Intercropping of Cauliflower with Lettuce Is More Effective for Sustainable Fertilizer Management and Minimizing Environmental Risks

Round 1

Reviewer 1 Report

I have browsed the manuscript entitled “Intercropping of cauliflower and lettuce as influenced by nitrogen fertilization”. There are several questions need to be resolve.
1. The novelty aspects and its underlying concepts are not clear in this manuscript.

2.The results and discussion in the manuscript is too descriptive and much of them only literature was provided to support these mechanisms but no data.
3. Some conclusion was made, but not based on the study results. For example, “minimizing environmental risks”, “intercropping systems should be included for higher yield and income”. environmental risks and income were not evaluate in the manuscript.

4.Lack of soil physicochemical properties and elements analysis at different soil depths under Intercropping of cauliflower and lettuce.

Author Response

Dear Editor,

On behalf of all of the co-authors, I would like to thank the editor and the reviewers for careful reading, and constructive suggestions for our manuscript. According to comments from editor and reviewers, we comprehensively revised our manuscript.

We are looking forward to your feedback and further comments/suggestions are welcome.

The reviewers' comments are reproduced in black; our responses are detailed below in red:

 

RESPONSE TO REVIEWERS First of all, I would like to extend our gratitude to the anonymous reviewers for forwarding very constructive criticism of the MS and giving us an opportunity to improve the standard of the MS. We are glad to state that all suggestions forwarded by the reviewer have been incorporated in their entirety and none has been left unaddressed.

Reviewer 1

I have browsed the manuscript entitled “Intercropping of cauliflower and lettuce as influenced by nitrogen fertilization”. There are several questions need to be resolve.
1. The novelty aspects and its underlying concepts are not clear in this manuscript.

Response 1. You are quite right in your criticism. That's why we changed the article title to Intercropping of cauliflower with lettuce is more effectively for sustainable fertilizer management and minimizing environ-mental risks

2.The results and discussion in the manuscript is too descriptive and much of them only literature was provided to support these mechanisms but no data.

Response 2.

Results

Growth characteristics of cauliflower were significantly affected by nitrogen fertilization treatments whereas the effect of cropping treatments usually was nonsignificant (p>0.05) in yield and yield parameters (Table 2 and 3). A statistically significant (p<0.001) difference between plant weights in treatments was determined for both years. In both years, the highest plant weight was achieved as 1086.65 g plant^–1 (1^st year) and 1167.50 g plant^-1 (2^nd year) in the monocropping (MC) treatment when 240 kg ha^–1 nitrogen was applied. Intercropping did not significantly affect the plant weight, and 1082.55 g plant^–1 (1^st year) and 1157.83 g plant^–1 (2^nd year) plant weight was obtained in the intercropping (IC) treatment when 240 kg ha^–1 nitrogen was applied. Two years average plant weight value of the cauliflower for MC and IC treatment were 1127,01 g plant^–1 and 11120.19 g plant^–1 when 240 kg ha^–1 nitrogen was applied, respectively. Although plant weight decreased by 0.61% in IC system compared to MC for cauliflower, when IC system was used for the same total area and fertilizer amount, the total aboveground biomass (cauliflower (1120.19 g plant^–1)  and lettuce (389,16 g plant^–1))was higher than in the MC cauliflower (1127.07 g plant^–1) and MC lettuce (440.14 g plant^–1). Nitrogen × cropping system interaction was not significant for plant weight. Similarly, the highest leaf weight, head diameter, head height and head weight were generally obtained from 240 N kg ha^–1 in MC and/or IC treatments (Table 2 and 3). 240 N kg ha^–1 in sole and/or intercropping treatment gave the highest leaf number in 1^st year whereas there was no significant difference between treatments. There was no significant difference between treatments in regard to stem diameter in 2^nd year. 200 and 240 N kg ha^–1 treatment increased the stem diameter compared to the other treatments in in 1^st year.

It was observed that different nitrogen dose applications in both IC and MC statistically affected the leaf chlorophyll reading value in cauliflower in both years (Table 2). While the chlorophyll value was the highest in 240 kg N ha^–1 dose application with both IC (66.25 in 1^st year, and 67.65 in 2^nd year) and MC (62.30 in 1^st year, and in 70.05 2^nd year) cauliflower. Difference between chlorophyll reading values was not significant (p>0.05) in 200 and 240 N kg ha^–1 treatment in MC for both experiment years (Table 2). Two years average chlorophyll value of the cauliflower for MC and IC treatment were 66.17 and 66.95 when 240 kg ha^–1 nitrogen was applied, respectively. Although plant chlorophyll increased by 1.17% in IC system compared to MC for cauliflower. First year, the highest dry matter ratio (%) of head was in the MC cauliflower (12.21%-6.72%) and IC (11.38% -6.20%), when the 240 kg N ha^-1 was applied. Dry matter decreased by 7.08% in IC system compared to MC. But, there was no statisticlaysignificant difference (p>0.05) between all treatments in regard to dry matter ratio (Table 3). It was determined that cauliflower vitamin C content differs in terms of cropping system and applied nitrogen doses, and these differences are statistically significant. It was determined that the highest vitamin C value in cauliflower was reached as 109.5 mg 100 g^–1 and 111.00 mg 100 g^–1 with 200 kg N ha^–1 in MC and as 98,75 mg 100 g^–1 and 90,25 mg 100 g^–1 in cauliflower + leaf lettuce IC in both years, respectively (Table 3). Dry matter decreased by 14.18% in IC system compared to MC.

