Screening Candidate Genes at the Co Locus Conferring to the Columnar Growth Habit in Apple (Malus × Domestica Borkh.)

Round 1

Reviewer 1 Report

The present study has the objective to make a strategy of screening and to select 11 candidate genes by experimental cloning, transient expression, and genetic transformation.

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.

Reviewer 2 Report

Dear Editor,

 Many thanks for letting me review the paper titled "Screening Candidate Genes at the Co Locus Conferring to Columnar Growth Habit in Apple (Malus×Domestica Borkh.)" by Guo et al. In the mentioned paper, the authors screened 11 selected candidate genes using transient expression and gene transformation. They also found 4 SNPs, and the location of the genes in different organelles of the plants. They also found the function of some genes including MdCo38-OE, NTPIN1, and NtGA2ox in tobacco (a model plant). They also found the Co genotyping of some genes including MdCo38 and MdCC041, which are involved in the columnar growth phenotype in apple, probably through altering polar auxin transport, active gibberellin levels, and strigolactone biosynthesis. 

After careful consideration of the paper, I believe that the paper is suitable for publication in the current format. The statical analysis of the paper is suitable, and the results are clear. The introduction and tittle of the paper show the trend of the experiment currently and the results and discussion are strong.

The paper meets the standards to be published in the journal.