Mycosphaerella Brassicicola Resistant Brassica Oleracea Plants

Abstract

Provided herein are Mycosphaerella brassicicola resistant Brassica oleracea plants including a resistance providing genomic fragment including SEQ ID Nos. 1 and 3. The present Mycosphaerella brassicicola resistant Brassica oleracea plants do not include a resistance providing genomic fragment comprising SEQ ID Nos. 2 and 4. Also provided herein are methods for identifying the present plants and the use of the disclosed sequences for identifying Mycosphaerella brassicicola resistant Brassica oleracea plants.

Claims

1. A Mycosphaerella brassicicola resistant Brassica oleracea plant, wherein the plant comprises a resistance providing genomic fragment comprising SEQ ID Nos. 1 and 3.

2. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment does not comprise SEQ ID Nos. 2 and 4.

3. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment further comprises one or more sequences selected from the group consisting of SEQ ID No. 5, SEQ ID No. 7, SEQ ID No. 9, SEQ ID No. 11, SEQ ID No. 13, SEQ ID No. 15, and SEQ ID No. 17 and SEQ ID No. 23.

4. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment not comprises one or more sequences selected from the group consisting of SEQ ID No. 6, SEQ ID No. 8, SEQ ID No. 10, SEQ ID No. 12, SEQ ID No. 14, SEQ ID No. 16, and SEQ ID No. 18 and SEQ ID No. 24.

5. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment is flanked on the left side by SEQ ID No. 19 and/or SEQ ID No. 21 and on the right side by SEQ ID No. 25.

6. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment is flanked on the left side by SEQ ID No. 20 and/or SEQ ID No. 22 and on the right side by SEQ ID No. 26.

7. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment comprises SEQ ID No. 1, SEQ ID No. 3, SEQ ID No. 5, SEQ ID No. 7, SEQ ID No. 9, SEQ ID No. 11, SEQ ID No. 13, SEQ ID No. 15, SEQ ID No. 17, SEQ ID No. 19, SEQ ID No. 21, SEQ ID No. 23 and SEQ ID No. 25.

8. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment does not comprise SEQ ID No. 2, SEQ ID No. 4, SEQ ID No. 6, SEQ ID No. 8, SEQ ID No. 10, SEQ ID No. 12, SEQ ID No. 14, SEQ ID No. 16, SEQ ID No. 18, SEQ ID No. 20, SEQ ID No. 22, SEQ ID No. 24 and SEQ ID No. 26.

9. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the resistance providing genomic fragment is obtainable, obtained or derived from a Brassica plant of which representative seed are deposited under NCIMB 43445.

10. The Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, wherein the plant is a hybrid plant.

11. A method for identifying a Mycosphaerella brassicicola resistant Brassica oleracea plant according to claim 1, the method comprises the step of establishing the presence a resistance providing genomic fragment comprising one or more nucleic acid sequences selected from the group consisting of SEQ ID No. 1, SEQ ID No. 3, SEQ ID No. 5, SEQ ID No. 7, SEQ ID No. 9, SEQ ID No. 11, SEQ ID No. 13, SEQ ID No. 15, SEQ ID No. 17, SEQ ID No. 19, SEQ ID No. 21, SEQ ID No. 23 and SEQ ID No. 25 in the genome of the Mycosphaerella brassicicola resistant Brassica oleracea plant.

12. (canceled)

13. A method for providing a Mycosphaerella brassicicola resistant Brassica oleracea plant, wherein the method comprises the step of introgressing a resistance providing genomic fragment as defined in claim 1 into a Brassica oleracea plant.

14. The method according to claim 13, wherein the Brassica oleracea plant is a Mycosphaerella brassicicola susceptible Brassica oleracea plant.

15. A nucleic acid sequence selected from the group consisting of SEQ ID No. 1 to SEQ ID No. 26.

Description

DETAILED DESCRIPTION

[0036] The present invention will be further detailed in the following example.

Example

[0037] Determining Resistance to M. brassicicola

[0038] Disease tests were performed in a field where M. brassicicola infection occurs by the ascospores present. No artificial infection is performed described. After 10 to 14 days the symptoms of M. brassicicola infection are assessed and scored on a scale from 0 (plant is dead) to 9 (plant has no symptoms).

Molecular Characterization of Genomic DNA and Mapping of the Resistance Gene

[0039] Several backcross populations were produced by crossing and repeated backcrossing of the source of resistance, deposited as NCIMB 43445 and a variety of B. oleracea cultivars.

[0040] A set of SNP markers were developed by comparing sequence data from lines susceptible and resistant to M. brassicicola. These SNP markers were repeatedly mapped on different Brassica populations and by selecting cross-overs. With these cross-over generations, the mapped region was narrowed down. The reference genome was the broccoli (B. oleracea convar. botrytis var. cymosa) HDEM assembly as described.

[0041] The analysis of several generations of plants made it possible to reduce the genetic location of the resistance gene to an area of ˜50,000 bp which corresponds to approx. 0.3% of this chromosome. Sequences analysis of the area identified yielded the present uneven SEQ ID Nos. 1 to 25. Similarly, sequence analysis of the corresponding area in susceptible plants yielded the present even SEQ ID Nos. 2 to 26. Accordingly, a large number of genomic sequences could be identified enabling a precise and rapid identification of plants harboring the gene resulting in resistance to M. brassicicola. Individual plants were selected by breeders from the several backcross programmes where the disease resistance was combined with the highest level of agronomical quality.