Table 1. Reduced transmission of the PIRL6-KD constructs.
| Plant Line | Germinated | Glufosinate R:Sa (Ratio) | Expected R:Sb (Ratio) | χ2 (P)c | Interpretation |
|---|---|---|---|---|---|
| T-40s-T2 | 409 | 239:170 (1.4:1) | 307:102 (3:1) | 59.85 (<0.0001) | One insert, reduced transmission |
| T-48L-T2 | 250 | 163:87 (1.9:1) | 188:62 (3:1) | 12.8 (0.0003) | One insert, reduced transmission |
| T-53L-T2 | 235 | 141:94 (1.5:1) | 176:59 (3:1) | 28.2 (<0.0001) | One insert, reduced transmission |
| T-5s-T2 | 170 | 109:61 (1.8:1) | 128:42 (3:1) | 10.74 (0.0011) | One insert, reduced transmission |
| T-1s-T2 | 69 | 43:26 (1.7:1) | 52:17 (3:1) | 5.92 (0.015) | One insert, reduced transmission |
| T-9L-T2 | 63 | 40:23 (1.7:1) | 47:16 (3:1) | 4.45 (0.035) | One insert, reduced transmission |
| T-38s-T2 | 183 | 121:62 (1.95:1) | 137:46 (3:1) | 7.7 (0.005) | One insert, reduced transmission |
| T-12s-T2 | 92 | 58:34 (1.7:1) | 69:23 (3:1) | 7.01 (0.008) | One insert, reduced transmission |
| T-16s-T2 | 79 | 0:79 (0) | 59:20 (3:1) | 237 (<0.0001) | No transmission |
| T-14L-T2 | 102 | 83:19 (4.4:1) | 96:6 (15:1) | 26.67 (<0.0001) | Two inserts, reduced transmissiond |
| T-51L-T2 | 57 | 46:11 (4.2:1) | 53:4 (15:1) | 16.56 (<0.0001) | Two inserts, reduced transmissiond |
T2 seedling populations produced by self-fertilized PIRL6-KD T1 transformants were scored for glufosinate resistance (R) encoded by the selectable marker gene cointegrated with the RNAi construct. S, Glufosinate sensitivity.
Glufosinate resistance was predicted to segregate at a Mendelian ratio of 3:1 resistant (R) to sensitive (S) in each line if fully transmitted to T2 progeny and encoded by a single transgene locus and at 15:1 if the parent T1 harbored two fully transmitted unlinked inserts. Gametophyte lethality would result in significant distortion of these ratios (Feldmann et al., 1997).
χ2 calculations were determined using e-values based on a 3:1 Mendelian ratio for the first nine lines and a 15:1 ratio for T-14L-T2 and T-51L-T2, based on the apparent presence of more than one transgene. P < 0.05 indicates significant segregation distortion from the Mendelian ratio predicted for full transmission.
These lines each produced more than 50% aborted ovules (Fig. 5), consistent with the meiotic segregation of more than one transgene insert.