Estimating Heat Requirement for Flowering in Peach Germplasm

Round 1

Reviewer 1 Report

This paper establishes the heat requirements for flowering of 136 peach cultivars in the western USA. These data are very valuable since little information is available when compared to available data on chilling requirements. One of the reasons for this fact is the lack of a robust method to establish when to start counting heat accumulation, as well as the limits of the GDH model, which despite being widely used its accuracy must be questioned. I find this work interesting, but I have two major concerns:

 

• One approach to quantifying HR is to start counting GDH from February 15, an arbitrary date considered for dormancy overcoming. I understand that this is perhaps a common practice for growers and technicians, but our current scientific knowledge indicates that RH is cultivar specific and varies from year to year depending on temperatures. I think this part of the study can be eliminated as it does not add anything new.
• GDH is an important trait to take into account in breeding programs, as it determines the phenology and adaptability of cultivars to different regions. However, the difficulties in characterizing this trait (when the GHD starts to be counted, how is the transition from the cooling to the warming phase, the low accuracy of the GDH model...) is the main limitation to understand the genetic background and inheritance. This limitation has to be considered in the discussion. I also suggest to indicate other approaches for HR characterization such as the method applied by Bielenberg and Gasic 2022. The methodology used to characterize HR is important when comparing with other studies and understanding the performance of the results.

 

The paper is interesting and well-written, but I miss a clearer interpretation and discussion of the results. For the details of the revision please look at the PDF.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The present study has the objective to investigated heat requirement for floral bud break in the U.S. peach germplasm over eight different climatic years

The experiment seems to be carefully planned and carried out with a high degree of care. Materials and methods section and the statistical tests used are appropriated.

From my point of view, the introduction section provides useful information on the background and the state-of-art of the topic of the article.

The results and discussion part are explained in detail.

Finally, the references listed are appropriate.

Author Response

We thank the reviewer for comments and have improved the English language and readability of the manuscript. We hope the reviewer finds the changes acceptable.

Round 2

Reviewer 1 Report

I consider that the paper is now suitable for publication.