Effects of Biostimulants on Primary and Secondary Substance Contents in Lettuce Plants
Round 1
Reviewer 1 Report
Effects of Bio-stimulants on Primary and Secondary Substance Contents in Lettuce Plants submitted to Sustainability journal.
I found paper quite interesting. The subject of natural biostimulants is widely investigated, however, the idea of use plant wastes to extract some bioactive substances and reuse them is always worth attention.
The use of extracts as spray for lettuce leaves didn’t change much the composition of samples in respect to lettuce flavonoid, mineral and amino acids content. However, still all research was conducted reliably. What I missed was photos whole plant and weight of leaves. Also my advice is to use biostimulants as soil fertilizer in future research.
Author Response
Reviewer 1
Effects of Bio-stimulants on Primary and Secondary Substance Contents in Lettuce Plants submitted to Sustainability journal.
I found paper quite interesting. The subject of natural biostimulants is widely investigated, however, the idea of use plant wastes to extract some bioactive substances and reuse them is always worth attention.
The use of extracts as spray for lettuce leaves didn’t change much the composition of samples in respect to lettuce flavonoid, mineral and amino acids content.
Response: Yes, although the extracts did not change the composition of samples much in respect to lettuce flavonoid, mineral and amino acids content, the biostimulants used in this study worth did not have a negative effect. You might find our previous study of interest as well (reference 15 in this MS; Horticultural Science and Technology 37(3): 322-336, 2019; Italian Journal of Agronomy 14:1488, 2019).
However, still all research was conducted reliably. What I missed was photos whole plant and weight of leaves. Also my advice is to use biostimulants as soil fertilizer in future research.
Response: Thanks for this suggestion. In future studies we will include more photos. With regards to application method, we are currently carrying out studies with biostimulants applied using various application methods (including soil application).
Reviewer 2 Report
General comments
The article entitled ‘Effects of Bio-stimulants on Primary and Secondary Substance Contents in Lettuce Plants’ fits well the scope of Sustainability. The manuscript is written in proper English without typos and syntax mistakes and contains sufficient literature. The study highlights the effects of the use of 3 bio-stimulants in lettuce cultivation. Bio-stimulants derived from soybean leaves and stems and Chinese chives by-products. Water extracts from the above-mentioned plants were applied by foliar spays in lettuce plants grown under the same conditions and cultivation practices. Authors conducted determinations of total phenolics and flavonoids, DPPH antioxidant activity, minerals, amino acids and sugars. Finally, they proposed that the nutritional value of lettuce was improved by the use of the plant extract foliar application examined in their experiments. Therefore, my recommendation is to accept the manuscript after minor revision.
Line 84: authors are advised to explain briefly how the water extracts used were obtained.
Lines 93 – 97: this paragraph can be moved to the above section.
Line 106: ‘AlCl3’ instead of ‘AlCl3’.
Line 109: replace ‘supernatant’ with ‘extract’.
Lines 98, 124: authors are advised to mention the conditions under plant tissues were dried. Are the same with those in the section to the mineral analyses?
Line 142: authors can give more details about HPLC analysis, such as flow rate, column specifications, column temperature, solvent used, etc., since there is no reference.
Line 152, 153: replace ‘activities’ with ‘activity’.
Line 156: add (Table 1) at the end of the sentence.
Line 171: authors are advised to use either ‘days after treatments’ or ‘hours, the use of both is confusing.
Lines 214, 215, 218: ammonia is not an amino acid, authors can either remove it from the results and tables or explain why they included.
Line 242: since sucrose and maltose were not detected, authors can delete them from results and Table 9. For the same reason they can delete sucrose from Table 10.
Comments for author File: 
Comments.pdf
Author Response
Reviewer 2
The article entitled ‘Effects of Bio-stimulants on Primary and Secondary Substance Contents in Lettuce Plants’ fits well the scope of Sustainability. The manuscript is written in proper English without typos and syntax mistakes and contains sufficient literature. The study highlights the effects of the use of 3 bio-stimulants in lettuce cultivation. Bio-stimulants derived from soybean leaves and stems and Chinese chives by-products. Water extracts from the above-mentioned plants were applied by foliar spays in lettuce plants grown under the same conditions and cultivation practices. Authors conducted determinations of total phenolics and flavonoids, DPPH antioxidant activity, minerals, amino acids and sugars. Finally, they proposed that the nutritional value of lettuce was improved by the use of the plant extract foliar application examined in their experiments. Therefore, my recommendation is to accept the manuscript after minor revision.
