Morphological, Sensorial and Chemical Characterization of Chilli Peppers (Capsicum spp.) from the CATIE Genebank

Round 1

Reviewer 1 Report

Introduction

• Considering the aims of the paper (i.e. line 87), the reproductive system of the analysed species (outcrossing rate) is useful. Also, the number of chromosomes of the species is informative.

Mthodology

Morohological characterization

• Coordinates, altitude and rainfall information are not important for the location where the germplasm bank is located (ex situ). It is significant  if the experimental field has been established in that place (specify).
• How was the experiment carried out? (experimental design?)
• How many plants per accession were used for trait detection?
• I think it is better if the descriptors are presented in a table by adding the type of expression and the methods for measuring the character (unit of measurement)

Partecipatory selection

On how many accessions has it been made?
Are they the same as the morphological characterization? To specify

Chemical characterization
How many samples per accession were analyzed?

Results

• I do not understand which data were used for the constitution of the dendrogram of figure 1.
• In line 266 the authors speak about combined analysis of quantitative and qualitative variables while in the caption of figure 1 only the quantitative variables are reported 
• The biplot (Figure 2) needs to be discussed in more detail

Discussion and Conclusions 

• Line 419 - The authors say: " while the quantitative characteristics that present the highest discriminant value were fruit weight, fruit width and fruit length.....where does this come from?
• The discussion needs to be improved

Other revisions

Line 67- specify here the acronym CATIE (as it appears for the first time)

Line 78- After these are add : 

Line 204, Line 205 and Line 207 -  The authors refer to the Groups (G3, G7 etc.) of the dendrogram without referring to Figure 1

Line 275 - The number of accessions of the dendrogram cannot be read well

Line 287 - The first three values ​​of the coefficient (P) have the letter "a" why?

Author Response

Dear Madam/Sir,

Please find our responses to your comments in the attached document.

Sincerely,

Marten Sørensen

Author Response File: Author Response.docx

Reviewer 2 Report

Paper needs to be much better organised, separating description of traits into methods, and comments on other findings into the discussion.

Need to rigorously explain categories of "promising', 'excellent', 'very good' and presumably 'rejected' which is not reported.

Need to explain why different numbers of accessions were chosen for evaluation by growers/processors, and by consumers. The result is that reporting of results is non-orthogonal and non-systematic. This can lead to the impression of selectivity and guiding results to a preconceived conclusion, instead of an objective analysis of genetic diversity.

This paper needs to be better structured, with clearer aims, whether of fruit quality/nutrition, or identification of key discriminatory factors whether agro-ecological adaptation variation, or morphological growth differentiation, or of harvest yield components. If a combination of these, then subsets could be identified, e.g. within fruit categories for species and respective adaptations and morphologies. 

Anther colour and flower colour are important botanical descriptors, but are these relevant to fruit characteristics? 

The information is buried in the paper, but needs to be better presented.

Author Response

Dear Madam/Sir,

Please find our responses to your comments in the attached document.

Sincerely,

Marten Sørensen

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The paper has been improved, and the proposed suggestions have been made

Author Response

Revised version of the manuscript (submission no. agronomy-952836)

Author Response File: Author Response.docx

Reviewer 2 Report

This paper sets out to describe germplasm characterisation, but also provides a plant breeding method for selecting the best accessions for fruit quality and nutrition. As such the aims of the paper are confused,

An appendix could list accessions in the ‘Good’, ‘Regular’, ‘Poor’, categories to provide more complete information about variation in the collection.

The membership of groups had a minority of other accessions in addition to the major accession in Groups 1. 2, 3, 4, 6, 7, and 9. The clustering mainly reflected species, but not fully. This needs more explanation in the discussion.

The description of the most discriminate traits does not match the eigen values in axes 1 and 2.

For Table 6 the contents do not match the description in the text, and ‘blade’ is used in the table, but presumably is ‘leaf’ in the text.