The results of the study indicated that head weight of cauliflower was significantly affected by nitrogen treatments. In the research, it was observed that the highest head weight of cauliflower was obtained from 240 kg N ha^–1 application dose in sole-cropping of cauliflower in 1^st year. The highest head weight (544.35 g plant^–1) was determined in 240 kg N ha^–1 application in sole-cropping followed by 240 kg N ha^–1 application dose in intercropping (525.43 g plant^–1) in 1^st year while the highest head weight was determined in 240 kg N ha^–1 application in both sole (566.25 g plant^–1) and intercropping (566.75 g plant^–1) systems in 2^nd year. Nitrogen × cropping system interaction of head weight was not significant for both years.

 

It was determined that different nitrogen dose applications on yield of cauliflower statistically affected yield of cauliflower in both intercropping and sole cropping in both years (Figure 3). In the research, it was observed that the highest yield was 18.1 ton ha^–1 in the 240 kg N ha^–1 application of sole cauliflower in 1^st year while the least yield amount was determined in cauliflower + leaf lettuce at 160 kg N ha^–1 application (13.7 ton ha^–1). In 2^nd year, the highest yield was observed in the application of cauliflower + leaf lettuce with 240 kg N ha^–1 (18.9 ton ha^–1) whereas the lowest yield was determined in the application of cauliflower + leaf lettuce with 160 kg N ha^–1 (16.9 ton ha^–1) (Figure 3).

Two years average plant yield value of the cauliflower for MC and IC treatment were 18.5 ton ha^–1 (18,1 and 18.9 ton ha^–1 ) and 18.2 ton ha^–1 (17,5 and 18.9 ton ha^–1 )when 234,7 kg ha^-1  and 176,6 kg ha^-1  nitrogen was applied, respectively. Although plant weight decreased by 1.62% in IC system compared to MC for cauliflower, when IC system was used for the same total area and fertilizer amount, the total aboveground biomass (cauliflower (18.5 ton ha^–1)  and lettuce (73.4 ton ha^–1)) was higher than in the MC cauliflower (18.2 ton ha^–1) and MC lettuce (35.7 ton ha^–1). These result show that fertilizer. The result of this research shows that the IC model is both an economical, ecological and sustainable model, as it allows harvesting 240 kg/ha of fertilizer used only in cauliflower planting and about 35.7 tons/ha of lettuce plant from the same area at the same time. Nitrogen applications significantly affected the plant weight of leaf lettuce in intercropping systems for both years. The highest plant weight of the lettuce was obtained from the sole leaf lettuce cropping (542.65 g plant^–1 in 1^st year and 337.63 in 2^nd year). 240 kg N ha^–1 gave the lowest plant weight of leaf lettuce in intercropping with cauliflower for both years. Cropping methods did not significantly affect plant weight, leaf dry matter ratio, and stem diameter. Nitrogen × cropping system interaction was not significant for these parameters (Table 4).

 

 

3. Some conclusion was made, but not based on the study results. For example, “minimizing environmental risks”, “intercropping systems should be included for higher yield and income”. environmental risks and income were not evaluate in the manuscript.

Two years average plant yield value of the cauliflower for MC and IC treatment were 18.5 ton ha^–1 (18,1 and 18.9 ton ha^–1 ) and 18.2 ton ha^–1 (17,5 and 18.9 ton ha^–1 )when 234,7 kg ha^-1  and 176,6 kg ha^-1  nitrogen was applied, respectively. Although plant weight decreased by 1.62% in IC system compared to MC for cauliflower, when IC system was used for the same total area and fertilizer amount, the total aboveground biomass (cauliflower (18.5 ton ha^–1)  and lettuce (73.4 ton ha^–1)) was higher than in the MC cauliflower (18.2 ton ha^–1) and MC lettuce (35.7 ton ha^–1). These result show that fertilizer. The result of this research shows that the IC model is both an economical, ecological and sustainable model, as it allows harvesting 240 kg/ha of fertilizer used only in cauliflower planting and about 35.7 tons/ha of lettuce plant from the same area at the same time

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.Lack of soil physicochemical properties and elements analysis at different soil depths under Intercropping of cauliflower and lettuce.

 

Unfortunately, we couldn’t measure soil physicochemical properties and elements analysis at different soil depths

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear Authors,
The performed correction is insufficient. I believe that the manuscript should be thoroughly revised.

Author Response

RESPONSE TO REVIEWERS First of all, I would like to extend our gratitude to the anonymous reviewers for forwarding very constructive criticism of the MS and giving us an opportunity to improve the standard of the MS. We are glad to state that all suggestions forwarded by the reviewer have been incorporated in their entirety and none has been left unaddressed.

Reviewer 2

Dear Authors,
The performed correction is insufficient. I believe that the manuscript should be thoroughly revised.

Agreeing to reviewer’s suggestion, we have made the corrections

 

Different nitrogen dose applications and cropping methods on soil macro and micronutrient were statistically (p<0.001) significant in both years (Table 8). According to two years average values, organic matter, N, P, K, Ca, Mg, Zn, Fe, Mn, Cu and B of cauliflower growing soil was the highest in IC growing medium with nitrogen 240 kg N ha^–1, 200 P₂O₅ ha^–1 and 120 kg K₂O ha^–1. The findings of the study showed that IC used for the same total area and fertilizer amount, the total aboveground biomass) was more efficient method to increase soil quality index as organic matter, N, P, K, Ca, Mg, Zn, Fe, Mn, Cu and B.  However, MC decreased the organic matter, N, P, K, Ca, Mg, Zn, Fe, Mn, Cu and B of content of cauliflower growing soil.