Line 84: authors are advised to explain briefly how the water extracts used were obtained.
Response: Please see materials section of MS. Corrections have been made.
Lines 93 – 97: this paragraph can be moved to the above section.
Response: Corrected
Line 106: ‘AlCl3’ instead of ‘AlCl3’.
Response: Corrected
Line 109: replace ‘supernatant’ with ‘extract’.
Response: Corrected
Lines 98, 124: authors are advised to mention the conditions under plant tissues were dried. Are the same with those in the section to the mineral analyses?
Response: Yes, conditions for drying plant tissue were the same as those mentioned in the mineral analyses.
Line 142: authors can give more details about HPLC analysis, such as flow rate, column specifications, column temperature, solvent used, etc., since there is no reference.
Response: We cited a reference (Wilson et al. 1981) regarding the HPLC analysis which addresses flow rate, etc.
Line 152, 153: replace ‘activities’ with ‘activity’.
Response: Corrected
Line 156: add (Table 1) at the end of the sentence.
Response: Corrected
Line 171: authors are advised to use either ‘days after treatments’ or ‘hours, the use of both is confusing.
Response: Corrected
Lines 214, 215, 218: ammonia is not an amino acid, authors can either remove it from the results and tables or explain why they included.
Response: In order to reduce any confusion, we have removed amonia data from the manuscript.
Line 242: since sucrose and maltose were not detected, authors can delete them from results and Table 9. For the same reason they can delete sucrose from Table 10.
Response: Corrected
Reviewer 3 Report
The research presented in the manuscript 'Effects of Bio-stimulants on Primary and Secondary Substance Contents in Lettuce Plants' addresses a needed topic in current knowledge the sustainable intensification of agriculture. About this topic plant bio-stimulants could be elected as a new paradigm for the sustainable intensification of crops.
GENERAL COMMENTS AND ADVICES:
The manuscript could be improved, exceptionally in introduction and methods. In this last could be added number of seeds, leaves or the number of replication use for the anova analysis.
I also suggest joining tables: i.e. 3 and 4,
Tables 9 and 10 could be move in supplementary material adding these information in the text, considering also that some value were equal to zero
Tables as 5 and 6, 7 and 8 could be transformed as histogram chart with standard deviation and / or significant different at 5% level.
Line 60: change with 7-8 time per years
Line 116, 124, 131, 138 in the text it’s better to write gram and not ‘g’ , also for the sentences started with a number , translate it in letters.
Minor revision is recommended.
Author Response
Reviewer 3
The research presented in the manuscript 'Effects of Bio-stimulants on Primary and Secondary Substance Contents in Lettuce Plants' addresses a needed topic in current knowledge the sustainable intensification of agriculture. About this topic plant bio-stimulants could be elected as a new paradigm for the sustainable intensification of crops.
GENERAL COMMENTS AND ADVICES:
The manuscript could be improved, exceptionally in introduction and methods. In this last could be added number of seeds, leaves or the number of replication use for the anova analysis.
Response: We added the replication number to the methods section.
I also suggest joining tables: i.e. 3 and 4,
Response: Respectfully, we think that joining those two tables could make interpreting the data more difficult and could possibly cause some confusion. As such, we will keep the tables separate.
Tables 9 and 10 could be move in supplementary material adding these information in the text, considering also that some value were equal to zero
Response: Reviewer 2 commented that since sucrose and maltose were not detected, authors can delete them from results and Table 9. For the same reason they can delete sucrose from Table 10. Thus, we corrected them in MS as reviewer 2 comments.
Tables as 5 and 6, 7 and 8 could be transformed as histogram chart with standard deviation and / or significant different at 5% level.
Response: To make histogram charts, tables 5, 6, 7, and 8 is too complex and also very difficult for comparison between treatments.
Line 60: change with 7-8 time per years
Response: Corrected.
Line 116, 124, 131, 138 in the text it’s better to write gram and not ‘g’ , also for the sentences started with a number , translate it in letters.
Response: Corrected.
