Yam Nematodes as Production Constraints in Ghana: A Socio-Economic Perspective
, Daniel Dzidzienyo 5 and Ranjana Bhattacharjee 2,*
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsYam is important for Ghana and its farmers, so this makes this work interesting. Look at the title of this paper! The last part is socio-economic perspective. We can see that the economic status of farmers with the size of their farms varies, and in addition some farmers had no school education, but some even had tertiary education. Some farmers have had long experience in jam cultivation, while some are just starting jam cultivation affecting their status. Anyhow the paper does not show if the economic or social status would affect their ability to control nematodes, to use better storage, more resistance yam strains or more rapid selling the jams so that the storage losses will be reduced. If you can connect the data of economic or social status to the results, please connect! And fulfill part 3.6! If you cannot connect those data, omit the last three words of your title and the part 3.6. Think if you could or should publish this data in some other forum. If you present this on another paper, present the table 6 so that the sites are as columns and the nematode species as rows!
In my country some people or their families own agricultural farms and make agricultural works as a hobby, but the principal income comes from work made for other sectors. Did anyone of the 150 farmers work simultaneously in other sectors, and get a major income from this (despite the fact that they can be good farmers, too)? If connect that to the paper.
You have some errors.
Use in all case hectares or square meters for all areas. I would save with decimals.
Table 1: The northern latitude for Dotobaa is some 7o (not 77o).
Table 3: If the number of farmers with a cultivation period of 1-3 years is 26, how the number of farmers in yam cultivation period of 1-3 years can be 43?
Table 5: present the numbers of “no answer”!
Separate the able to control nematodes and to control nematode infestation.
The soil type may have an effect but if the farm size is only a few hectares, the soil type may be the same in the whole farm and the farmer cannot select this.
Would the heavy rains in tuber formation time effect infestation and the farmer may have some abilities to this problem by selecting a better starting time for yam cultivation and possible a more useful plant rotation or yam and other plant in each second row.
Author Response
Comment 1: Yam is important for Ghana and its farmers, so this makes this work interesting. Look at the title of this paper! The last part is socio-economic perspective. We can see that the economic status of farmers with the size of their farms varies, and in addition some farmers had no school education, but some even had tertiary education. Some farmers have had long experience in jam cultivation, while some are just starting jam cultivation affecting their status. Anyhow the paper does not show if the economic or social status would affect their ability to control nematodes, to use better storage, more resistance yam strains or more rapid selling the jams so that the storage losses will be reduced. If you can connect the data of economic or social status to the results, please connect! And fulfill part 3.6! If you cannot connect those data, omit the last three words of your title and the part 3.6. Think if you could or should publish this data in some other forum. If you present this on another paper, present the table 6 so that the sites are as columns and the nematode species as rows!
Response: We thank the reviewer for bringing this issue to our attention and fully agree with his suggestion. About 92-95% of farmers interviewed managed nematodes on their farms through crop and land rotation. These activities have been carried out over the years, irrespective of their educational status and the size of their farms. However, as per the reviewer's observations, efforts were made to further disaggregate the results by socioeconomic factors to see if there is heterogeneity in the analysis we reported here. Specifically, farm size distribution over time was now included by the sex of the respondents.
Furthermore, we used chi-square test to examine the association between farmers’ storage practices, pest occurrence and major socio-economics variables with nematode management (see Table 6). An exact logistic econometric model to investigate the conditioning factors influencing farmers' choice of postharvest storage practices was also employed. We controlled for covariates such as farmer education level, market orientation, knowledge of Nematode disease, access to extension agents, and farm size when estimating the adoption of postharvest storage practices. We found no correlation between farmers' adoption decisions and the aforementioned controlled variables. As a result, we refrain from reporting this result in the revised manuscript. On the other hand, the limitations of this study not incorporating robust econometrics models to examine the drivers of storage practices and linkage of socioeconomic and social factors due to a smaller sample size and less variability in some outcome variables were included in the revised manuscript.