 

Author Response File: Author Response.pdf

Reviewer 3 Report

This manuscript determines the effect of different nitrogen doses in cauliflower+leaf lettuce intercropping on plant growth, yield, plant nutrient element content, and Land Equivalent Ratio in Turkey. This study is helpful in improving the understanding of nitrogen response in cauliflower+leaf lettuce intercropping. It is a well-written manuscript and has substantial merit. Despite my support, I have a few concerns before considering it for publication. 

This study reported that the yield of cauliflower was significantly affected by different nitrogen level applications, and cauliflower intercropping with leaf lettuce can be more effective than sole cauliflower cropping to utilize and increase the total yield obtained per unit area. However, the optimal level of fertilizer depends on several parameters. Determination of optimal nitrogen level is a function of several factors; residual soil nitrate-nitrogen, and choice of the crop response function.

Past studies have shown that crops get nitrogen from applied and carryover nitrogen from the previous year. The accumulation of carryover N significantly affects crop yield. Without accounting for carryover, residual nitrogen in crop production may not be efficient, and recommended nitrogen levels may be sub-optimal (under or over). Authors should acknowledge this limitation or recommendation for future studies. See the following article, for instance. 

• Maaz, T., & Pan, W. (2017). Residual fertilizer, crop sequence, and water availability impact rotational nitrogen balances. Agronomy Journal, 109(6), 2839-2862.

Another neglected issue is fitting the appropriate crop yield response function as a fitting simple linear function, or ANOVA might not result in the optimal nitrogen doses. I understand the scope of this manuscript is not about finding the best functional forms, but I would like to see mentioning this factor somewhere in the text. Please see the following manuscript that talks about both of these issues in optimal fertilizer decision rules. 

• Dhakal, C., & Lange, K. (2021). Crop yield response functions in nutrient application: A review. Agronomy Journal, 113(6), 5222-5234.

Be precise on the amount of nitrogen you recommend based on this study.

Please cite and provide references following the journal's format.

Author Response

RESPONSE TO REVIEWERS First of all, I would like to extend our gratitude to the anonymous reviewers for forwarding very constructive criticism of the MS and giving us an opportunity to improve the standard of the MS. We are glad to state that all suggestions forwarded by the reviewer have been incorporated in their entirety and none has been left unaddressed.

 

Reviewer 3

This manuscript determines the effect of different nitrogen doses in cauliflower+leaf lettuce intercropping on plant growth, yield, plant nutrient element content, and Land Equivalent Ratio in Turkey. This study is helpful in improving the understanding of nitrogen response in cauliflower+leaf lettuce intercropping. It is a well-written manuscript and has substantial merit. Despite my support, I have a few concerns before considering it for publication. 

This study reported that the yield of cauliflower was significantly affected by different nitrogen level applications, and cauliflower intercropping with leaf lettuce can be more effective than sole cauliflower cropping to utilize and increase the total yield obtained per unit area. However, the optimal level of fertilizer depends on several parameters. Determination of optimal nitrogen level is a function of several factors; residual soil nitrate-nitrogen, and choice of the crop response function.

 

Two years average plant yield value of the cauliflower for MC and IC treatment were 18.5 ton ha^–1 (18,1 and 18.9 ton ha^–1 ) and 18.2 ton ha^–1 (17,5 and 18.9 ton ha^–1 )when 234,7 kg ha^-1  and 176,6 kg ha^-1  nitrogen were applied, respectively (Figure 6). Although plant weight decreased by 1.62% in IC system compared to MC for cauliflower, when IC system was used for the same total area and fertilizer amount, the total aboveground biomass (cauliflower (18.5 ton ha^–1)  and lettuce (73.4 ton ha^–1)) was higher than in the MC cauliflower (18.2 ton ha^–1) and MC lettuce (35.7 ton ha^–1). These result show that fertilizer. The result of this research shows that the IC model is both an economical, ecological and sustainable model, as it allows harvesting 176,6 kg/ha of fertilizer used only in cauliflower planting and about 35.7 tons/ha of lettuce plant from the same area at the same time. Nitrogen applications significantly affected the plant weight of leaf lettuce in intercropping systems for both years. The highest plant weight of the lettuce was obtained from the sole leaf lettuce cropping (542.65 g plant^–1 in 1^st year and 337.63 in 2^nd year). 240 kg N ha^–1 gave the lowest plant weight of leaf lettuce in intercropping with cauliflower for both years. Cropping methods did not significantly affect plant weight, leaf dry matter ratio, and stem diameter. Nitrogen × cropping system interaction was not significant for these parameters (Table 4)

 

 

 

 

 

 

 

 

 

 

Past studies have shown that crops get nitrogen from applied and carryover nitrogen from the previous year. The accumulation of carryover N significantly affects crop yield. Without accounting for carryover, residual nitrogen in crop production may not be efficient, and recommended nitrogen levels may be sub-optimal (under or over). Authors should acknowledge this limitation or recommendation for future studies. See the following article, for instance. 

• Maaz, T., & Pan, W. (2017). Residual fertilizer, crop sequence, and water availability impact rotational nitrogen balances. Agronomy Journal, 109(6), 2839-2862.

Another neglected issue is fitting the appropriate crop yield response function as a fitting simple linear function, or ANOVA might not result in the optimal nitrogen doses. I understand the scope of this manuscript is not about finding the best functional forms, but I would like to see mentioning this factor somewhere in the text. Please see the following manuscript that talks about both of these issues in optimal fertilizer decision rules. 

• Dhakal, C., & Lange, K. (2021). Crop yield response functions in nutrient application: A review. Agronomy Journal, 113(6), 5222-5234.

Be precise on the amount of nitrogen you recommend based on this study.

