Table I. Characteristics of parental and mutant rice lines.
Dehulled grain weight, starch content, weight-average Mr, and Z-average radius of amylopectin gyration are shown for ss3a ss4b double mutant rice lines (#2012 and #2013), the parental mutant lines ss3a (e1) and ss4b (e8 and e14), and the wild-type rice, cv Nipponbare. Asterisks indicate significant differences between cv Nipponbare and mutant lines (P < 0.05, Student’s t test). Dashes, Not analyzed.
| Line | Genotype | Grain Weighta | Starch Contentb | Mwc | Rzd |
|---|---|---|---|---|---|
| mg | ×108 g | nm | |||
| cv Nipponbare | Wild type | 20.3 ± 0.3 (100) | 16.9 ± 1.2 (83.3) | 43.7 ± 4.1 (100.0) | 665.4 ± 26.9 |
| e1 | ss3a | 20.8 ± 0.2 (102) | 16.3 ± 1.1 (78.4) | 10.4 ± 0.5* (23.8) | 451.6 ± 8.9* |
| e8 | ss4b | 21.2 ± 0.2 (104) | 18.1 ± 0.6 (85.4) | 18.9 ± 1.4* (43.2) | 474.9 ± 16.8* |
| e14 | ss4b | 17.8 ± 0.3* (85)e | 12.2 ± 1.1 (68.5) | – | – |
| #2012 | ss3a ss4b | 17.4 ± 0.1* (86) | 9.9 ± 0.4* (56.9) | 5.1 ± 1.3* (11.7) | 287.8 ± 9.2* |
| #2013 | ss3a ss4b | 16.6 ± 0.2* (81) | 9.4 ± 1.0* (56.6) | – | – |
Values shown are means ± se of 50 seeds, with percentages of the wild type given in parentheses. bValues shown are means ± se of three seeds, with percentages of grain weight given in parentheses. cWeight-average Mr, with percentages of the wild type given in parentheses. dZ-average radius of gyration. eNote that the grain weights of e14 (−/−) and e14 (+/+), which were both segregated from the heterozygous parent e14 (+/−), were 85% and 78%, respectively, of that of the wild type. This indicates that the reduction in grain weight in e14−/− did not result from the insertion of Tos17 into the SSIVb gene.