Narrative
CU17NBL is an acylsugar benchmark breeding line, which was developed to replace the former benchmark line, CU071026. CU071026 had reproductive limitations, setting fruit in the Ithaca NY area only when sown in November or December in the greenhouse. When sown from May to about October and grown in greenhouse or field (in summer) CU071026 flowers but either does not set any fruit or sets very few fruit with little seed. Seed of CU071026 also have lower germination percentages than standard tomato. CU17NBL produces the same type of acylsugar, at the same level, as CU071026, however CU17NBL sets fruit and seed normally year-round, and its seed has normal germination.
The creation of the major Cornell acylsugar lines including CU071026 and CU17NBL is reviewed in the publication by Mutschler (2021).
CU17NBL has 5 S. pennellii introgressions which combined are ca. 11% of the CU17NBL genome. The locations and sizes of these locations using the 2.5 genome build are:
• Chromosome 2: the Chr2 introgression, from 53,792,960 - 55,238,304 bp: Therefore, it is 1,445,344 bp in length.
• Chromosome 3: the Chr3 introgression, from 2,143,744 - 64,451,474 bp: Therefore, it is 62,307,730 bp length.
• Chromosome 7: the Chr7 introgression, from 65,554,074 – 65,801,666 bp: Therefore, it is 247,592 bp in length.
• Chromosome 8: the Chr8 introgression, from 60,843,834 – 63,384,503 bp: Therefore, it is 1,445,344 bp in length
• Chromosome 10: the Chr10U introgression, from 0 - 1,916,909 bp: Therefore, it is 2,540,669 bp in length.
CU17NBL is the background into which a series of lines has been created and deposited into the USDA germplasm collection. This series of lines was created by transferring 1 to 3 additional S. pennellii introgressions into CU17NBL from a line of the set of lines previously created in the CU071026 set of acylsugar lines. The names of the lines created in the CU17NBL background, in addition to CU17NBL/NO 8, and which were also deposited, are
1. QTL6/CU17NBL
2. QTL6/SW-5/CU17NBL
3. Sw-5/CU17NBL
4. FA2/CU17NBL
5. FA7/CU17NBL
6. FA2/FA7/CU17NBL
7. FA5/CU17NBL
8. Acylglucose/CU17NBL, also known as AGLU3/AGLU4/AGLU11/CU17NBL
9. Acylglucose+chr12/CU17NBL, also known as AGLU3/AGLU4/AGLU11/ACYL12/CU17NBL
Each of these 9 lines in the CU17NBL background are very similar in acylsugar level and acylsugar types to that of their analogous line in the set of lines in the CU071026 background. A publication regarding creation of these lines and their complete characterizations is in preparation.
CU17NBL/NO 8 is another variant of CU17NBL that lacks one introgression, which is on chromosome 8. The acylsugars produced by CU17NBL/NO 8 are similar to those in CU17NBL, although the level of acylsugars in CU17NBL/NO 8 is less than that in CU17NBL