Fig. 5: Floral phenotypes in the wild type and grp20 mutants.
a, The floral phenotypes in the WT and grp20 mutants. The yellow letters and numbers at the top right of each panel indicate the corresponding organ and number in the flower. P, petal; S, stamen. In WT flowers, there were four petals and six stamens; in grp20-1 flowers, four to five petals and five to eight stamens; and in grp20-2 flowers, one to five petals and four to seven stamens. Yellow arrows and asterisks indicate extra organs (petal or stamen, arrows) and chimeric organs (fusion of petal and stamen tissues, asterisks), respectively. White arrows indicate abnormal carpels. Scale bar = 1 mm. b, Number of floral organs in flowers of different genotypes (flower counts: WT, 80; grp20-1, 85; grp20-2, 90; comple., 95). In grp20 mutants, there were three to five sepals, two to six petals, two to eight stamens and two to four carpels whereas the wild type had four sepals, four petals, five to six stamens and two carpels. Data are presented as the fraction (ratio) of the floral organ number to the total organ count in b and c, and detailed flower counts are shown in Supplementary Table 5. For examples, all 80 flowers of the WT have 4 sepals; therefore, the fraction of 4 in the WT is 1 (80/80). However, among 85 flowers of grp20-1, 74, 9 and 2 flowers have 4, 5 and 6 sepals, respectively. Therefore, the fractions of 4, 5 and 6 sepals in grp20-1 are 0.870 (74/85), 0.106 (9/85) and 0.024 (2/85), respectively. The P values are shown in the following order (from left to right) in b and c: WT versus grp20-1, WT versus grp20-2 and WT versus complementation. For ‘Sepal’, P = 0.0167 and 0.01; for ‘Petal’, P = 0.0063 and 0.0082; for ‘Stamen’, P = 0.0014 and 0.0045; for ‘Carpel’, P = 0.013 and 0.018. c, The total organ number in a WT flower, grp20 mutants and the complementation line (flower counts: WT, 60; grp20-1, 75; grp20-2, 48; comple., 66); 35% and 28% of the flowers in grp20-1 and grp20-2, respectively, showed abnormal organ numbers. From left to right, P = 0.007 and 0.0025. In b and c, ‘Comple.’ is the complementation line with ProGRP20::GRP20-YFP in the grp20-1 background. Data are presented as mean ± s.d. for indicated flower counts; *P < 0.05; **P < 0.01, two-sided Student’s t-test. d, The floral organ identity phenotypes of grp20 mutants. The normal petal and stamen in the WT are shown in the first two panels. Chimeric organs between the petal–stamen, stamen–carpel and sepal–carpel in the grp20 mutants are shown in the other four panels. Scale bars = 500 μm. The yellow asterisks point to specific fused organs.
