Effects of Cascara Cherry and Other Coffee Litter Mulching on Soil Properties, Photosynthesis, and Water Use Efficiency of Coffea Canephora Pierre ex A. Froehner cv. Reyan No.1 Seedling

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Coffee is among the most consumed beverage groups in the world. In this study, the effectiveness of mulch and water use in coffee seedlings was evaluated. Today, drought is among the important stress conditions. Due to increasing global warming, drought has posed a significant threat to plant species. Therefore, this study will make significant contributions to the literature. In this respect, it is an original work. The study is well discussed with previous studies. The references used are sufficient. It needs revisions at some points. To summarize these:

 

Add Latin in the article title. 

Also, remove one of the words coffee used twice in the article title.

More numerical data, methods, etc. should be added to the summary.

Entrance

In the first paragraph of the introduction section, parameters such as the herbal characteristics of the coffee, important producing countries, production values, etc. should be added.

Again, a few sentences can be written about mulching. (importance etc).

The characteristics of the variety used in the material and method section can be written in a few sentences.

 

The table formats used in the study are very clear and understandable. However, I cannot say the same for the figures. The figures are written in small font letters and are not understandable. Please review the figures. Or you made it bigger.

The correlation analysis given in Figure 4 makes significant contributions to the study. By making this analysis, the authors added depth to the conflict. However, the picture cannot be understood because it is quite small. Please enlarge it.

 

 

The conclusion section should be rewritten. It is written very little. Mention the important results of the study here.

 

  In addition, "It is an important deficiency that the article is based on single-year data. These studies should be planned on a multi-year basis, taking into account the effects of climate etc. in field trials." These sentences should be detailed in the study.

 

I congratulate the authors for their work. I believe that the quality of the article will increase after the revisions.

Author Response

 

Thanks for your valuable suggestion, the author has corrected the annotation error in SE. As the reviewer viewpoint, the response of soil properties and microenvironment to coffee waste mulch treatment is almost negligible, except for soil temperature and soil-available potassium. Both coffee cascara and litter mulch did significantly reduce soil temperature, while the soil-available potassium under cascara and litter mulch treatment was significantly higher than the control and cascara mulch treatment, and the soil-available potassium under litter mulch treatment also showed an increasing trend when compared to the control. Therefore, the soil-available potassium content under litter mulch treatment was significantly higher than that under the control. Please see line 206.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The work is clear and the topic is pertinent to coffee producers. Below are some questions about the work that are not clear and are pertinent questions that occur in similar experiments in Brazilian coffee production areas.

 

1. lthough the article mentions the use of Coffea canephora Pierre ex Froehner cv. Reyan No.1, it would be useful to provide a brief rationale for choosing this specific variety over others available.

2. The article mentions that all experimental procedures were conducted consistently, but it would be important to provide more details on how other environmental variables, such as temperature and humidity, were controlled to ensure the validity of the results.

3. The article focuses on the effects of litter and pericarp mulching on soil properties and coffee growth, but it could delve into explaining the underlying physiological mechanisms that lead to these effects. For example, how exactly does coffee pericarp affect soil temperature and why does that influence photosynthesis?

4. Did the study consider the economic viability of using coffee litter and pericarp mulching in terms of cost-effectiveness for farmers?

5. Are there any practical limitations or challenges in implementing litter and pericarp mulching on a commercial scale that were not addressed in the study?

Author Response

The work is clear and the topic is pertinent to coffee producers. Below are some questions about the work that are not clear and are pertinent questions that occur in similar experiments in Brazilian coffee production areas.

Thank you for the reviewer's recognition of this study. During the actual cultivation process of coffee, the author found that Robista coffee from Southeast Asian countries such as China and Vietnam is commonly grown under mulching cultivation. Therefore, this is an interesting scientific question to explore the impact of this cultivation method on coffee plant growth and yield.

 

1. Lthough the article mentions the use of Coffea canephora Pierre ex Froehner cv. Reyan No.1, it would be useful to provide a brief rationale for choosing this specific variety over others available.

Thanks for your valuable suggestion, the author has added the reason for choosing this variety to the Experimental materials section of Materials and Methods. Please see line 134-138.

 

 

2. The article mentions that all experimental procedures were conducted consistently, but it would be important to provide more details on how other environmental variables, such as temperature and humidity, were controlled to ensure the validity of the results.

