TY - JOUR T1 - Gynoecium diversity and systematics in basal monocots JF - Botanical Journal of the Linnean Society Y1 - 2001 A1 - Igersheim, Anton A1 - Buzgo, Matyas A1 - Endress, Peter K. SP - 1 EP - 65 KW - Acorales, Alismatales, angiosperm systematics, angiospermy, carpels, Dioscoreales, flower evolution, ovules, Triuridales VL - 136 ER - TY - JOUR T1 - Flower structure and development of Araceae compared with alismatids and Acoraceae JF - Botanical Journal of the Linnean SocietyBotanical Journal of the Linnean Society Y1 - 2001 A1 - Buzgo, Matyas SP - 393 EP - 425 VL - 136 N1 - auch Material von verschiedenen Triglochin-Arten und von Maundia untersucht! ER - TY - JOUR T1 - Floral structure and development of Acoraceae and its systematic relationships with basal angiosperms JF - International Journal of Plant Sciences Y1 - 2000 A1 - Buzgo, Matyas A1 - Endress, Peter K. SP - 23 EP - 41 KW - Acoraceae KW - complex organs KW - flower development KW - monocots KW - paleoherbs KW - Piperales AB -

Flower development and anatomy of Acorus calamus and flower anatomy of A. gramineus were studied. Findings were compared with published reports on paleoherbs. Important developmental features include an abaxially median tepal that is initiated first and is similar to a flower-subtending bract and unidirectional flower development with an inversion of organ initiation sequence in the second tepal whorl. The mature gynoecium is largely synascidiate, but early development of carpels is plicate, and the apocarpous portion persists up to anthesis. The carpels form dorsal bulges on the style, enclosing longitudinal intercarpellary slits. The dominance of the synascidiate portion and the apical position of the placenta result from a late and distinct basal elongation of the gynoecium. Stigma, pollen transmitting tract, and ovary are filled with secretion. Secretory papillae are present from the stigma to the placenta; papillae also occur on the rims of the integuments of the ovules. In the uppermost part of the inflorescence, the adaxial floral sectors are reduced in number and structure, and at the apex of the inflorescence, a peloria-like structure is formed. Developmental and morphological similarities seem to be closer between Acorus and Piperales than between Acorus and other magnoliids.

