Presentation on theme: "VC221: Tomato. sequencing 1st criteria: Chromosome with NOR vs without with: chromosome 2 2nd criteria: Position of the centromere a) Median chromosomes."— Presentation transcript:
1st criteria: Chromosome with NOR vs without with: chromosome 2 2nd criteria: Position of the centromere a) Median chromosomes 5, 11, 12 (metacentric) b) Sub median all others (sub-metacentric) 3rd criteria: Short arm heterochromatic regions a) A conspicuous cluster of chromomeres compressed together: chromosomes. 3, 4, 6. b) More than 1 cluster of chromomeres: chromosomes. 1, 7, 10. Key for pachytene chromosome identification
Primary trisomicPachytene and diakinesis/metaphase I: 12II+ 1I, 11II +1III Secondary trisomic Pachytene: Isochromosome paired with itself, triradial III Diakinesis/Met I: 11II +ring of III, 12II + 1I (mini ring). Tertiary trisomicDiakinesis/Met I: 10II + 1V Telo trisomicDiakinesis/Met I: heteromorphic III, or tiny univalent Primary MonosomicDiakinesis/Met I: 11II + 1I Tertiary MonosomicDiakinesis/Met I: 10II + 1III, 10II + 3I
S. lycopersicon typ: S. cheesmaniae min: S. galapagence S. pimpinellifolium S. neorickii S. chemieleskii S. habrochaites S. pennellii S. peruvianum S. arcanum S. Corneliomuellerii S. huayalasense S. chilense Eulycopersicon (color-fruited) Eriopersicon Green-fruited S. lycopersicoides, S. ochrantum, S. sitiens (based on 6 DNA seq, Adh 2, fw2.2)
Esc-pennelli introgression lines Each stock is homozygous for a single chromosome segment (delineated by RFLP markers) introgressed from L. pennellii, such that the entire wild species genome is represented in a group of 50 lines.
Dissection of QTL se2.1(stigma exertion Four loci influencing stamen length (three closely linked) were identified. A single locus for style length was identified (the long style allele was shown to be dominant using esc-penn sustitution lines). A single locus for anther dehiscence was also found in the region. Chen and Tanksley 2004
Fine mapping loci contributing to the se2.1 QTL
Five closely linked genes all contribute to stigma exsertion phenotype. This may be the remnant of a “co adapted gene complex” where linked genes cooperatively contribute to an adaptation, and are inherited as a single unit.
Successful crossUnsuccessful cross S e S e (female) x S 1 S 2 (male) S 1 S 2 (female) x S e S e (male) S e S e (female) x S P S P (male) S P S P (female) x S e S e (male) S P S P (female) x S 1 S 2 (male) S 1 S 2 (female) x S P S P (male) Tomato SI