Thanks for your valuable suggestion. This study conducted a field experiment. During the experiment, the author ensured consistency in the management plan for coffee seedlings under all treatments, including the frequency, amount, and time of fertilization and irrigation. Due to the experimental site being located in a coffee plantation, there is no significant heterogeneity in soil properties, climate, and management plans. The only difference between different treatments is the type of coffee waste. Therefore, the author did not intentionally control other environmental variables. The differences in environmental variables between different treatments during the experimental process should be attributed to the different waste mulch. Please see line 148-150.

 

3. The article focuses on the effects of litter and pericarp mulching on soil properties and coffee growth, but it could delve into explaining the underlying physiological mechanisms that lead to these effects. For example, how exactly does coffee pericarp affect soil temperature and why does that influence photosynthesis?

Thanks for your valuable suggestion. The author add the possible reasons for coffee peel mulching to reduce soil temperature to the discussion section as “The stacking of coffee peel layers has a honeycomb like structure, which could change the surface airflow dynamics, reduce the soil temperature of the coffee plantation”, please see line 332-335; The author has revised some of the discussion on the physiological mechanisms by which the decrease in soil temperature affects the photosynthesis of coffee plants as “ On the one hand, as a shallow-rooted plant, coffee is suitable for growing at 22.0 to 28.4 ℃, and it is particularly sensitive to variations in soil temperature. Higher temperature will inhibit coffee plant photosynthesis by reducing the enzyme activity of plant roots or leaves, when the soil temperature is higher than the suitable photosynthetic temperature for coffee plants”, please see line 326-330; The mechanism of promoting photosynthesis in coffee plants by increasing soil potassium content has been added to the next section, please see line 336-351.

 

4. Did the study consider the economic viability of using coffee litter and pericarp mulching in terms of cost-effectiveness for farmers?

Thanks for your valuable suggestion, the author and research team first conducted extensive investigation on the cultivation mode of coffee, and found that most Robusta coffee plantations adopt the cover cultivation mode. Therefore, the author's research team believes that using coffee litter and pericarp instead of traditional mulch has development potential in the coffee production process. Secondly, coffee pericarp is a byproduct of the coffee processing process, which is usually discarded or piled up for fermentation and maturation to produce organic fertilizer. However, the fermentation process requires transportation costs, rental space, and labor input, combined with the market situation and cost control risks of organic fertilizer, making the coffee pericarp organic fertilizer is not cost-effective from an economic perspective. Finally, the research team used coffee waste directly return to the field, which is currently one of the lowest cost solutions for utilizing coffee pericarp. But the author also believes that with the improvement of coffee pericarp utilization technology, there will be better application methods for the utilization of coffee pericarp. The relevant description is in the second paragraph of the introduction, please see 62-70.

 

5. Are there any practical limitations or challenges in implementing litter and pericarp mulching on a commercial scale that were not addressed in the study?

Thanks for your valuable suggestion. This study is a field control experiment using coffee peel and litter cover, and has not yet been commercially implemented on a large scale. The practical limitations and challenges mainly include the following three parts: First, the ripening of coffee cherries varies seasonally, and the typical coffee fruiting period is 3-6 months. Due to the fact that coffee cherries are not centrally matured, the total quality of coffee fruits in each batch of the processing plant is relatively low, making it difficult to form a scale advantage and thereby reducing utilization costs. Second, mature coffee cherries and leaf litter may contain some pests, such as fruit beetles and branch beetles. Directly returning coffee waste to the field is not conducive to the prevention and control of pests and diseases in coffee plantations. Third, this study is only a short-term mulch experiment. It is worth observing whether long-term mulch of coffee waste will enhance its allelopathic effect on its own plants and cause self toxicity in coffee plant. In addition, this study used coffee seedlings and has not yet started producing coffee cherries. Therefore, this experiment will continue to be conducted to observe the impact of long-term coffee waste mulch on the quality and yield of coffee cherries in coffee plant.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors,

