Phylogeny of Asterids
Asterids
Lamiids Ericales Campanulids Cornales
Cornales Ericales Lamiids: Campanulids: Garryales Aquifoliales Gentianales Apiales Lamiales Dipsacales Solanales Asterales
Lamiales contains about 20 family-level clades and ca. 22, 000 species. After APG, 2003; Judd and Olmstead, 2004, and Soltis et al., 2005 “ Scrophulariaceae” s.l.
A. Mimulus lewisii C. Mimulus cardinalis B. M. lewisii x cardinalis (F1) D-L F2 offsprings
Schemske and Bradshaw, 1999. Proc Natl Acad Sci USA 96(21): 11910-11915. “ Scrophulariaceae” s.l.
A. Mimulus lewisii C. Mimulus cardinalis
A single gene could produce a pollinator shift, and subsequently cause speciation.
Note: the story on the evolutionary genetics of monkey flowers is purely for fun, won’t be on the exam
Bradshaw and Schemske, 2003. Nature 426: 176-178 “ Scrophulariaceae” s.l.
Photo: Yaowu Yuan Photo: Yaowu Yuan Castilleja sp. Mimulus alsinoides
Photo: Yaowu Yuan Photo: Yaowu Yuan
Collinsia sp. Penstemon sp. “ Scrophulariaceae” s.l.
Textbook DVD KRR Penstemon digitalis Note the bilabiate corolla (usually 2 upper lobes and 3 lower lobes); and the didynamous Textbook DVD DLN Stamens –– with two pairs of stamens of Digitalis purpurea unqual length. “ Scrophulariaceae” s.l.
Textbook DVD KRR Textbook DVD KRR & DLN
Antirrhinum najus; snapdragon
Again, note the bilabiate corolla and didynamous stamens
Textbook DVD KRR Penstemon pallidus “ Scrophulariaceae” s.l.
Photo: Yaowu Yuan
Textbook DVD KRR Verbascum sp.; corolla Veronica arvensis; 4 corolla nearly anctinomorphic; 5 lobes, 2 stamens. stamens. A few genera do not follow the “bilabiate (zygomorphic) corolla, didynamous stamens” rule “ Scrophulariaceae” s.l.
Photo: Yaowu Yuan
Castilleja sp.; hemiparasite
Textbook DVD JDS “Scrophulariaceae” s.l. includse a group Orobanche uniflora; of parasitic plants (holoparasites and holoparasite hemiparasites) “ Scrophulariaceae” s.l.
Textbook DVD KRR
Textbook DVD MHS Antirrhinum majus
“Scrophulariaceae” s.l. fruit a many-seeded capsule Linaria macroccana “Scrophulariaceae” s.l. is polyphyletic
This family always has been difficult to characterize by any explicit characters. It seems to have the generalized reproductive morphology of the large order Lamiales, which has ca. 20 families. Recently, Olmstead et al. has determined the family is polyphyletic and it is now being proposed that several families should be recognized.
Scrophulariaceae s.s. Orobanchaceae Veronicaceae (or Plantaginaceae) Calceolariaceae Stilbaceae Phrymaceae
Olmstead e et al., 2001. Am. J. Bot. 88(2): 348-361. “Scrophulariaceae” s.l.
“Scrophulariaceae” s.l. - 269 genera/5100 species, but----
Herbs, shrubs, or small trees. Stem usually round, but sometimes square (e.g., Scrophularia). Leaves alternate or opposite. Flowers zygomorphic (or more rarely actinomorphic). Corolla often bilabiate. 4 stamens, didynamous (occasionally reduced to 2). Carpels 2, connate, ovary superior. Fruit a many-seeded capsule. “ Lamiaceae” (or Labiatae)
Textbook DVD KRR Many members of this family have aromatic oils. These include many culinary herbs and ingredients in perfumes, including sage, oregano, marjoram, rosemary, thyme, basil, lavender.