VL - 161 UR - http://www.jstor.org/stable/10.1086/314241 IS - 1 ER - TY - ICOMM T1 - Perianth development in the basal monocot Triglochin (Juncaginaceae) Y1 - 2003 A1 - Buzgo, Matyas A1 - Soltis, D.E. A1 - Soltis, P.S. KW - Juncaginaceae, Alismatales, flower development, perianth, tepal AB - Previous studies on the perianth development of basal monocots argued that the differentiation of tepals and bracts, or of sepals and petals had not fully evolved in Acoraceae and some Alismatales (namely the lineage comprising Juncaginaceae and Potamogetonaceae). Described similarities between Acorus and Triglochin were challenged by two hypotheses:1) What was described as a "flower" in Triglochin is a pseudanthium (an inflorescence looking like a flower), and the "perianth" consists of bracts;2) Triglochin does not have an abaxial outermost "tepal" reminiscent of a flower-subtending bract, but flower development commences with two lateral (or adaxial) tepals.We illustrate the flower development of Triglochin maritimum in the framework of other Juncaginaceae (Triglochin, Maundia, Tetroncium). The developmental genetics of the perianth in basal monocots is discussed with respect to "organ identity" and "homology". Up to now, the two challenging hypotheses are not supported by our data. Triglochin has no pseudanthium, and the perianth consists of tepals. Flower development is unidirectional with a leading abaxial tepal. However, there are putative reductions in the flowers within a single inflorescence, within the genus Triglochin, as well as the entire family Juncaginaceae. N1 - Abstract "Monocots III" conference, session "Basal Monocots" (organized by Graham, S.W.) ER - TY - ICOMM T1 - B-Class organ identity in basal monocots Y1 - 2002 A1 - Buzgo, Matyas A1 - Soltis, Douglas E. A1 - Soltis, Pamela S. A1 - Hauser, Bernard A. A1 - Johansen, Bo KW - flower development, MADS-box genes, monocots, organ identity, RT-ISPCR AB - In basal monocots (e.g. Acoraceae, Alismatales s. APG 1998) it is difficult to unravel the ancestral features if floral morphology by comparison with their outgroups (magnoliids) and more derived clades of monocots. Two general types occur:1) flowers with distinct sepals and petals, often two or several whorls of stamens and carpels, and intercarpellary nectaries (e.g. Alismataceae, Butomaceae, Hydrocharitaceae, Tofieldiaceae);2) flowers with an undifferentiated perianth consisting of tepals, one or two whorls of carpels, which are often centrally fused and lack intercarpellary nectaries (e.g. Acoraceae, Araceae, Aponogetonaceae, Juncaginaceae, Potamogetonaceae, Scheuchzeriaceae).Type 1 is most similar to flowers in magnoliids such as Annonaceae, Aristolochiaceae, and monocots such as Dioscoreaceae and Liliaceae, whereas type 2 is similar to magnoliids such as Saururaceae and Chloranthaceae. In current phylogenetic analyses Acoraceae are sister to all other monocots, and Aponogetonaceae are basal within Alismatales. Therefore, the second type may represent a suite of morphologically plesiomorphic character states. However, because these basal clades stand on long branches, the actual features may as well have undergone extensive anagenesis, and therefore represent autapomorphies.To elucidate floral evolution in these basal monocots, a better understanding of perianth organ identity, differentiation and development is critical. Some of the genes responsible for the differentiation of the perianth are transcription factors of the MADS-box gene family, known as B-class genes: orthologs of APETALA3 and PISTILLATA in Arabidopsis, and DEFICIENS and GLOBULOSA in Antirrhinum. Expression of B-class genes in perianth organs of basal monocots exhibiting a morphologically undifferentiated perianth would be consistent with a petaloid developmental program for these organs, even though the perianth may appear bracteolar or sepalous in later stages of development. B-class genes in the genus Triglochin (Juncaginaceae) are characterized and the application of reverse transcription in situ PCR (RT-ISPCR) is discussed. N1 - abstract "Botany 2002" conference ER - TY - JOUR T1 - Perianth development in the basal monocot Triglochin maritima (Juncaginaceae) JF - Aliso Y1 - 2006 A1 - Buzgo, Matyas A1 - Soltis, Douglas E. A1 - Soltis, Pamela S. A1 - Kim, Sangtae A1 - Ma, Hong A1 - Hauser, Bernard A. A1 - Leebens-Mack, Jim A1 - Johansen, Bo SP - 107 EP - 125 KW - APETALA3 KW - basal angiosperms KW - fading borders KW - gene expression pattern KW - Juncaginaceae KW - MADS-box gene KW - monocots KW - organ identity KW - Triglochin AB -

Basal monocots exhibit considerable variation in inflorescence and floral structure. In some cases, such as Triglochin maritima, it is not clear whether the lateral and terminal structures of the inflorescence are flowers or pseudanthia, or where the limits between flowers and inflorescence lie. To address these questions, morphological studies were carried out, and the results show that in T. maritima both terminal and lateral structures are flowers, not pseudanthia. The terminal flower of T. maritima develops from the apical inflorescence meristem, suggesting that the apical meristem identity changes from ‘‘inflorescence’’ to ‘‘flower’’ during inflorescence development. In addition, distal flowers of T. maritima are reduced, and there is no distinct flower-subtending bract; instead, the perianth develops unidirectionally, resulting in an abaxial-median bract-like tepal and bilaterally symmetrical flowers, similar to those of other basal monocots, such as Aponogeton and Acorus. It is possible that the leaf primordium changes its positional homology from ‘‘flower-subtending bract’’ to ‘‘tepal.’’ Therefore, in some basal angiosperms with abbreviated development of lateral flowers the demarcation of the flower vs. the inflorescence is ontogenetically ambiguous. In situ hybridization experiments show that a putative ortholog of the B-class gene APETALA3 / DEFICIENS is expressed in developing stamens and carpels, and may also be expressed in the shoot axis of the very young inflorescence. This expression pattern seems to be consistent with the gradual transition between inflorescence and flower that was observed morphologically.

VL - 22 UR - http://curis.ku.dk/ws/files/13860089/PERIANTH_DEVELOPMENT_IN_THE_BASAL_MONOCOT.pdf ER -