some questions and that would be more focused if they were listed in lines instead of being included as a paragraph.

Response: many thanks for your comment!

Done, thanks!

2. In section 2.1, for a better definition of materials and test methods, the physical characterization of the soil should be completed a little more, indicating, if available, texture classification, agronomic parameters of percentage of organic matter and fertility (N-P-K).

Response: many thanks for your comment!

The used soil was a salt-affected soil. The soil texture (0 – 20 cm) was classified as clay, where the particle size distribution was 19,7% sand, 25,0% silt, and 55,3% clay, whereas soil salinity (EC), pH, and sodium adsorption ratio (SAR) were 4.49 dS m⁻¹, 8.65 and 19.0, respectively. Soil organic matter and soil cation exchange capacity (CEC) were 14.5 g kg^-1, and 40.5 cmol_c kg^-1 soil, whereas water table was at 90 cm from the soil surface. The available N, P, K were 30, 12, 185 mg kg^-1, respectively. The main soil moisture parameters were field capacity, wilting point, and available water (43.25, 23.11, and 20.14%, respectively. The previous soil parameters were determined according to Sparks et al. 1996 and Campbell (1998). Selected amendments were investigated in current study including organic (humic acid), and inorganic amendments (sources of sulfate and silica). Compost was applied to all area in 1^st November of each season at 10 m³ per feddan (2.38 kg m^-2). To reduce the surface tension of leaves, 0.1% Tween 20 was applied into the sprinkler system to avoid surface runoff.

3. In section 2.2, various details are given regarding maintenance in terms of irrigation and fertilization, but for a good concretion of the test, the program carried out in terms of annual fertilizer units N-P-K applied, the annual amount of irrigation used and quality should be indicated and may also include some data on mowing or other tasks carried out.

Response: many thanks for your comment!

The quality of irrigation water was non-saline fresh water, where the value of pH and EC were 7.71 and 225 ppm, respectively. The available N and P in irrigation water were 0.09 and 28 mg L^-1, respectively. Irrigation was performed according to the recommendations of the Ministry of Agriculture and Land Reclamation of Egypt. Turfgrass were mowed at a height of 3 cm using the appropriate mowing machine 2-3 times a week during the warm months of the year and from 0 to 1 time a week during the cold months throughout the experiment. The plants were sprinkled irrigation for 15 minutes three times a week and fertilized with NPK (20:20:20) once a week at rat of 1.5 g L^-1 through a sprinkler irrigation system.

4. In section 3.1 there is a typo where it reflects Fig.1 should put Fig.2

Response: many thanks for your comment!

Corrected, thanks!

5. In section 4, a more explanatory order and content can be organized in the proposed structure, since 4 paragraphs are developed that attend to the organizational scheme of the investigation described at the end of section 1. Introduction of 4 questions, we see that section 3 does not begin with the original question, and should generally be somewhat more in-depth, focusing on the field work done and justifying what was observed.

Response: many thanks for your comment!

Modified, Thanks!

We added the following part:

Concerning which source of silicon and its applied dose is the best to ameliorate the growth and quality of studied turfgrasses, it is not clear. The applied Si-sources have different impacts on studied parameters, which were significantly higher for many vegetative growth attributes, but no significant trend was observed in case of turf quality. For the nutrient content, there is no shar difference between silicon and diatomite treatments. Although many studies published on the impacts of different sources of silicon on cultivated plants under stress such as canola under water deficit (Valizadeh-rad et al. 2022), wheat under water deficit (Valizadeh-rad et al. 2022), feverfew under drought (Esmaili et al. 2022), but very rare studies on turfgrass.

The first paragraph attends well to the discussion regarding the work carried out, missing developing it equally in the rest of the paragraphs, that is, specifying more in data and results found. The last paragraph is somewhat indeterminate, the question must be answered based on the measurements and data obtained in the essay, apart from reflecting what is already mentioned.