In general, the manuscript is adequate to results presented in this paper; the structure of the work is clear and looks complete. After reading the paper, it is clear that the authors have experience in agriculture experiments, concerning on mulching procedures. It is well known that mulch helps improve soil moisture and prevents plants from drying out too quickly, reduce soil erosion and soil compaction, maintain optimal soil temperatures by creating a barrier from the heat and cold. Additionally, increase soil nutrition as it decomposes by improving soil structure, thus providing better drainage and better use of nutrients and reduce weeds that can steal nutrients from your plants. Mulching could potentially serve the purpose by reducing soil evaporation, conserving moisture, controlling soil temperature, reducing weed growth, and improving microbial activities. Additionally, mulches could provide economical, aesthetic, and environmental advantages to agriculture and landscape. It’s a pity that authors did not study old literature, where you can find some information on mulching of coffee plants (”The Mulching of Coffea Arabica”, the article received 03 May 1945, Published online: 18 Dec 2015). There are other study on this subject in literature. However, in this study, the authors used coffee pericarp and litter as a mulch material for covering soil around coffee plant, and studied the influence of this process on soil moisture content, temperature and bulk density, as well as, soil organic meter and increase of area leaf and respiration and photosynthesis, carbon use efficiency.

The authors used coffee cherry pericarp and litter as a mulch material for covering soil around coffee plant; however, it is not only pericarp. It is dried material as waste, that it coming after coffee fruit processing, which is named cascara. Cascara, which means husk, peel or skin in Spanish, is the dried skins of coffee cherries. These pulped skins consist of all layers such as pulp (mesocarp), pectin layer (mucilage), parchment (endocarp) silver skin (epidermis), remain and are collected after the beans have been removed from the cherries. More information of cascara uses you can find in the paper: “Risk Assessment of Coffee Cherry (Cascara) Fruit Products for Flour Replacement and Other Alternative Food Uses”.

 See my comments below, which most of them will be helpful in a future study:

 1.      Lines: 2-3 – The title is not precision. I propose: “Effects of Cascara Cherry Mulching and other coffee Mulching Liter on Soil Properties and Photosynthesis and Water Use Efficiency of Coffee Canephora Seedling”. It is very important to indicate species, because Arabica and Canephora have not only different resistant to disease, but have different root system implicating various water intake.

2.      Lines: 35-36 – I agree, that coffee is the most commercialized food products, including developing countries, however it should be indicate, that the coffee quality depend to region, altitude, as well as, factors such species, cultivar and number important parameters of processing at harvest and after (roasting, grinding and brewing). In this place you should cited paper concerning on some of this problems; eg. I also suggested some papers that can complete and improve literature review concerning on methods of quality estimation of coffee bean: “How to identify roast defects in coffee beans based on the volatile compound profile”, or “Effect of the roasting level on the content of bioactive and aromatic compounds in Arabica coffee beans”.

3.      Lines: 72-74 – The cited paper concerning on influence of nitrogen fertigation on wheat seed, and does not agree to the sentence: “Leaf carbon use efficiency (CUE) is an important indicator of plant carbon balance, which reflects the carbon assimilation ability of coffee plant by considering photosynthesis and respiration”.

4.      Lines: 76-79 – Similar as in previous remark, the literature cited concerning forest and cacao, and does not agree to the sentence: “Previous studies indicated that environmental factors, such as precipitation, temperature, light, and soil nutrients, have significant impact on photosynthesis, respiration and transpiration of coffee leaves photosynthesis, respiration and transpiration of coffee leaves”. You can write only, “… should have significance ….”

5.      Line 112 – in this line authors indicated what species of coffee is studied (Cofea Canephora, cv. Reyan No.1.), that species must be included in title, as I said earlier.

6.      Lines 136, 137 and 139 – Is the same nitrogen? Abbreviation (SAN) is used the same: alkaline dissolved nitrogen (SAN)  and alkali-hydrolyzed nitrogen (SAN)

7.      Line 112 – What’s mean “the fourth layer of leaves”

8.      Line 137 – It should be: coffee plant photosynthesis, not coffee photosynthesis

9.      Lines: 188-189 – Table 1- Looking on results presented in Table 1, it is easy to conclude, that there is no significant differences for all studied combination of mulch, and there are not any visible influence of mulch on soil properties and microclimate surrounding soil. Standard errors are higher than differences between CK, L, P and LP for all studied properties. However, error for soil available phosphorus for combination CK should be 10.41 instead 1041.  

Nomenclature concerning with mulching is correct, and the manuscript is written clear and in understandable language for reader. I recommend it to be published in corrected form after minor revision.

Comments on the Quality of English Language

The manuscript is written clear and in understandable language for reader. Nomenclature concerning with mulching is correct, however, I recommend it to be published after minor correction..