Please cite and provide references following the journal's format.

Growth characteristics of cauliflower were significantly affected by nitrogen fertilization treatments whereas the effect of cropping treatments usually was nonsignificant (p>0.05) in yield and yield parameters (Table 2 and 3). A statistically significant (p<0.001) difference between plant weights in treatments was determined for both years. In both years, the highest plant weight was achieved as 1086.65 g plant^–1 (1^st year) and 1167.50 g plant^-1 (2^nd year) in the monocropping (MC) treatment when 240 kg ha^–1 nitrogen was applied. Intercropping did not significantly affect the plant weight, and 1082.55 g plant^–1 (1^st year) and 1157.83 g plant^–1 (2^nd year) plant weight was obtained in the intercropping (IC) treatment when 240 kg ha^–1 nitrogen was applied. Two years average plant weight value of the cauliflower for MC and IC treatment were 1127,01 g plant^–1 and 11120.19 g plant^–1 when 240 kg ha^–1 nitrogen was applied, respectively. Although plant weight decreased by 0.61% in IC system compared to MC for cauliflower, when IC system was used for the same total area and fertilizer amount, the total aboveground biomass (cauliflower (1120.19 g plant^–1) and lettuce (389,16 g plant^–1)) was higher than in the MC cauliflower (1127.07 g plant^–1) and MC lettuce (440.14 g plant^–1). Nitrogen × cropping system interaction was not significant for plant weight. Similarly, the highest leaf weight, head diameter, head height and head weight were generally obtained from 234 ,7 N kg ha^–1 in MC and/or IC treatments (Table 2 and 3) according to regression analysis (Figure 6.). 240 N kg ha^–1 in sole and/or intercropping treatment gave the highest leaf number in 1^st year whereas there was no significant difference between treatments. There was no significant difference between treatments in regard to stem diameter in 2^nd year. 200 and 240 N kg ha^–1 treatment increased the stem diameter compared to the other treatments in in 1^st year.

It was observed that different nitrogen dose applications in both IC and MC statistically affected the leaf chlorophyll reading value in cauliflower in both years (Table 2). While the chlorophyll value was the highest in 240 kg N ha^–1 dose application with both IC (66.25 in 1^st year, and 67.65 in 2^nd year) and MC (62.30 in 1^st year, and in 70.05 2^nd year) cauliflower. Difference between chlorophyll reading values was not significant (p>0.05) in 200 and 240 N kg ha^–1 treatment in MC for both experiment years (Table 2). Two years average chlorophyll value of the cauliflower for MC and IC treatment were 66.17 and 66.95 when 240 kg ha^–1 nitrogen was applied, respectively. Although plant chlorophyll increased by 1.17% in IC system compared to MC for cauliflower. First year, the highest dry matter ratio (%) of head was in the MC cauliflower (12.21%-6.72%) and IC (11.38% -6.20%), when the 240 kg N ha^-1 was applied. Dry matter decreased by 7.08% in IC system compared to MC. But, there was no statisticlaysignificant difference (p>0.05) between all treatments in regard to dry matter ratio (Table 3). It was determined that cauliflower vitamin C content differs in terms of cropping system and applied nitrogen doses, and these differences are statistically significant. It was determined that the highest vitamin C value in cauliflower was reached as 109.5 mg 100 g^–1 and 111.00 mg 100 g^–1 with 200 kg N ha^–1 in MC and as 98,75 mg 100 g^–1 and 90,25 mg 100 g^–1 in cauliflower + leaf lettuce IC in both years, respectively (Table 3). Two years average vitamin C value of the cauliflower for MC and IC treatment were 110,25 mg 100 g^-1 and 94.5 mg 100 g^-1 when 234,7 kg ha^-1 and 176,6 kg ha^-1  nitrogen were applied, respectively. Although plant weight decreased by 14,2% in IC system compared to MC for cauliflower.

The results of the study indicated that head weight of cauliflower was significantly affected by nitrogen treatments. In the research, it was observed that the highest head weight of cauliflower was obtained from 240 kg N ha^–1 application dose in sole-cropping of cauliflower in 1^st year. The highest head weight (544.35 g plant^–1) was determined in 240 kg N ha^–1 application in sole-cropping followed by 240 kg N ha^–1 application dose in intercropping (525.43 g plant^–1) in 1^st year while the highest head weight was determined in 240 kg N ha^–1 application in both sole (566.25 g plant^–1) and intercropping (566.75 g plant^–1) systems in 2^nd year. Two years average head weight value of the cauliflower for MC and IC treatment were 555.3 g plant^–1 and 546.09 g plant^–1 when 234,7 kg ha^-1 and 176,6 kg ha^-1  nitrogen were applied, respectively. Although plant weight decreased by 1.65% in IC system compared to MC for cauliflower. Nitrogen × cropping system interaction of head weight was not significant for both years.