Comment 2: In my country some people or their families own agricultural farms and make agricultural works as a hobby, but the principal income comes from work made for other sectors. Did anyone of the 150 farmers work simultaneously in other sectors, and get a major income from this (despite the fact that they can be good farmers, too)? If connect that to the paper.
Response: This is a good observation and unfortunately, we did not capture the various income sources in the questionnaire. However, we have a proxy variable that measures the commercialization level of farmers on whether they produce for home consumption or market. This variable was included in the postharvest use model presented in the annex table. Most of the farmers interviewed solely depended on their farming practices for income to be able to take care of their domestic needs.
Comment 3: Use in all case hectares or square meters for all areas. I would save with decimals.
Response: This has been addressed accordingly. All the explanations in the text were converted to hectares. Only the continuous variable presented in the model that was reported in the annex use as acre the unit of measurement.
Comment 4: Table 1: The northern latitude for Dotobaa is some 7o (not 77o).
Response: This has been revised accordingly.
Comment 5: Table 3: If the number of farmers with a cultivation period of 1-3 years is 26, how the number of farmers in yam cultivation period of 1-3 years can be 43?
Response: ‘Cultivating period (years)’ for 1-3 years has been revised to ‘Cultivation of other crops on land (years)’.
Comment 6: Table 5: present the numbers of “no answer”!
Response: We appreciate this observation and it has been addressed in Tables4 & 5.
Comment 7: Separate the able to control nematodes and to control nematode infestation.
Response: This has been revised.
Comment 8: The soil type may have an effect but if the farm size is only a few hectares, the soil type may be the same in the whole farm and the farmer cannot select this.
Response: This is noted and changes made accordingly.
Comment 9: Would the heavy rains in tuber formation time effect infestation and the farmer may have some abilities to this problem by selecting a better starting time for yam cultivation and possible a more useful plant rotation or yam and other plant in each second row.
Response: Rain which increase the moisture content of the soils provide conducive soil environment for nematode population build-up. Therefore, farmers usually plant yams in a particular year and then move to another site the following year. The previous land is then cultivated to another crop for example maize to break the life cycles of the nematodes.
Reviewer 2 Report
Comments and Suggestions for AuthorsSustainability-3293388-peer-review-v1Reviwer 1.
Yam Nematodes as Production Constraint in Ghana: A Socio- Economic Perspectives
The study aimed to investigate production practices and land use intensity by yam farmers, to evaluate farmers’ perception and knowledge of yam nematodes, and characterization of nematode populations present in soils from yams farms and in yam tubers.
The text is well written. Some necessary corrections were highlighted in the pdf file.
Below are some comments on the content of the manuscript.
1. As highlighted throughout the text there is confusion as to the correct use of the terms infestation and infection.
2. Tables 6 and 8: I recommend replacing nematode names on tabletop by abbreviations, then in the table foot notes include the nematode complete name, for example: Sb = Scutellonema bradys. In the same tables, for self-explanatory purpose, indicate the meaning of these table values. For example: number of nematodes per 200 cc soil (table 6) and number of nematodes per 50 g yam peels (table 8).
3. Table 9: Third column, replace POPULATION/200cc SOIL by: POPULATION/50 g yam peel.
4. The manuscript highlights, the root-knot nematodes (Meloidogyne spp.) are also important for yam culture, as well as the results showed that the nematode was frequently found in soil samples and yam tubers, but in the study were not included elements to evaluate the perception of farmers for the recognition of symptoms and losses related to these nematodes in the way it was done for Scutellonema bradys.
5. The classification system adopted was that of Siddiqi (2000), considering the nematodes found in the orders Tylenchida and Dorylaimida. However, at the moment the De Ley & Blaxter (2002) system has greater acceptance, whereby nematodes of the order Tylenchida are considered to belong to the order Rhabditida.
