Scan. 2. Thus, measuring the size of the meristem is only useful if accompanied by measurements of the size of the primary branch primordia. Content Guidelines J. Agric. doi: 10.1086/428701, Bommert, P., Lunde, C., Hardmann, J., Vollbrecht, E., Running, M., Jackson, D., et al. In addition, the vascular (hydraulic) architecture of the inflorescence affects the ability of the plant to supply developing seeds with water and photosynthate. – Taxon 45: 453‐460. J. Bot. A floret consists of two bracts, the lemma and the palea, which enclose the grass flower. (2007), Saarela et al. Regulation of leaf initiation by the terminal ear1 gene of maize. 2, 175–194. Res. Kellogg, E. A. Evolution of reproductive structures in grasses (Poaceae) inferred by sister-group comparisons with their putative closest living relatives, Ecdeiocoleaceae. Our mission is to liberate knowledge. N. Z. J. Bot. 31, 193–201. (2010, outgroups), Quintanar et al. When the two ranks are separated by an angle of approximately 180°, we refer to the phyllotaxis as “distichous.” Inflorescences with more than two ranks are called spiral, polystichous, or having multiple orthostichies. The family Poaceae has a peculiar inflorescence of small spikes (spikelets) organised in panicles or spikes that are usually simply and improperly referred to as spike and panicle. Brachyelytrum erectum (Figure 3). Vouchers of representative specimens are listed in Table 2. The floral units of this species are clearly arranged in a spiral (Figures 1D,E). LeRoux, L. G., and Kellogg, E. A. Figure 12. 24, 706–713. (2010), and Grass Phylogeny Working Group II, 2012. Phyllotaxis: A Systematic Study in Plant Morphogenesis. (2009). 71, 523–532. Functional associations of floret and inflorescence traits among grass species. Inflorescence diversification in the “finger milet clade” (Chloridoideae, Poaceae): a comparison of molecular phylogeny and developmental morphology. Taxonomy, phylogeny, and inflorescence development of the genus Ixophorus (Panicoideae: Poaceae). Poaceae - Poaceae - Characteristic morphological features: Although grasses superficially resemble other plants, most notably the rushes (family Juncaceae) and sedges (family Cyperaceae), these similarities are far outweighed by the numerous less-conspicuous differences in the structure and arrangement of reproductive parts, pollen development and structure, chromosome structure, and … Within the grasses, even if the inflorescence meristem produces primordia in multiple orthostichies or parastichies, higher order meristems (primary, secondary, tertiary branches) always produce two ranks of branch or spikelet primordia; these may or may not be separated by angles of 180°. Nardus stricta (Figure 4A). *Correspondence: Elizabeth A. Kellogg, Department of Biology, University of Missouri-St. Louis, One University Boulevard, St. Louis, MO 63121, USA e-mail: email@example.com, Front. The subfamily Anomochlooideae is sister to the remainder of the grasses, and includes the genera Streptochaeta and Anomochloa [Grass Phylogeny Working Group II, 2012; (GPWG II)], neither of which produces spikelets. im, inflorescence meristem; pb, primary branch; b, bract. Appl. doi: 10.1111/j.1365-2435.2010.01704.x, Davis, H. G., Taylor, C. M., Lambrinos, J. G., and Strong, D. R. (2004). doi: 10.3732/ajb.92.4.565. doi: 10.3732/ajb.92.9.1432. This type of inflorescence is found in genus Euphorbia of family Euphorbiaceae; also found in genus Pedilanthus of the family. In representatives of both families, the inflorescence meristem produces lateral structures in a spiral. Bot. J. Phytoliths are plant-produced micro silica bodies which can, in some cases, have a diagnostic morphology that can be distinguished among taxa; in particular, phytoliths in the Poaceae family can have taxonomic value in archaeological contexts and natural sediments (Twiss et al., 1969; Wang and Lu, 1993; Piperno, 2006). Alternatively, distichous phyllotaxis could be a synapomorphy for Pooideae, and could correlate with the ecological expansion of the group to temperate climates (Grass Phylogeny Working Group, 2001; Edwards and Smith, 2010; Grass Phylogeny Working Group II, 2012). 60, 25–37. The earliest stage we have observed shows a large number of presumed branch primordia arising from a broad meristem (Figure 1F). Missouri Bot. An Arabidopsis F-box protein acts as a transcriptional co-factor to regulate floral development. The more proximal bracts subtend staminate flowers, whereas the distal bracts subtend pistillate flowers, each consisting of a single gynoecium. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Ann. 86, 354–366. The inflorescence of Joinvillea is large, up to 40 cm long, and multibranched. Fraser, J., and Kokko, E. G. (1993). doi: 10.1242/dev.048348, Cresswell, J. E., Krick, J., Patrick, M. A., and Lahoubi, M. (2010). Anomochloa, in contrast, is reported to be primarily distichous (Judziewicz and Soderstrom, 1989), although again definitive data are not available. U.S.A. 101, 13804–13807. (B,C), apo1 mutant. The inflorescence of grasses has been classified variously. What is the difference between Racemose and Cymose? Many proteins are known to control the architecture of inflorescences in the grasses (Bommert et al., 2005b), and there are good candidate genes for control of the phenotypes described here. |, http://www.mobot.org/MOBOT/research/APweb/. The main groups of inflorescences are distinguished by branching. 