It was determined that different nitrogen dose applications on yield of cauliflower statistically affected yield of cauliflower in both IC and MC in both years (Figure 3). In the research, it was observed that the highest yield was 18.1 ton ha^–1 in the 240 kg N ha^–1 application of sole cauliflower in 1^st year while the least yield amount was determined in cauliflower + leaf lettuce at 160 kg N ha^–1 application (13.7 ton ha^–1). In 2^nd year, the highest yield was observed in the application of cauliflower + leaf lettuce with 240 kg N ha^–1 (18.9 ton ha^–1) whereas the lowest yield was determined in the application of cauliflower + leaf lettuce with 160 kg N ha^–1 (16.9 ton ha^–1) (Figure 3). Two years average plant yield value of the cauliflower for MC and IC treatment were 18.5 ton ha^–1 (18,1 and 18.9 ton ha^–1 ) and 18.2 ton ha^–1 (17,5 and 18.9 ton ha^–1 ) when 234,7 kg ha^-1  and 176,6 kg ha^-1 nitrogen were applied, respectively according to regression analysis (Figure 6).  Although plant weight decreased by 1.62% in IC system compared to MC for cauliflower, when IC system was used for the same total area and fertilizer amount, the total aboveground biomass (cauliflower (18.5 ton ha^–1) and lettuce (73.4 ton ha^–1)) was higher than in the MC cauliflower (18.2 ton ha^–1) and MC lettuce (35.7 ton ha^–1). The result of this research shows that the IC model is both an economical, ecological and sustainable model, as it allows harvesting 176,6 kg/ha of fertilizer used only in cauliflower planting and about 35.7 tons/ha of lettuce plant from the same area at the same time. Nitrogen applications significantly affected the plant weight of leaf lettuce in intercropping systems for both years. The highest plant weight of the lettuce was obtained from the MC leaf lettuce cropping (542.65 g plant^–1 in 1^st year and 337.63 in 2^nd year) and gave the lowest plant weight of leaf lettuce in IC with cauliflower for both years. Cropping methods did not significantly affect plant weight, leaf dry matter ratio, and stem diameter. Nitrogen × cropping system interaction was not significant for these parameters (Table 4).

The leaf dry matter ratio of leaf lettuce was significantly (p<0.001) affected by nitrogen fertilization in both years. The highest leaf dry matter ratio was determined in MC and 160 and 240 kg N ha^–1 of IC systems in 1^st year while was in MC and 200 kg N ha^–1 of IC systems in 2^st year. The highest amount of vitamin C in leaf lettuce in 1^st year and 2^nd year were determined in cauliflower + leaf lettuce 160 kg N ha^–1 as 74.33 mg 100g^–1 and 79.75 mg 100g^–1, respectively. Vitamin C content decreased with increased nitrogen doses in IC systems. Nitrogen × cropping system interaction was not significant (Table 4). While the chlorophyll reading value of leaf lettuce was the highest at 200 kg N ha^–1 (53.23) for cauliflower + leaf lettuce in 1^st year, it was found in the application of 240 kg N ha^–1 (55.55) for cauliflower + leaf lettuce in 2^nd year. The least amount of chlorophyll reading value of leaf lettuce was in cauliflower + leaf lettuce with 160 kg N ha^–1 (49.05) in 1^st year, and in sole leaf lettuce with 160 kg N ha^–1 (46.50) application in 2^nd year (Table 4).

Different nitrogen dose applications and cropping methods on leaf lettuce yield were statistically (p<0.001) significant in both years (Figure 4). Yield of leaf lettuce was the highest in MC leaf lettuce growing in both years (90.5 ton ha^–1 and 56.3 ton ha^–1). MC leaf lettuce growing yield was higher than intercropping growth system due to the number of plants per unit area. Nitrogen × cropping system interaction was not significant for yield (Figure 4).

The findings of the study showed that nitrogen fertilization treatments and cropping systems significantly (p<0.001) affected N, NO₃, P, K and Ca content of the cauliflower. NO₃, N, P, K, Ca, Mg, Mn and B content of cauliflower leaves elevated with increasing N doses in both sole and intercropping systems. However, intercropping decreased the content of NO₃, N, Ca, Mg and Mn content of cauliflower leaves. P, K, Fe, Cu and B content of cauliflower leaves changed based on years. The highest NO₃, N and Ca were detected in 234,7 kg N ha^–1 of MC (Table 5, 6 and 7).

Different nitrogen dose applications and cropping methods on soil macro and micronutrient were statistically (p<0.001) significant in both years (Table 8). According to two years average values, organic matter, N, P, K, Ca, Mg, Zn, Fe, Mn, Cu and B of cauliflower growing soil was the highest in IC growing medium with nitrogen 176,6 kg N ha^–1, 200 P₂O₅ ha^–1 and 120 kg K₂O ha^–1. The findings of the study showed that IC used for the same total area and fertilizer amount, the total aboveground biomass) was more efficient method to increase soil quality index as organic matter, N, P, K, Ca, Mg, Zn, Fe, Mn, Cu and B.  However, MC decreased the organic matter, N, P, K, Ca, Mg, Zn, Fe, Mn, Cu and B of content of cauliflower growing soil.

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

no coment

Author Response

Q1. The novelty aspects and its underlying concepts are not clear in this manuscript.

R1. We added the “ The aim of this study is to increase agricultural profitability and sustainability by in-creasing the crop production obtained from the unit area by using the same field and the same inputs.” part to the article as the purpose of the article

Q2.The results and discussion in the manuscript is too descriptive and much of them only literature was provided to support these mechanisms but no data.

R2.In the result section, the data presented in the tables and figures are explained one by one, the yield and yield parameters obtained in the case of growing cauliflower alone and in the case of growing it together with lettuce were compared and presented as percentage differences in addition to the increase and decrease figures. In the discussion part, it was tried to compare the obtained results with the studies on this subject.

Q3. Some conclusion was made, but not based on the study results. For example, “minimizing environmental risks”, “intercropping systems should be included for higher yield and income”. environmental risks and income were not evaluate in the manuscript.

R3. We have written the explanations you want in the discussion section.