6. The results show that nematodes of the genus Criconemella were found in the soil samples, while nematodes of the genus Mesocriconema were found in the samples of yam tuber peels. Although there is no consensus on the nomenclature of these taxa, it is considered that Criconemella is no longer a valid genus, as defended by Geraert (2011 - Criconematids of the world) who considers Mesocriconema and Criconemoides as valid genera, having as main differential characteristic the presence of open vulva (Mesocriconema) and closed vulva (Criconemoides). Therefore, what is considered in the present study as Criconemella can be Mesocriconema and/or Criconematoides.
7. As highlighted in the manuscript, Bibliographic references require corrections. Some are incomplete and in some of them scientific names have not been italicized.
Comments for author File: 
Comments.pdf
Author Response
Comment 1: As highlighted throughout the text there is confusion as to the correct use of the terms infestation and infection.
Response: We have now corrected throughout the manuscript as suggested and indicated.
Comment 2: Tables 6 and 8: I recommend replacing nematode names on tabletop by abbreviations, then in the table foot notes include the nematode complete name, for example: Sb = Scutellonema bradys. In the same tables, for self-explanatory purpose, indicate the meaning of these table values. For example: number of nematodes per 200 cc soil (table 6) and number of nematodes per 50 g yam peels (table 8).
Response: We appreciate this observation of the reviewer. This Table has been updated and Tables 6 and 8 are now Tables 7 and 9.
Comment 3: Table 9: Third column, replace POPULATION/200cc SOIL by: POPULATION/50 g yam peel.
Response: Table 9 has been updated and is currently Table 10.
Comment 4: The manuscript highlights, the root-knot nematodes (Meloidogyne spp.) are also important for yam culture, as well as the results showed that the nematode was frequently found in soil samples and yam tubers, but in the study were not included elements to evaluate the perception of farmers for the recognition of symptoms and losses related to these nematodes in the way it was done for Scutellonema bradys.
Response: Yes, though Meloidogyne spp. were also identified in the yam peels (4%), their population densities in the yam peels were less compared to the yam nematode. There were other nematode species as well which were identified. Farmers however indicated symptoms which were more prevalent to nematode infection from S. bradys in storage, however, symptoms of M. incognita infestation for example gall formation were minimal in the various locations.
Comment 5: The classification system adopted was that of Siddiqi (2000), considering the nematodes found in the orders Tylenchida and Dorylaimida. However, at the moment the De Ley & Blaxter (2002) system has greater acceptance, whereby nematodes of the order Tylenchida are considered to belong to the order Rhabditida.
Response: ‘Tylenchida’ has been replaced with ‘Rhabditida’
Comment 6: The results show that nematodes of the genus Criconemella were found in the soil samples, while nematodes of the genus Mesocriconema were found in the samples of yam tuber peels. Although there is no consensus on the nomenclature of these taxa, it is considered that Criconemella is no longer a valid genus, as defended by Geraert (2011 - Criconematids of the world) who considers Mesocriconema and Criconemoides as valid genera, having as main differential characteristic the presence of open vulva (Mesocriconema) and closed vulva (Criconemoides). Therefore, what is considered in the present study as Criconemella can be Mesocriconema and/or Criconematoides.
Response: We have revised Criconemella spp. to Mesocriconema spp. in the text and Tables.
Comment 7: As highlighted in the manuscript, Bibliographic references require corrections. Some are incomplete and in some of them scientific names have not been italicized.
Response: References have been updated accordingly.
Reviewer 3 Report
Comments and Suggestions for AuthorsDear Editor
Many thanks for considering me as a potential reviewer for the article "Yam Nematodes as Production Constraint in Ghana: A Socio- Economic Perspectives". The article is undoubtedly well-structured, well-presented and well-written. However, I have several observations that should be considered before proceeding further.
