Parasitic Flowering Plants

Glossary (* marked words) Epiphyte: a non-parasitic plant, moss or lichen phy- sically supported by another plant. Epicotyl: the embryonic shoot above the cotyle- Achene: a small, dry, indehiscent, and single-seeded dons - develops into the primary stem. fruit. Exocarp: the outer layer (skin) of the fruit wall. Adventitious root: a root developing from stem tissue Exophyte: that part of a parasite which is visible in contrast to lateral roots which are ramifications outside the surface of the host. from other roots. Fynbos: a 00-200 km broad coastal vegetation Amyloplast: a special kind of starch-filled plastid zone between Clanwilliam and Port Elisabeth in (starch grain) bounded by a double membrane. South Africa. Fynbos is characterized by a Medi- Anticlinal: cell walls that are oriented perpendicu- terranean climate with winter rain, summer drought lar to the surface of the organ. and fires in the west but less seasonal variation in Autolysis: enzymatic self-digestion. the east. The Fynbos has more than 7.000 ferns and Apomixis: a kind of asexual reproduction where the flowering plants and is dominated by Proteaceae, seed develops without a preceding fertilization of the Ericaceae and bulbous plants. egg cell by a sperm cell. The offspring will be geneti- Gametophyte: the haploid generation forming ga- cally identical to the parent. metes, i.e., sexual cells. Autophytes: photosynthetic plants able to manufac- Hypocotyl: the first stem bearing the cotyledons. ture or take up all necessary nutrients and water Inferior ovary: an ovay placed below the insertetion without help from other organisms. of perianth and stamens (epigyneous flower). C3- and C4-photosynthesis: see Box 8, page 30. Maps: The green areas represent a rough guide to cfr.: (confer) is used to indicate the species name the geographical limits of the families and the given is the most likely but not fully verified. boundaries are in several cases somewhat arbitrary. Chalaza: The region of the ovule where the vascu- The maps give no indication whether the family is lar strand from the placenta is ending. It is often evenly spread within the area or occurs more scat- opposite the micropylar end. See Box 4, page 30. tered. The maps are compiled from several sources Cuticular folds: ridges formed on the cuticle. About including local floras when available. the cuticle, see Box 6 page 273. Meristem: Tissue or cell layer with cell divisions (mitosis). Cystoliths: concretions extending from the inside of Mesocarp: middle layer of the fruit wall. cell walls, usually consisting of calcium carbonate. Mesophytes: plants growing under average humidity ha- Dioecious: unisexual plants with unisexual flowers. ving no particular structural adaptations to either the Elaiosome: an appendage to the seeds rich in li- most humid or driest climates. pids and proteins that is attractive for animals, Millet: common name for a number of small seeded particularly ants, which disperse the seeds. grains including pearl millet (Pennisetum glau- Endemic: see Box 5, page 82. cum), foxtail millet (Setaria italica), and finger Endocarp: Inner layer of the fruit wall. millet (Eleucine coracana). Endoplasmic reticulum: a network of tubules, vesic- Monoecious: plant with unisexual flowers where both les and cisternae in living plant and animal cells. types occur on the same individual. There are two types, smooth without and rough Monotypic: a family or genus containing only one with ribosomes associated with protein synthesis. genus or species, respectively. Endosperm: develops by cell divisions after fusion Mycelium: the underground part or vegetative bo- of a male nucleus with the two central nuclei of the dy of a fungus consisting of thin tubular often embryo sac and serves as the main nutrient source multinucleate cells called hyphae. for the developing embryo. See Box 4, page 30. Mycorrhiza: means ‘fungus root’, a symbiotic rela-

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tionship between a fungus and a root of a vascular Sclerenchyma: mechanical supporting tissue of usu- plant. There are different types of mycorrhizal re- ally dead lignified (woody) cells such as wood fibres. lationships depending on which tissues of the host SEM: scanning electron micrograph, a photograph roots are colonized, and if the hyphae penetrate the taken with a scanning electron microscope. cells walls or not. Serpentine soil: a soil rich in magnesium and heavy Osmosis/Osmotic gradient: causes water to move metals but low in calcium and essential nutrients. along a concentration gradient and is established s.l.: (sensu lato) indicates the widest possible mea- where two compartments are separated by a semi- ning of a taxon, e.g., Raffleciaceae s.l. includes the permeabel membrane. The membrane only al- families Apodanthaceae, Mitrastemonaceae, and lows ions or molecules up to a certain size to pass, Cytinaceae recently segregated from Rafflesiaceae. and the result is that concentration differences can Sporophyte: the diploid generation producing spores build up between the two compartments. Solute or spore like cells. In seed plants the spores are concentration therefore has influence on water called pollen and megaspore (3 and 9 in Box 4). potential*. Staminodium: a sterile stamen, often rudimentary. Ovary: that part of a flower formed by the carpels and Starch sheath: a starch containing tissue of stems housing the ovules. See Box 4, page 30. corresponding to the endodermis in roots but lack- PAS: periodic acid-Schiff’s reagent, that stains car- ing Casparian strips (Box 7). bohydrates red, including non-lignified cellulosic Statoliths: plastids filled with starch (amyloplasts*) cell walls. Often used in combination with aniline- which position themselves in root cap cells accord- blueblack which stains proteins (e.g. the living pro- ing to gravity. They thereby exert different pres- toplasm) dark blue. sures on the internal membrane system (endoplas- Periclinal: cell walls that are oriented parallel to the matic riticulum) of the cells. Increased pressure surface of the organ. activates synthesis of hormones and finally lateral Periderm: a tissue, often called bark, consisting roots of first order tends to grow in the direction of mostly of dying or dead cork cells (phellem) on gravity. the outside and living secondary cortex (phello- Stomata: the small apertures in leaves where the ope- derm) on the inside of a cork cambium (phello- ning (aperture) can be adjusted by form changes of gen). Compare to vascular cambium*. the two guard cells which surround it. Phloem: a tissue of several living cell types of im- Stomatal conductance: the speed with which gasses portance for the translocation of photosynthates. such as water vapour diffuses through stomata*, Sieve tube members have lost the nuclues but life given in mm/sec. processes are governed from the companion cells. TEM: transmission electron micrograph, a photograph See Box 3, page 9. taken with a transmission electron microscope. Phyllode: a winged, flattened petiole functioning as Tetraploid: a plant with four sets of chromosomes a leaf. (Plylloclade, a similarly flattened stem). rather than the normal two sets (diploid). Plasmodesmata: membrane-lined communication Tyloses: protrusions developed through pores in the channels between cells. See Box 7, page 296. cell walls from parenchyma cells into tracheary ele- Plastids: a group of cell organelles bounded by two ments of the xylem. They thereby block for transport cell membranes. The most important are the chlo- and may sometimes be a repair mechanism after xylem roplast , the seat of photosynthesis and the amylo- injury but in other species they form regularly. plast storing starch. Uniseriate: a single file of cells. Pteridophytes: lower vascular plants including plant Vacuoles: non-protoplasmic, membrane-bound com- groups such as club mosses (Lycopodiaceae), ferns ments in the cell which function mainly as storage or (Pteridophyta), horsetails (Equisetales) and others. excretion containers.

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