As seen in the results of the research, only 18.5 tons of cauliflower product is obtained from the area where cauliflower is grown MC, while a total of 50.7 tons of product is obtained for 32.5 tons of lettuce plant in addition to the cauliflower product with the same fertilizer application in IC. When you take into account the nitrogen fertilizer used per hectare, 18.2 tons of product is obtained with 240 kg of nitrogenous fertilizer, while an additional 35.2 tons of product is taken with the same fertilizer without any change in cauliflower yield, the use of nitrogen fertilizer causes about 2.71 times more effective use. Especially considering that nitrogen fertilizer is washed away from the soil, co-sowing and washing loss are reduced, as well as effective use of nitrogen ferti-lizer, resulting in a reduction in production costs. Considering the two-year soil results, the increase in soil organic matter causes an increase in the bacterial activity of the soil, and this positive effect causes an increase in the usefulness of the nutrients. As seen in the results, we can see that the biodiversity increases and the availability of nutrients (P, K, Mgi Zn, Fe, Mn, Cu) increases as it is directly proportional to the increase in the number of plants per unit area and the total amount of C.

Q4.Lack of soil physicochemical properties and elements analysis at different soil depths under Intercropping of cauliflower and lettuce.

R4. Information on soil properties was given in table 8 in the article.

Q5. This manuscript determines the effect of different nitrogen doses in cauliflower+leaf lettuce intercropping on plant growth, yield, plant nutrient element content, and Land Equivalent Ratio in Turkey. This study is helpful in improving the understanding of nitrogen response in cauliflower+leaf lettuce intercropping. It is a well-written manuscript and has substantial merit. Despite my support, I have a few concerns before considering it for publication. This study reported that the yield of cauliflower was significantly affected by different nitrogen level applications, and cauliflower intercropping with leaf lettuce can be more effective than sole cauliflower cropping to utilize and increase the total yield obtained per unit area. However, the optimal level of fertilizer depends on several parameters. Determination of optimal nitrogen level is a function of several factors; residual soil nitrate-nitrogen, and choice of the crop response function.Past studies have shown that crops get nitrogen from applied and carryover nitrogen from the previous year. The accumulation of carryover N significantly affects crop yield. Without accounting for carryover, residual nitrogen in crop production may not be efficient, and recommended nitrogen levels may be sub-optimal (under or over). Authors should acknowledge this limitation or recommendation for future studies. See the following article, for instance. 

• Maaz, T., & Pan, W. (2017). Residual fertilizer, crop sequence, and water availability impact rotational nitrogen balances. Agronomy Journal, 109(6), 2839-2862.

Another neglected issue is fitting the appropriate crop yield response function as a fitting simple linear function, or ANOVA might not result in the optimal nitrogen doses. I understand the scope of this manuscript is not about finding the best functional forms, but I would like to see mentioning this factor somewhere in the text. Please see the following manuscript that talks about both of these issues in optimal fertilizer decision rules. 

• Dhakal, C., & Lange, K. (2021). Crop yield response functions in nutrient application: A review. Agronomy Journal, 113(6), 5222-5234.

Be precise on the amount of nitrogen you recommend based on this study.

Please cite and provide references following the journal's format.

R5. In our study, no study was conducted by targeting residual fertilizer effectiveness. It is aimed to increase the yield by growing lettuce as an intermediate sowing with the same fertilizer application amount without loss in yield when the most effective dose of different nitrogen fertilizer doses is mixed planting. The most effective dose determination on yield and yield parameters of nitrogen fertilizers applied at different doses was evaluated by quadric relationship.

Reviewer 2 Report

Dear Authors,

The manuscript is significantly improved.

Please consider the following comments:

1) Statistical analysis - what was the normality test of the data distribution performed?

2)       - // -                - whether (and with what test) the homogeneity of variance in the samples was tested, it is a necessary condition for the use of ANOVA.

3) Figure 3. Effects of N fertilizer… correct superscript in figure (^-1)

4) Figure 4. Optimum N… R² - just round to hundredths (0.94)

5) Figure 5 and 6 see point. 3 above

Author Response

Q1. The novelty aspects and its underlying concepts are not clear in this manuscript.

R1. We added the “ The aim of this study is to increase agricultural profitability and sustainability by in-creasing the crop production obtained from the unit area by using the same field and the same inputs.” part to the article as the purpose of the article

Q2.The results and discussion in the manuscript is too descriptive and much of them only literature was provided to support these mechanisms but no data.

R2.In the result section, the data presented in the tables and figures are explained one by one, the yield and yield parameters obtained in the case of growing cauliflower alone and in the case of growing it together with lettuce were compared and presented as percentage differences in addition to the increase and decrease figures. In the discussion part, it was tried to compare the obtained results with the studies on this subject.

Q3. Some conclusion was made, but not based on the study results. For example, “minimizing environmental risks”, “intercropping systems should be included for higher yield and income”. environmental risks and income were not evaluate in the manuscript.

R3. We have written the explanations you want in the discussion section.

As seen in the results of the research, only 18.5 tons of cauliflower product is obtained from the area where cauliflower is grown MC, while a total of 50.7 tons of product is obtained for 32.5 tons of lettuce plant in addition to the cauliflower product with the same fertilizer application in IC. When you take into account the nitrogen fertilizer used per hectare, 18.2 tons of product is obtained with 240 kg of nitrogenous fertilizer, while an additional 35.2 tons of product is taken with the same fertilizer without any change in cauliflower yield, the use of nitrogen fertilizer causes about 2.71 times more effective use. Especially considering that nitrogen fertilizer is washed away from the soil, co-sowing and washing loss are reduced, as well as effective use of nitrogen ferti-lizer, resulting in a reduction in production costs. Considering the two-year soil results, the increase in soil organic matter causes an increase in the bacterial activity of the soil, and this positive effect causes an increase in the usefulness of the nutrients. As seen in the results, we can see that the biodiversity increases and the availability of nutrients (P, K, Mgi Zn, Fe, Mn, Cu) increases as it is directly proportional to the increase in the number of plants per unit area and the total amount of C.