My observations are as follows,
· I am not happy with the English language used. Please check the whole manuscript for grammatical issues, consistency, font size and style i.e. Lines 113-133, some text are under lines why?,
· Please make your abstract shorter and concise,
· Lines 50-54, here you mentioned (According to the Ghana Export Promotion Authority [2], Ghana was the 50 world's top exporter of yams in 2021. The country's yam export value has increased since 2018, from US$ 38.5 million to US$ 48.2 million by 2021. Ghana has a global share of 24.1%, with an annual growth rate of 14% between 2020 and 2021 and an average growth rate of 9% from 2017 to 2021), if Ghana was the top exporter abd increase occurs in the exports as well as in the prices (US$ 38.5 million to US$ 48.2) then how you can claim/certify that Nematodes damages/affect the Yams production?. To have more clarity, please add more statistics sequentially, for example what is the global production? How much Ghana contributing? Decrease occurs (how much) due to Nematodes….
· Line-55 As a staple food… please complete this information by adding more details, its chemical composition etc… due this richer composition of yams it has gain economic importance…..
· If possible, please add the ‘structured questionnaire’ in supplementary file, so that the reader will understand the concept very easily,
· Please improve the graphs quality,
· Tables and Figures in the description are bold, while in the text it is un-bold and short form (Fig.) please follow same patter,
· In the tables you mentioned Freq. but why not Frequency,
· Figure 4 and 5 combine these figures and I will suggest you, please open these figures in power point and organize well and add legends over it, please check Figure 1 DOI: 10.3390/metabo11110769,
· Line-176 50ml should be corrected to 50mL, please ensure this formatting change is applied consistently throughout the manuscript,
· Line-137 please cite ‘Purposive sampling technique’.
Comments on the Quality of English LanguageDear Editor/Authors,
I read the article and I am not happy with the English langauge, several issues were seen, please have an extensive English editing by a Professional and/or senior Professor in the field.
Thanks
Author Response
Comment 1: I am not happy with the English language used. Please check the whole manuscript for grammatical issues, consistency, font size and style i.e. Lines 113-133, some text are under lines why?,
Response: We appreciate the observation of the reviewer and the manuscript has been reviewed again for English language and the appropriated font sizes used.
Comment 2: Please make your abstract shorter and concise,
Response: The abstract has been revised.
Comment 3: Lines 50-54, here you mentioned (According to the Ghana Export Promotion Authority [2], Ghana was the 50 world's top exporter of yams in 2021. The country's yam export value has increased since 2018, from US$ 38.5 million to US$ 48.2 million by 2021. Ghana has a global share of 24.1%, with an annual growth rate of 14% between 2020 and 2021 and an average growth rate of 9% from 2017 to 2021), if Ghana was the top exporter abd increase occurs in the exports as well as in the prices (US$ 38.5 million to US$ 48.2) then how you can claim/certify that Nematodes damages/affect the Yams production?. To have more clarity, please add more statistics sequentially, for example what is the global production? How much Ghana contributing? Decrease occurs (how much) due to Nematodes….
Response: We appreciate the critical observation of the reviewer, we have the statement ‘While cultivation and marketing of yam tubers play a crucial role in the socio-economic conditions of smallholder yam farmers in Ghana, the high prevalence of nematode infestations has significantly hindered the productivity of the farmers and profitability of the enterprise, with farmers attaining yields of only approximately 10 t ha−1 [15], which is merely 20% of the potential yield of 50 t ha−1.’ from lines 90-94 in the manuscript.
Comment 4: Line-55 As a staple food… please complete this information by adding more details, its chemical composition etc… due this richer composition of yams it has gain economic importance…..
Response: The statement has been updated to read ‘As a staple food and a key economic commodity, yams (Dioscorea spp.) support the sustenance and financial stability of millions of smallholder farmers across different yam-producing areas around the world, because this crop contains minerals, micronutrients and essential aminoacids [3-5]’.
A new reference is also added [3]
Wu, Z.G.; Jiang, W.; Nitin, M.; Bao, X.Q.; Chen, S.L.; Tao, Z.M. Characterizing diversity based on nutritional and bioactive compositions of yam germplasm (Dioscorea spp.) commonly cultivated in China. J. Food Drugs Anal. 2016, 24, 367–375.
