Development of KASP and SSR Markers for PmQ, a Recessive Gene Conferring Powdery Mildew Resistance in Wheat Landrace Qingxinmai
, Dan Qiu 1,3, Qiuhong Wu 3, Hongjun Zhang 1, Li Yang 1, Yang Zhou 1, Yijun Zhou 2, Zhiyong Liu 3, Peng Zhang 4,* and Hongjie Li 1,*
Round 1
Reviewer 1 Report
PmQ is a recently exploited gene from a wheat landrace that confers effective resistance to wheat powdery mildew, showing a great value for breeding. In the manuscript, Gebremedhin et al developed more molecular markers to further map the gene and assessed the potential of the new markers for MAS. On the whole, the MS is well written and the conclusion is supported by the data. I suggest some minor revisions before acceptance.
L22: the meaning of “motif” is not clear.
L108: the authors should provide the website.
L213-L234: Since Pm52 and PmJM22 are close to PmQ, if the markers developed here may trace them and may be used for MAS of them? If it is possible, the authors may discuss it.
Table S1 and S2: I suggest the authors remove the two supplementary tables to the main text, in which, non-polymorphic markers could be deleted.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Breeder-friendly molecular markers are necessary for introgressing the target gene into adapted wheat backgrounds for developing disease resistant wheat cultivars. A gene PmQ conferring powdery mildew resistance was previously localized on chromosome 2BL in winter wheat landrace Qingxinmai. This study developed three KASP and two SSR markers based on the results of BSR-Seq analysis and the motifs in the reference genome sequences of the target genomic region, respectively. The results provided a powerful foundation for MAS of PmQ in wheat breeding. In general, it is an interesting and valuable story which merit publication. I recommend accepting it for publication after revision listed as below.
1. Recessive gene can be lower-case. Just like pmQ.
2. Line 20: Please specify the full name of “BSR-Seq”.
3. Line 31: “Triticum aestivum L.” should be “Triticum aestivum L.”
4. Line 34-35: Please check the sentence “The obligate biotropic fungus Blumeria graminis f. sp. tritici (Bgt) causing wheat powdery mildew disease is almost everywhere wheat is grown”.
5. Line 63: Pm should be Pm, please check the whole manuscript carefully to avoid the mistakes of formats.
6. Line 69: please add “such as”.
7. Line 83: “were” should be “was”.
8. If possible, please provide the detailed information of 160 modern wheat cultivars or advanced breeding lines.
9. Line 149: “confirms” should be “confirmed”.
10. Line 164: “makers” should be “markers”.
Overall, I could fully understand this manuscript. However, I feel that an English editing might be helpful to improve its readability. In addition, please check the format of the whole manuscript carefully.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
31: Scientific names and gene names should be in italics (please check throughout the draft).
71: Is Qingxinmai conserved somewhere in the public domain? If so, please specify the institute/location where the germplasm is stored. Is the PI accession number available? If it is not publicly available germplasm, recommend you explain why.
76: Why did you choose two types of marker technology; SNP/KASP and SSR? Especially why you need to develop SSR markers which are a bit outdated marker technology in general. Was there no SNP or small INDEL found in the genomic area of interest?
82: Please share the list of 160 modern wheat cultivars in the supplementary table. And please explain the criteria to select the 160 lines.
91: The symptom was phenotyped twice. Please specify the interval of those two times.
107: Need some explanation of what SSR motifs were your target for designing SSR markers such as dinucleotide repeats, trinucleotide repeats, etc.
147 to 150: I appreciate the authors demonstrated it which is very important for genetics research. However, researchers frequently forgot to test heritability before running linkage mapping using markers. One additional fact is needed. PmQ is a recessive gene. Please demonstrate the way you confirmed it’s a recessive gene such as phenotype screening etc. If there are previous studies available, please address them.
164: Practically, KASP is not a new type of molecular marker technology which has been introduced in early 2000 and actively adopted in wheat breeding since then.
172: Could you share which SNP allele is resistant or susceptible to the 3 KASP markers?
174 to 180 (Figure 3): In addition to the cM information, please add the physical location information of the markers and PmQ for readers’ convivence. Simply recycle the information you already captured in the supplementary table.
215 to 218: Could you address what are the favorable (resistant) allele and unfavorable (susceptible) allele of those 4 markers such as SNP and # of repeats?
In general, I don't see significant scientific novelty. However, the data that the authors presented are very useful for wheat breeding programs. And the results and discussions were demonstrated pretty clearly.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