Response: many thanks for your comment! We suggested some open questions to be answered in the future in the last paragraph!

We added more in the last paragraph.

In the final part of paragraphs 2 and 3, the action of humic acids is commented and justified. Perhaps it would be convenient to raise all this in another paragraph and introduce this discussion as one more question to be incorporated at the end of section 1.

Response: many thanks for your comment!

We already added one paragraph concerning this amendment through the very recent literature reviews. As well as a figure (NO. 6) for more details to improve the MS.

6. In section 5 the conclusions expressed are evident and well defined, they are clearly reflected in all the tables and figures resolved by the test, verifying that the simple control sample of seashore paspalum is dominant with respect to the tifway bermudagrass, (with the exception of in some measurement parameters of figure 2). Perhaps it would be interesting to focus and comment on the proportion of improvement, which is logically always present, of each species with respect to its control for each treatment applied, thus being able to have a line of behavior that allows for an objective comparison with respect to the different treatments and its different effects on them.

Response: many thanks for your so nice comment! Done, thanks!

This type of work should always be completed by proposing more studies combining tested patterns, which is done and it is always necessary to continue investigating, but perhaps after addressing the aforementioned, a future line of research and work space to be followed can be further specified. to treatments, species or varieties with which, based on the results of the research, it is interesting to continue working, including evaluating varying maintenance guidelines, soil characterization, irrigation or fertilization.

Response: many thanks for your comment!

This part was in the M and M section regarding the soil characterization, program of fertilization and irrigation also were added to revised MS as follow:

The used soil was a salt-affected soil. The soil texture (0 – 20 cm) was classified as clay, where the particle size distribution was 19,7% sand, 25,0% silt, and 55,3% clay, whereas soil salinity (EC), pH, and sodium adsorption ratio (SAR) were 4.49 dS m⁻¹, 8.65 and 19.0, respectively. Soil organic matter and soil cation exchange capacity (CEC) were 14.5 g kg^-1, and 40.5 cmol_c kg^-1 soil, whereas water table was at 90 cm from the soil surface. The available N, P, K were 30, 12, 185 mg kg^-1, respectively. The main soil moisture parameters were field capacity, wilting point, and available water (43.25, 23.11, and 20.14%, respectively. The previous soil parameters were determined according to Sparks et al. 1996 [18] and Campbell (1998). Selected amendments were investigated in current study including organic (humic acid), and inorganic amendments (sources of sulfate and silica). Compost was applied to all area in 1^st November of each season at 10 m³ per feddan (2.38 kg m^-2). To reduce the surface tension of leaves, 0.1% Tween 20 was applied into the sprinkler system to avoid surface runoff.

The quality of irrigation water was non-saline fresh water, where the value of pH and EC were 7.71 and 225 ppm, respectively. The available N and P in irrigation water were 0.09 and 28 mg L^-1, respectively. Irrigation was performed according to the recommendations of the Ministry of Agriculture and Land Reclamation of Egypt. Turfgrass were mowed at a height of 3 cm using the appropriate mowing machine 2-3 times a week during the warm months of the year and from 0 to 1 time a week during the cold months throughout the experiment. The plants were sprinkled irrigation for 15 minutes three times a week and fertilized with NPK (20:20:20) once a week at rat of 1.5 g L^-1 through a sprinkler irrigation system. The main temperature during the study was recorded for the maximum and minimum (Figure 1).

Author Response File: Author Response.docx

Reviewer 3 Report

Dear Authors,

Your manuscript is a valuable contribution of high scientific output. The study of turf grasses under combined cold and salinity stress is up to date.

I propose you to do some transformation of the text, give explanations and make a few corrections. The details are presented herewith below.

Major comments

Lines 74-75
…turfgrass is more tolerant to combined cold and salinity stress…

Please provide temperature and salinity data and characterize corresponding state of plants during experiment.