Comment 5: If possible, please add the ‘structured questionnaire’ in supplementary file, so that the reader will understand the concept very easily,
Response: The questionnaire has been added as a supplementary file.
Comment 6: Please improve the graphs quality
Response: Good observations, most figures and graphs have been revised as per the reviewers comment.
Comment 7: Tables and Figures in the description are bold, while in the text it is un-bold and short form (Fig.) please follow same patter,
Response: This has been revised accordingly.
Comment 8: In the tables you mentioned Freq. but why not Frequency,
Response: ‘Freq’ has been changed to ‘Frequency’.
Comment 9: Figure e 4 and 5 combine these figures and I will suggest you, please open these figures in power point and organize well and add legends over it, please check Figure 1 DOI: 10.3390/metabo11110769,
Response: We have removed these two figures and replaced them with better data visualization.
Comment 10: Line-176 50ml should be corrected to 50mL, please ensure this formatting change is applied consistently throughout the manuscript.
Response: This has been revised.
Comment 11: Line-137 please cite ‘Purposive sampling technique’
Response: We have updated the reference number 16 with, Palinkas, L.A., Horwitz, S.M., Green, C.A., Wisdom, J.P., Duan, N. and Hoagwood, K. Purposeful sampling for qualitative data collection and analysis in mixed method implementation research. Administration and policy in mental health and mental health services research, 2015, 42, pp.533-544.
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsPlease, increase highly the font in Figs 2 and 3. Table 8 what is the population size (column three)? Is it 200 gram?
Author Response
Point-by-point response to Reviewer 1:
Comment 1: Please, increase highly the font in Figs 2 and 3.
Response 1: We appreciate the response of the reviewer. The font size for the two graphs has been adjusted accordingly.
Comment 2: Table 8 what is the population size (column three)? Is it 200 gram?
Response 2: It is 50 gm of yam peels, this is mentioned in the text.
Reviewer 3 Report
Comments and Suggestions for AuthorsDear Editor
Many thanks for the updates, regarding the article status. I don’t know, but I did not find the author’s response file and even didn’t make my recommended changes. Anyhow, below are a few observations that should be addressed,
· Lines 53-56, please cite this information ‘The country's yam export value has increased since 2018, from US$ 38.5 million to US$ 48.2 million by 2021. Ghana has a global share of 24.1%, with an annual growth rate of 14% between 2020 and 2021 and an average growth rate of 9% from 2017 to 2021’.,
· Figure 4, the color of the legend must be off the same color,
· Some information needs to be cited accordingly,
· The article must be checked for spelling, dots and commas etc.
Comments on the Quality of English LanguageDear Authors
Please have a look for the basic issues regarding spelling mistakes.
Thanks
Author Response
Point-by-point response to Reviewer 3:
Comment 1: Many thanks for the updates, regarding the article status. I don’t know, but I did not find the author’s response file and even didn’t make my recommended changes. Anyhow, below are a few observations that should be addressed.
Response 1: We thank the reviewer for his comments and suggestions that helped to improve the quality of the manuscript. The authors had duly submitted ‘point-by-point’ response to All comments of the reviewer in the first round of revision.
Comment 2: Lines 53-56, please cite this information ‘The country's yam export value has increased since 2018, from US$ 38.5 million to US$ 48.2 million by 2021. Ghana has a global share of 24.1%, with an annual growth rate of 14% between 2020 and 2021 and an average growth rate of 9% from 2017 to 2021’.
Response 2: We appreciate the observation of the reviewer, the reference has been provided.
Comment 3: Figure 4, the color of the legend must be off the same color.
Response 3: The Figures 4a and 4b represents pictures of yam storage facilities, we have used the same color.
Comment 4: Some information needs to be cited accordingly,
Response 4: It is not clear which reference the reviewer is referring to, we checked through the manuscript and added references as necessary.
Comment 5: The article must be checked for spelling, dots and commas etc.
Response 5: The manuscript has been checked thoroughly for English language and other issues suggested by the reviewer.