168, 181–191. Reinheimer, R., Zuloaga, F. O., Vegetti, A. C., and Pozner, R. (2009). A. Nat. In addition, the interaction of LFY and UFO also appears to be important in bract suppression in Arabidopsis, which may have a direct or indirect effect on phyllotaxy (Hepworth et al., 2006). Branch meristems form in the axils of these bracts (Figure 9F). (1996). The aerodynamics and efficiency of wind pollination in grasses. 58, 119–125. (2006). Another term often used in inflorescence description is peduncle, defined as the stalk of a cluster of spikelets (Gould, 1978). Phylogenet. Amer. Dorsal compression is most often found in spikelets of Panicum and related genera where a sterile floret is borne below the perfect one. A spikelet consists of two (or sometimes fewer) bracts at the base, called glumes, followed by one or more florets. J. Bot. Inflorescence development in the grass family (Poaceae) begins when the shoot apical meristem converts from its vegetative state, producing leaves on its flanks, to an inflorescence meristem. Dev. Landes, A., and Porter, J. R. (1990). Taylor, S., Hofer, J., and Murfet, I. J. Bot. doi: 10.1111/j.1095-8339.2012.01283.x, Salariato, D. L., Zuloaga, F. O., Giussani, L. M., and Morrone, O. The morphology and developmental genetics of the shift in phyllotaxis have been studied extensively in maize and rice. doi: 10.2307/3298585, Grass Phylogeny Working Group II. Most often the palea fits within the enrolled edges of the lemma and does not often offer distinguishing characteristics. Am. In this study, we show that Brachyelytrum, the genus sister to all other Pooideae has spiral phyllotaxis in the inflorescence, but that in the remaining 3000+ species of Pooideae, the phyllotaxis is two-ranked. The result is a multi-ranked inflorescence with a distinct “front” (bearing branches) and “back” (with no branches) (Figure 3E). Aphelia, however, is clearly distichous; this appears to be a derived state. Thus, “distichous” is a subset of “two-ranked.” The only data for subfamily Danthonioideae come from Chionochloa macra, in which the primary branch primordia are distichous (Martin et al., 1993). doi: 10.1111/j.1759-6831.2010.00087.x. In some cases, the inflorescence meristem ultimately converts to a spikelet meristem and in others it simply terminates without further differentiation. Cresswell et al. Based on phytolith taxonomy and morphology, phytolith analysis has been proven to be a reliable tool in understanding the taxonomy and evolution of plants (Prychid et al., 2003; Rudall e… Plant Sci. 170, 393–404. Genetics 184, 343–350. doi: 10.1093/annbot/58.4.569, Sundberg, M. D., Orr, A. R., and Pizzolato, T. D. (2008). Racemose inflorescence of monocots: structural and morphogenetic interaction at the flower/inflorescence level. The evolution of nuclear genome structure in seed plants. doi: 10.1242/dev.01671, Bommert, P., Satoh-Nagasawa, N., Jackson, D., and Hirano, H. Y. The typology developed by Troll was followed to describe inflorescence structures for 15 species of Spartina. To determine the phylogenetic patterns that will drive investigations of gene evolution, we analyze the developmental fate of the inflorescence meristem in grasses, and consider the phyllotaxis of the primary branch meristems and whether the meristem converts to a spikelet or simply aborts. Pflanzen 69, 363–431. The inflorescence is the arrangement of flower on the stem. Pflanzen 66: (1991) 297-311 Gram, 1961 K. Gram, The synflorescence of the grasses Bot. In grasses, as in many other flowering plants, the phyllotaxis of lateral structures in the inflorescence may continue the same phyllotactic pattern as the leaves, or it may change. Quantitative variation in maize kernel row number is controlled by the FASCIATED EAR2 locus. Likewise, in tribe Andropogoneae, Bothriochloa bladhii, Sorghum bicolor, and Zea mays produce branches in a spiral (Bonnett, 1940; LeRoux and Kellogg, 1999; Brown et al., 2006), but the fate of the inflorescence meristem differs between species. New grass phylogeny resolves deep evolutionary relationships and discovers C4 origins. doi: 10.1016/j.ydbio.2005.03.016, Ikeda-Kawakatsu, K., Yasuno, N., Oikawa, T., Iida, S., Nagato, Y., Maekawa, M., et al. In Oryza sativa, the vegetative apex has an aspect ratio of about 1.0, and this drops to 0.4 or even 0.2 in the transition to flowering (Takeoka et al., 1989). Harder, L. D., and Prusinkiewicz, P. (2013). Illustration of a bristlegrass (Setaria) spikelet. Thus, the primary phyllotaxis of the inflorescence is different, even though subsequent branching appears to be morphologically similar. (A) wild type. Sokoloff et al. Willdenowia 9, 161–167. 193] See list of 19 genera in 7b Poaceae 7 (1999). In Gramineae/Poaceae, the inflorescence is . 94, 92–100. Macroevolution of panicoid inflorescences: a history of contingency and order of trait acquisition. The grass flower consists of a vestigial perianth called lodicules and the stamen and pistil. Nonetheless, our data hint that meristems in Pooideae may be somewhat smaller than those in taxa with spiral phyllotaxis. Outgroups.
Seed Dormancy in Grasses. Phaenosperma globosa (Figures 4B,C).
2020 inflorescence of poaceae