Q4.Lack of soil physicochemical properties and elements analysis at different soil depths under Intercropping of cauliflower and lettuce.

R4. Information on soil properties was given in table 8 in the article.

Q5. This manuscript determines the effect of different nitrogen doses in cauliflower+leaf lettuce intercropping on plant growth, yield, plant nutrient element content, and Land Equivalent Ratio in Turkey. This study is helpful in improving the understanding of nitrogen response in cauliflower+leaf lettuce intercropping. It is a well-written manuscript and has substantial merit. Despite my support, I have a few concerns before considering it for publication. This study reported that the yield of cauliflower was significantly affected by different nitrogen level applications, and cauliflower intercropping with leaf lettuce can be more effective than sole cauliflower cropping to utilize and increase the total yield obtained per unit area. However, the optimal level of fertilizer depends on several parameters. Determination of optimal nitrogen level is a function of several factors; residual soil nitrate-nitrogen, and choice of the crop response function.Past studies have shown that crops get nitrogen from applied and carryover nitrogen from the previous year. The accumulation of carryover N significantly affects crop yield. Without accounting for carryover, residual nitrogen in crop production may not be efficient, and recommended nitrogen levels may be sub-optimal (under or over). Authors should acknowledge this limitation or recommendation for future studies. See the following article, for instance. 

• Maaz, T., & Pan, W. (2017). Residual fertilizer, crop sequence, and water availability impact rotational nitrogen balances. Agronomy Journal, 109(6), 2839-2862.

Another neglected issue is fitting the appropriate crop yield response function as a fitting simple linear function, or ANOVA might not result in the optimal nitrogen doses. I understand the scope of this manuscript is not about finding the best functional forms, but I would like to see mentioning this factor somewhere in the text. Please see the following manuscript that talks about both of these issues in optimal fertilizer decision rules. 

• Dhakal, C., & Lange, K. (2021). Crop yield response functions in nutrient application: A review. Agronomy Journal, 113(6), 5222-5234.

Be precise on the amount of nitrogen you recommend based on this study.

Please cite and provide references following the journal's format.

R5. In our study, no study was conducted by targeting residual fertilizer effectiveness. It is aimed to increase the yield by growing lettuce as an intermediate sowing with the same fertilizer application amount without loss in yield when the most effective dose of different nitrogen fertilizer doses is mixed planting. The most effective dose determination on yield and yield parameters of nitrogen fertilizers applied at different doses was evaluated by quadric relationship.

Reviewer 3 Report

It appears that the authors did not understand my comments correctly. 

Please have re-posted my remarks. 

Past studies have shown that crops get nitrogen from applied and carryover nitrogen from the previous year. The accumulation of carryover N significantly affects crop yield. Without accounting for carryover, residual nitrogen in crop production may not be efficient, and recommended nitrogen levels may be sub-optimal (under or over). Authors should acknowledge this limitation or recommendation for future studies. See the following article, for instance. 

• Maaz, T., & Pan, W. (2017). Residual fertilizer, crop sequence, and water availability impact rotational nitrogen balances. Agronomy Journal, 109(6), 2839-2862.

Another neglected issue is fitting the appropriate crop yield response function as a fitting simple linear function, or ANOVA might not result in the optimal nitrogen doses. I understand the scope of this manuscript is not about finding the best functional forms, but I would like to see mentioning this factor somewhere in the text. Please see the following manuscript that talks about both of these issues in optimal fertilizer decision rules. 

• Dhakal, C., & Lange, K. (2021). Crop yield response functions in nutrient application: A review. Agronomy Journal, 113(6), 5222-5234.

Be precise on the amount of nitrogen you recommend based on this study.

Please cite and provide references following the journal's format.

Author Response

Q1. The novelty aspects and its underlying concepts are not clear in this manuscript.

R1. We added the “ The aim of this study is to increase agricultural profitability and sustainability by in-creasing the crop production obtained from the unit area by using the same field and the same inputs.” part to the article as the purpose of the article

Q2.The results and discussion in the manuscript is too descriptive and much of them only literature was provided to support these mechanisms but no data.

R2.In the result section, the data presented in the tables and figures are explained one by one, the yield and yield parameters obtained in the case of growing cauliflower alone and in the case of growing it together with lettuce were compared and presented as percentage differences in addition to the increase and decrease figures. In the discussion part, it was tried to compare the obtained results with the studies on this subject.

Q3. Some conclusion was made, but not based on the study results. For example, “minimizing environmental risks”, “intercropping systems should be included for higher yield and income”. environmental risks and income were not evaluate in the manuscript.

R3. We have written the explanations you want in the discussion section.

As seen in the results of the research, only 18.5 tons of cauliflower product is obtained from the area where cauliflower is grown MC, while a total of 50.7 tons of product is obtained for 32.5 tons of lettuce plant in addition to the cauliflower product with the same fertilizer application in IC. When you take into account the nitrogen fertilizer used per hectare, 18.2 tons of product is obtained with 240 kg of nitrogenous fertilizer, while an additional 35.2 tons of product is taken with the same fertilizer without any change in cauliflower yield, the use of nitrogen fertilizer causes about 2.71 times more effective use. Especially considering that nitrogen fertilizer is washed away from the soil, co-sowing and washing loss are reduced, as well as effective use of nitrogen ferti-lizer, resulting in a reduction in production costs. Considering the two-year soil results, the increase in soil organic matter causes an increase in the bacterial activity of the soil, and this positive effect causes an increase in the usefulness of the nutrients. As seen in the results, we can see that the biodiversity increases and the availability of nutrients (P, K, Mgi Zn, Fe, Mn, Cu) increases as it is directly proportional to the increase in the number of plants per unit area and the total amount of C.

