In Arabidopsis, different combinations of ABC organ identity proteins interact in the presence of SEPALLATA (SEP) proteins to regulate floral organ differentiation. Ectopic expression of SEP3 in combination with class A and B or B and C genes is sufficient to homeotically convert vegetative leaves into petal-like organs and bracts into stamen-like structures, respectively. Recently, it has been...

Gibberellins (GAs) are plant hormones that regulate most plant life cycle aspects, including flowering and fruit development. Here, we demonstrate the implication of GAs in ovule development. DELLA proteins, negative GA response regulators, act as positive factors for ovule integument development in a mechanism that involves transcription factor ABERRANT TESTA SHAPE (ATS). The seeds of the dell...

Doubled haploids of carnation (Dianthus caryophyllus L.) were obtained by pseudofertilized ovule culture. Emasculated ̄ower buds of carnation were pollinated with pollen inactivated by Xray irradiation. After 2±3 weeks, the ovaries were explanted and were cultured on solid MS medium containing 2 mM NAA, 2 mM BAP and 6% sucrose. Regenerated plants(R0) were morphologically different from the moth...

Pre-embryogenic calli were obtained from the culture of fertilized immature ovules of muscadine ( Vitis rotundifolia Michx.) and seedless bunch grapes ( Vitis vinifera L.) on: 1) Murashige & Turcker (MT, 1969) basal medium supplemented with 4.4 μM 2, 4-D (2, 4-dichlorophenoxyacetic acid) and 1 μM BA (6-benzyladenine) with 6.0% (w/v) sucrose; 2) Chee and Pool (CP, 1978) basal medium supplemented...

Angiosperm ovules consist of three proximal-distal domains – the nucellus, chalaza and funiculus – demarcated by developmental fate and specific gene expression. Mutation in three paralogous class III homeodomain leucine zipper (HD-ZIPIII) genes leads to aberrations in ovule integument development. Expression of WUSCHEL (WUS) is normally confined to the nucellar domain, but in this triple mutan...

Arabidopsis (Arabidopsis thaliana) SUPERMAN (SUP) plays a role in establishing a boundary between whorls 3 and 4 of flowers and in ovule development. We characterized a Petunia hybrida (petunia) homolog of SUP, designated PhSUP1, to compare with SUP. Genomic DNA of the PhSUP1 partially restored the stamen number and ovule development phenotypes of the Arabidopsis sup mutant. Two P. hybrida line...

The earliest known ovules in the Late Devonian (Famennian) are borne terminally on fertile branches and are typically enclosed in a cupule. Among these ovules are some that have terete integumentary lobes with little or no fusion. Here, we report a new taxon, Latisemenia longshania, from the Famennian of South China, which bears cupulate ovules that are terminal as well as opposite on the ferti...

KANADI (KAN) transcription factors promote abaxial cell fate throughout plant development and are required for organ formation during embryo, leaf, carpel and ovule development. ABERRANT TESTA SHAPE (ATS, or KAN4) is necessary during ovule development to maintain the boundary between the two ovule integuments and to promote inner integument growth. Yeast two-hybrid assays identified ETTIN (ETT,...