Lavendula stoechas “ Lamiaceae” (or Labiatae)
Textbook DVD KRR & DLN Photo: Yaowu Yuan
Dracocephalum moldavica Note the bilabiate corolla and Lamium purpureum didynamous stamens “ Lamiaceae” (or Labiatae)
Textbook DVD KRR
Textbook DVD KRR Teucrium canadense Phlomis russeliana Note the opposite (decussate –– square stems) leaf arrangement “ Lamiaceae” (or Labiatae)
Photo: Yaowu Yuan Stachys cooleyae
Note the 4 nutlets, similar to Boraginaceae Textbook DVD JRA
Rosmarinus offcinalis “ Lamiaceae” (or Labiatae)
Textbook DVD KRR & DLN Physostegia virginiana
Note gynobasic style, similar to Boraginaceae
Textbook DVD KRR “ Lamiaceae” (or Labiatae)
“Lamiaceae” - 258 genera/6970 species
Herbs, shrubs, or small trees. Often aromatic. Stem usually square. Leaves opposite and decussate. Flowers zygomorphic. Corolla bilabiate. 4 stamens, didynamous (occasionally reduced to 2). Carpels 2, connate, each with 2 ovules and a false septum between ovules of each carpel; with a gynobasic style arising from between 4 mericarps Fruit a schizocarp forming 4 nutlets. Summary of stamen arrangement
Monadelphous Filaments fused into a tube - Malvaceae
Diadelphous 9 fused at the filaments, 1 free - Fabaceae
Tetradynamous 6 stamens, 4 long, 2 short - Brassicaceae
Didynamous 4 stamens, 2 long, 2 short - Lamiaceae & Scrophulariaceae Connivent anthers anthers held together but not actually fused, surrounding the gynoecium - Violaceae & Solanaceae (Solanum) Parasitic Plants
Textbook DVD WSJ Monotropa uniflora Autotrophic: capable of feeding oneself; For plants, ones that are photosynthetic. Heterotrophic: Referring to oraganisms that do not produce their own food (nonphotosynthetic) and which must then obtain organic compounds from exogenous sources (such as another plant). Many forms Textbook DVD KRR of heterotrophism exist such as saprophytism, Monotropa hypopithys myco-heterotropism, and parasitism. Parasitic Plants
Note: All materials on parasitic plants are from the website www.parasiticplants.siu.edu (presented by Dan Nickrent), unless otherwise indicated. Parasitic Plants
Haustorium: The morphologically modified root which physically connects the parasite to the host. Parasitic Plants
http://www.cas.vanderbilt.edu/bioimages/p/wphle14fr30464.jpg http://www.cas.vanderbilt.edu/bioimages/image /p/phle14wpin-fruit-and-flower56193.htm Phoradendron flavescens; Christmas mistletoe Hemiparasite: A parasite that is photosynthetic (during at least one stage of its life cycle) that obtains water and nutrient from the host xylem. Holoparasite: A nonphotosynthetic parasite that obtains water and nutrients as well as photosynthates from the host. Parasitic Plants
Obligate parasite: A plant that must attach to a host to complete its life cycle. All holoparasites are obigate whereas only some hemiparasites are obligate. Facultative parasite: one that does not require a host to complete its life cycle. Note, however, that in nature, parasitism is nearly always observed. Parasitic Plants
Parasitic Reduction Syndrome (becoming holoparasites):
Textbook DVD WSJ
Loss of leaves - leaves reduced to scales; Small overall size of the plant - no need for large plants to hold leaves; Loss of chlorophyll; Loss of roots - reduced to short, stumpy projections with haustoria; Loss of genes needed for photosynthesis; Rapid DNA divergence in genes that are not lost; Parasitic Plants
Wolfe et al., 1992. Proc Natl Acad Sci USA 89(22): 10648-10652
Wakasugi e et al., 1998. Pl. Mol. Biol. Reporter. 16: 231-241
Note the size of the parasitic plant chloroplast genome is much smaller than tobacco’s –– most genes needed for photosynthesis are lost from the parasite. Parasitic Plants
Note the rapid divergence of chloroplast genes of parasites compared with their non- parasitic relatives
Stefanovic e et al., 2002. Am. J. Bot. 89(9): 1510-1522. Parasitic Plants
Parasitism have evolved perhaps 20 times among flowering plants. In each case the plants have become parasitic on either other plants or fungi. These include 4 families we know: Broginaceae, Scrophulariaceae, Ericaceae, and Orchidaceae.