Table 2.

Analysis of Hieracium FIE Expression, Seed Set, and Germination in Sexual and Apomictic Hieracium Plants Transformed with RNAi Constructs to Downregulate FIE Constitutively (35S:hpHFIE) and in Gametophytes (AtMEA:hpHFIE)

Transgene Copy NumberHieracium FIE LevelNumber of Black Fruit/Capitulum (%)Number Viable Seedlings/Capitulum (%)a
PlantUnpollinatedCross-PollinatedUnpollinatedCross-Pollinated
35S:hpHFIE
    Control Apomict0100b24.7 (75) [n = 20]c17.8 (54)
    5NDd20b18.1 (54) [n = 14]10.4 (31)
    7ND10b1.4 (4) [n = 25]1.0 (3)
AtMEA:hpHFIE
    Control Sexual0100e16.3 ± 6.4 (35) [n = 3]27.0 ± 6.4 (58) [n = 4]10.3 (22)23.0 (49)
    5278e3.0 ± 4.1 (4) [n = 5]23.3 ± 5.9 (31) [n = 4]2.4 (3)14.5 (19)
    14245e0.4 ± 0.9 (1) [n = 5]15.8 ± 2.6 (22) [n = 4]0.06.3 (9)
    18264e1.2 ± 0.8 (2) [n = 5]5.3 ± 1.0 (10) [n = 4]1.0 (2)4.3 (8)
AtMEA:hpHFIE
    Control Apomict0100e23.6 ± 4.0 (73) [n = 5]18.0 (54)
    15.1372e9.6 ± 2.8 (19) [n = 5]1.0 (2)
    17.0448e19.4 ± 3.4 (36) [n = 5]2.8 (5)
    18.0251e5.2 ± 2.4 (19) [n = 5]1.2 (2)
    19.0364e8.6 ± 2.9 (17) [n = 5]0.2 (0.4)
  • APO, apomictic Hieracium; SEX, sexual Hieracium.

  • a All black fruit were plated for germination, and the number germinated was divided by the total number of capitula.

  • b Percentage of expression in leaf relative to the wild type.

  • c n = number of capitula examined.

  • d ND, not determined.

  • e Percentage of expression in ovules relative to the wild type. Hieracium FIE expression was determined by quantitative RT-PCR using cDNA from ovules at stage 6 of capitulum development.