Q4.Lack of soil physicochemical properties and elements analysis at different soil depths under Intercropping of cauliflower and lettuce.

R4. Information on soil properties was given in table 8 in the article.

Q5. This manuscript determines the effect of different nitrogen doses in cauliflower+leaf lettuce intercropping on plant growth, yield, plant nutrient element content, and Land Equivalent Ratio in Turkey. This study is helpful in improving the understanding of nitrogen response in cauliflower+leaf lettuce intercropping. It is a well-written manuscript and has substantial merit. Despite my support, I have a few concerns before considering it for publication. This study reported that the yield of cauliflower was significantly affected by different nitrogen level applications, and cauliflower intercropping with leaf lettuce can be more effective than sole cauliflower cropping to utilize and increase the total yield obtained per unit area. However, the optimal level of fertilizer depends on several parameters. Determination of optimal nitrogen level is a function of several factors; residual soil nitrate-nitrogen, and choice of the crop response function.Past studies have shown that crops get nitrogen from applied and carryover nitrogen from the previous year. The accumulation of carryover N significantly affects crop yield. Without accounting for carryover, residual nitrogen in crop production may not be efficient, and recommended nitrogen levels may be sub-optimal (under or over). Authors should acknowledge this limitation or recommendation for future studies. See the following article, for instance. 

• Maaz, T., & Pan, W. (2017). Residual fertilizer, crop sequence, and water availability impact rotational nitrogen balances. Agronomy Journal, 109(6), 2839-2862.

Another neglected issue is fitting the appropriate crop yield response function as a fitting simple linear function, or ANOVA might not result in the optimal nitrogen doses. I understand the scope of this manuscript is not about finding the best functional forms, but I would like to see mentioning this factor somewhere in the text. Please see the following manuscript that talks about both of these issues in optimal fertilizer decision rules. 

• Dhakal, C., & Lange, K. (2021). Crop yield response functions in nutrient application: A review. Agronomy Journal, 113(6), 5222-5234.

Be precise on the amount of nitrogen you recommend based on this study.

Please cite and provide references following the journal's format.

R5. In our study, no study was conducted by targeting residual fertilizer effectiveness. It is aimed to increase the yield by growing lettuce as an intermediate sowing with the same fertilizer application amount without loss in yield when the most effective dose of different nitrogen fertilizer doses is mixed planting. The most effective dose determination on yield and yield parameters of nitrogen fertilizers applied at different doses was evaluated by quadric relationship.

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

1.We did not see the research significance and methods in the abstract.

2.The preface was too verbose, and the introduction of intercropping and familiar nouns was excessive, showing no progress in previous research.

3.Some details in the article should be carefully examined, such as none of the units in the figure were set the superscript, whether lines 248 and 251 should be changed to p> 0.05, the 082.55 g plant^–1 data has an error for line 184.

4.There was too little part of the conclusions about this study, mainly in writing the significance of the study, and the research significance should be placed in the preface part.

5.We did not see any valuable discussion, Discussion needs to be more in-depth.

Reviewer 2 Report

The work is good, but the results of the experiment seem to be very limited, since the importance of these production systems in Turkey in terms of planted area and economic contribution is not clearly established.

 

If the objective of the work is analyzed, the information that is included in the results chapter is extensive, due to the variables that are included and described but that do not contribute to the fulfillment of the main objective of the work, so it becomes very long and in confusing occasions to read the article, losing the sense of the most important thing.

 

The most important aspect is related to the experimental design used, there is doubt about the way in which the data was analyzed and, consequently, the results are not presented and discussed in the appropriate way; for example, in some variables the extreme values ​​are mentioned, without considering whether there are other treatments that are statistically equal. The interaction effects between fertilization and the sowing system are not mentioned either, despite the fact that the document mentions that two factors were handled and that, therefore, the interaction effects must be considered. This is repeated when the years are compared, since this comparison is only using the values ​​presented by the variables and not a statistical comparison. Perhaps a model that considers in a more appropriate way the interaction analysis could contribute to give a greater support to the investigation.

In the text of the article some observations are marked that should be addressed to try to give greater clarity to the publication.

Comments for author File: Comments.pdf

Reviewer 3 Report

Dear Authors,
Agrotechnical / agronomic experiments are extremely labor-intensive. Each agricultural research requires appropriate preparation and planning. Unfortunately, the work in its current form is not ready for publication.
The basic drawback of the experiment is only the 2-year research period - which is a methodological error. The analysis of the results, in my opinion, is not reliable. Detailed comments below.
1) The authors planned a field agricultural experiment lasting 2 years. Agricultural experiments, in uncontrolled (field) conditions, should be carried out in 3-4 repetitions in order to eliminate the influence of variable factors (mainly weather conditions).
2) The assumptions of the statistical analysis of the results do not indicate that the year of the study was treated as an independent variable (see line 170) - and yet in the results of the study (Figures 3 and 4, and the tables of results), the years of the study (2014 and 2015) are treated as if they differed statistically significant.
3) It was indicated that the studied population of data meets the conditions for a normal distribution - however, it is not known by what method this condition was determined. The homogeneity of variance has not been tested - and according to statistics it is a necessary condition for the application of parametric tests (such as ANOVA).
4) No baseline ANOVA results; F-Snedecor test value, MS, SS, number of degrees of freedom ...).