TABLE 1.
Cytological characterization of male-defective mutants of S. latifolia
| Size of deletion (%) | Meiosisa
|
||||
|---|---|---|---|---|---|
| Mutant names | Diakinesis | Metaphase I | X–Y pairing | Other changes | |
| ad1 | 9 | 12 | 12 | Wild type | |
| ad2 | 12 | 12 | 12 | No or interstitial (36%) | |
| ad3 | Not measurable | 12 | 12 | Interstitial (11%) | 10% abnormal segregation in meiosis II |
| ad4 | 13 | 12 | 12 | Wild type | |
| ad5 | Not measurable | 12 | 12 | Wild type | |
| pf1 | 4 | 12 | 12 | Wild type | |
| pf2 | Not measurable | Not studied | Not studied | Wild type | |
| pf3 | Not measurable | 12 | 12 | Wild type | |
| pf4 | Not measurable | 12 and 13 (10%) | Mitotic divisions of one bivalent | Wild type | |
| pf5 | Not measurable | 14 | Wild type | ||
| ad6 (msp1) | 8 | 12 | 12 | Wild type | |
| ad7 (msp2) | 7 | 12 | 12 | Extensive X–Y pairing (84%) | |
| asx1 | 20 | No meiosis | Not testable | ||
| asx2 | 12 | No meiosis | Not testable | ||
The second column of the table shows the sizes of the Y deletions measured in mitotic cell preparations, as a percentage of the entire Y chromosome. An extensive meiotic analysis was performed to estimate bivalent formation during diakinesis and metaphase I (columns 3 and 4), other meiotic aberrations (column 5), and X–Y pairing behavior (column 6).
a
See Lardon et al. (1999): number of bivalents are known to vary from 2n = 12 to 2n = 14 in S. latifolia genotypes, with no consequences for the sex phenotype.