Lines 87-88

The used soil was salt-affected soil, where the soil salinity, pH and sodium adsorption ration (SAR) were 4.5 dS m-1, 8.6 and 19, respectively.

Soil salinity data are not sufficient because the soil salinity changes depending on the soil moisture while salt content remains the same.

You did not characterize the soil water content which is decisive for the plant growth and amendments application result.

Minor comments

Line 90

…mentioned university…

This is a new subsection. Please name the university here.

Line 156
Table 2.

What the letters abc after the digital data mean?

Author Response

Reviewer 3#

Comments and Suggestions for Authors

Dear Authors,

Your manuscript is a valuable contribution of high scientific output. The study of turf grasses under combined cold and salinity stress is up to date.

I propose you to do some transformation of the text, give explanations and make a few corrections. The details are presented herewith below.

Response: thanks for your comment!

Major comments

Lines 74-75

…turfgrass is more tolerant to combined cold and salinity stress…

Please provide temperature and salinity data and characterize corresponding state of plants during experiment.

Response: thanks for your comment!

The max. and min. temperature were recorded at the Horticulture Research Station, Sakha, Kafr El-Sheikh (Figure 1). This part added to the revise Ms.

To be honest, we did not measure the soil salinity regularly, because we have published many articles on this salt-affected soil and we thought that this will be repetition by measuring the soil salinity before staring the experiment especially we carried the springer irrigation system, which allow us to focus on the plants more! Yes, you are right, the fluctuation of soil salinity is important parameter.

May be this plant species are relative tolerant to soil salinity, and this the reason!

We will take this important parameter in mind in the future, thank!

As added in the M and M more details concerning soil, irrigation and fertilization programs, which already we used during this study!

Some published articles:

Omara, Alaa El-Dein, Mahmoud Aiad, Essam G. Abo-Elela, Hassan El-Ramady and Megahed M. Amer (2022). Significant Use of Molasses and Foliar Application of Ca(NO3)2 on Improving of Some Soil Properties and Yield of Rice under Salt Affected Soils. Env. Biodiv. Soil Security, Vol. 6, pp: 285 – 297.

El-Ramady, H, Salah E.-D. Faizy, Megahed M. Amer, Tamer Elsakhawy, Alaa El-Dein Omara, Yahya Eid, Eric C. Brevik (2022). Management of Salt-Affected Soils: A Photographic Mini-Review. Env. Biodiv. Soil Security, Vol. 6, pp: 61 – 79.

Hafez EM, Osman HS, El-Razek UAA, Elbagory M, Omara AE-D, Eid MA, Gowayed SM (2021). Foliar-Applied Potassium Silicate Coupled with Plant GrowthPromoting Rhizobacteria Improves Growth, Physiology, Nutrient Uptake and Productivity of Faba Bean (Vicia faba L.) Irrigated with Saline Water in Salt-Affected Soil. Plants, 10, 894. https://doi.org/10.3390/plants10050894

Lines 87-88

The used soil was salt-affected soil, where the soil salinity, pH and sodium adsorption ration (SAR) were 4.5 dS m-1, 8.6 and 19, respectively.

Soil salinity data are not sufficient because the soil salinity changes depending on the soil moisture while salt content remains the same.

You did not characterize the soil water content which is decisive for the plant growth and amendments application result.

Response: thanks for your comment!

We added a part on the soil water content, water quality, which already used in the study beside the figure of fluctuation in temperature (max. and min.) during the study!

We totally agree with your comment. The soil water pattern under sprinkler irrigation system may be useful in our study, thanks! We will follow this advice in our next work!

Minor comments

Line 90

…mentioned university…

This is a new subsection. Please name the university here.

Response: thanks for your comment! Done, thanks!

Line 156

Table 2.

What the letters abc after the digital data mean?

Response: thanks for your comment! corrected, thanks!

Means within column having the same letters are not significantly different according to the Duncan's Multiple Range Test (at p <0.05)

Author Response File: Author Response.docx