 

 

Author Response

Coffee is among the most consumed beverage groups in the world. In this study, the effectiveness of mulch and water use in coffee seedlings was evaluated. Today, drought is among the important stress conditions. Due to increasing global warming, drought has posed a significant threat to plant species. Therefore, this study will make significant contributions to the literature. In this respect, it is an original work. The study is well discussed with previous studies. The references used are sufficient. It needs revisions at some points. To summarize these:

Thank you to the reviewer for their positive feedback on this study. The author has made detailed revisions to the manuscript based on the reviewer's comments, and the modified parts have been marked in the new manuscript, please review it.

 

1. Add Latin in the article title.Also, remove one of the words coffee used twice in the article title.

Thanks for your valuable suggestion, the authors revised the title to “Effects of Cascara Cherry and Other Coffee litter Mulching on Soil Properties and Photosynthesis and Water Use Efficiency of Coffee Canephora Seedling” based on suggestions, Please see line 2-4 in the new manuscript.

 

2. More numerical data, methods, etc. should be added to the summary.

Thanks for your valuable suggestion, authors added the description of experimental treatment and main measurement indicators in the abstract. Meanwhile, the results of soil microenvironment have been added and the description of some results has been modified in the new manuscript. Please see line 16-38.

 

3. In the first paragraph of the introduction section, parameters such as the herbal characteristics of the coffee, important producing countries, production values, etc. should be added.Again, a few sentences can be written about mulching. (importance etc).

Thanks for your valuable suggestion, the authors carefully rewrote the first paragraph of the introduction, adding descriptions related to coffee quality characteristics of coffee, important producing countries, and production value in new manuscript. The description of the covering is placed in the second paragraph of the introduction. Author believes that such modifications may be more accord to the logical order. Please see line 44-70.

 

4. The characteristics of the variety used in the material and method section can be written in a few sentences.

Thanks for your valuable suggestion, the author has added the reason for choosing this variety to the Experimental materials section of Materials and Methods. Please see line 134-138.

 

5. The table formats used in the study are very clear and understandable. However, I cannot say the same for the figures. The figures are written in small font letters and are not understandable. Please review the figures. Or you made it bigger.

Thanks for your valuable suggestion, author has remade the figures and tables, and enlarged the font letters in the figures. Please see figures and tables in the new manuscript.

 

6. The correlation analysis given in Figure 4 makes significant contributions to the study. By making this analysis, the authors added depth to the conflict. However, the picture cannot be understood because it is quite small. Please enlarge it.

Sorry for the author's negligence. The author has remade this figure and enlarge the font letters to ensure that readers can read it clearly. Please see line 276.

 

7. The conclusion section should be rewritten. It is written very little. Mention the important results of the study here.

Thanks for your valuable suggestion, author has made detailed revisions to the conclusion and added a section on the main results. The new conclusion is revised as: Both cascara cherry and litter mulch do not affect agronomic traits of coffee seedlings, soil properties and microenvironment except significantly reducing soil temperature and increasing soil available potassium content in this study. Coffee cascara mulching had a positive impact on the photosynthesis of coffee seedling by improving the soil microenvironment rather than increasing nutrient content conditions, although the water use efficiency and carbon use efficiency of coffee seedlings are not sensitive to the coffee cascara mulching cultivation. The promotion effect of coffee cascara mulching on the photosynthetic and growth indices of coffee seedlings is significantly higher than that of coffee litter mulching or mixed mulching treatment after comprehensive evaluation in this study. Coffee cascara mulching is conductive to promote the growth of seedlings, cost saving and efficiency improvement in the coffee production process, which is beneficial in coffee cultivation practices. Please see line 419-430.

 

8. In addition, "It is an important deficiency that the article is based on single-year data. These studies should be planned on a multi-year basis, taking into account the effects of climate etc. in field trials." These sentences should be detailed in the study.

Thanks for your valuable suggestion, author added relevant descriptions at the end of the discussion as “Furthermore, it is an important deficiency that this study is based on single-year data. This study has been planned based on a multi-years of experience, and indicators such as climate factors, soil physicochemical properties, agronomic traits of coffee plants, photosynthetic physiology, yield, and quality of coffee cherries will be continuously monitored in future research to clarify the impact of long-term coffee waste mulch on coffee plants”. Please see line 412-417.

Author Response File: Author Response.pdf