Table 7 should include chemical analyses of all 15 accession chosen, and has incomplete columns for traits analysed.

A clearer description is needed for 134 accessions rated very good, with a subset of 34 selected on fruit colour, shape and size, from which a sub-subset of 15 was chosen for chemical analyses. This is expedient for selection of the best quality accessions, however this procedure is specific to the collection in the CATIE genebank at that time. It could be different for another genebank collection with a different choice of growers and consumers and hence cannot be a standard evaluation for sharing among genebanks.

The authors should consider changing the title to reflect the content of the paper.

Author Response

COVER LETTER

REVIEWER 2

This paper sets out to describe germplasm characterisation, but also provides a plant breeding method for selecting the best accessions for fruit quality and nutrition. As such the aims of the paper are confused,

Objetives were edited for greater clarity, the following subtitles were also ordered so there is agreement with the objectives.

“The objectives of this study were: a) to determine the level of morphological diversity present in 192 accessions of Capsicum; b) to identify the qualitative and quantitative characters with high discriminating capacity; c) to classify Capsicum species into groups based on their quantitative and qualitative  characteristics; d)  to identify germplasm through participatory sensory evaluation; and e)  to determine the chemical characteristics of promising materials”

Additionally, the title was also modified to clarify the extent of the study.

“Morphological, sensorial and chemical characterization of chilli peppers (Capsicum spp.) from the CATIE genebank”

An appendix could list accessions in the ‘Good’, ‘Regular’, ‘Poor’, categories to provide more complete information about variation in the collection.

An appendix was inserted at the end related to the evaluation of 34 selected accessions; scale has been clarified in the text (methodology) and in the appendix.

The membership of groups had a minority of other accessions in addition to the major accession in Groups 1. 2, 3, 4, 6, 7, and 9. The clustering mainly reflected species, but not fully. This needs more explanation in the discussion.

Explanation about the standing above has been clarified

Line 448 to 458 as follow>

“The agronomic characterization allowed classifying the genetic variability of the Capsicum germplasm collection into two large groups and nine subgroups. The two large groups are formed by the subgroups G7, G8, G5 and G3 represented by C. annuum, and the second group formed by subgroups G4, G9, G6, G2 having mostly C. frutescens accessions plus G1 represented mainly by C. baccatum. Subgroup 1 (G1) differentiates from the other subgroups because of the presence of spots on the corolla (Corollar spot colour) similarly as observed by García [48]; Palacios & García [66] and Walsh & Hoot [67].  It is important to notice that within all subgroups (except G8) there are few intercalated accessions of C. baccatum, C. pubescens, C. chinense and C. spp. (Table 4).  Capsicum phylogeny determined closer relation among C. annuum, C. frutescens and C. chinense which is known as C. annuum complex Pickersgill, [43], Vallejo et al. [49], Pardey et al. [18] and Palacios and García [66]. “

The description of the most discriminate traits does not match the eigen values in axes 1 and 2.

For Table 6 the contents do not match the description in the text, and ‘blade’ is used in the

For clarification descriptors listed in Table 6 has been modified according to the original published descriptors, and the list was re-ordered according to eigen values axis 1 from bigger to lower. 

On lines 301 to 305 the following text was inserted:

“Regarding the quantitative descriptors, six were identified with the highest discriminant value: leaf length/width ratio, width mature leaf, fruit length, fruit width, fruit wall thickness, plant height; these descriptors allowed to differentiate the nine groups (Table 6). In addition, we determined that accessions within the groups maintain a close relationship, once there is not much variation since they present small values ​​of standard deviation. “

Additionally:

• Table 7 was also modified changing ug to mg to standardize units.
• Section discussion and conclusions was completely reorganized and edited, including some new references.

• References were edited according to AGRONOMY standards.

• Some error with decimal punctuation was modified by using ( . ) as decimal separator.
• From line 132 to 147, methodology for Participatory sensory evaluation was revised and edited.

Author Response File: Author Response.pdf