Presentation is loading. Please wait.

Presentation is loading. Please wait.

The most important thing to remember when using this (or any other) glossary is that just because some aspect of an organism is dignified by a sesquipedalian.

Similar presentations


Presentation on theme: "The most important thing to remember when using this (or any other) glossary is that just because some aspect of an organism is dignified by a sesquipedalian."— Presentation transcript:

1 The most important thing to remember when using this (or any other) glossary is that just because some aspect of an organism is dignified by a sesquipedalian term, this by no mean signifies that it is "real". Definitions should as far as possible follow current usage, rather than etymology or original definitions. However, current usage may not be consistent, and this is one of the major failings of botanical terminology. As Rickett (1954 p. 2; emphasis in original) noted, "To be uncertain whether "glabrous" means "free from hairs and roughness" or only "free from hairs" is as bad as if pi should stand sometimes for the ratio of a circle to its diameter and sometimes for something else; or as if Cu meant sometimes "copper" and sometimes "brass". Yet this is the state of affairs in botany today". Over forty years later, this is still true, but we should be attempting to reach consensus here, too. From the Introduction to the Glossary at APweb

2 Inflorescence Types Includes Inflorescence, Florescence, and Flower Shoots Multiple criteria used to define a particular type Defined by Minimal Inflorescence Unit (MIU), usually the Florescence Defined by how MIUs are borne on the Reproductive Shoot, the Inflorescence Defined as determinate or indeterminate in two senses Defined by developmental mechanism and by final result Here, all nodes have lateral determinate organs so they can more easily be recognized as nodes Inflorescence Subflorescence Florescence Flower

3 Inflorescence Types Two somewhat independent criteria of Determinacy of Inflorescence The first sense: Behavior of the Florescence SAM Defined as determinate if Florescence SAM converts to Flower SAM Defined as indeterminate if it continues to makes florescence phytomeres Figures should indicate if there is a terminal flower or no terminal flower The second sense: Order of Flower Opening Defined as determinate if top/distal/central flowers open first; defined as indeterminate if bottom/proximal/peripheral flowers open first Figures should indicate the order of opening by the size of the flower. Smaller flowers are understood to open later than, after than, larger flowers. Probably Illegal In – In Det – In In – Det Det - Det

4 Figure 10-13 Walters and Keil In-In In-In Det-In Det-In Det-In Det-In In-In Det-Det Det-ps In Det-Det Det-Det Det-Det Blue, Indeterminate or Determinate in the First Sense Red, Indeterminate or Determinate in the Second Sense This is a compound raceme This is a panicle Simple Compound Dichasium

5 Simple Raceme = a Florescence Pedicelled Flowers Compound Spike contains a Subflorescence Spikes arranged as a Raceme Indeterminate (in the first sense) Types of Reproductive Shoots Primary and Secondary Florescence SAMs ( ) remain indeterminate Probably always indeterminate in the second sense Simple Spike = a Florescence Sessile Flowers Compound Raceme contains a Subflorescence Racemes arranged as a Raceme Simple Compoundness: 2 o a complete copy of the 1 o Peduncle Rachis Pedicel Bract Cauline Leaf

6 Probably always indeterminate in the second sense Simple Corymb Raceme with differentially-elongate pedicels, resulting in round- or flat-topped florescence Compound Corymb Contains a Subflorescence Corymbs arranged in a Corymb Indeterminate (in the first sense) Types of Reproductive Shoots Primary and Secondary Florescence SAMs ( ) remain indeterminate Simple Compoundness: 2 o a complete copy of the 1 o Peduncle Rachis Pedicel Bract Cauline Leaf

7 Determinate (in the first sense) Inflorescence Types Superficially no Primary Shoot because of very short internodes Fascicles with pedicelled flowers; pedicels are flexis Glomerules with sessile flowers Probably always indeterminate in the second sense Bract A foreshortened Raceme A foreshortened Spike

8 Determinate (in the first sense) Inflorescence Types Superficially no Primary Shoot because of very short internodes Umbel with pedicelled flowers inserted into a small head-like receptacle Pedicels (and rays) are stiff The second sense of determinacy: top/distal/central flower opens first Simple Umbels Compound Umbel A foreshortened Corymb Umbels arranged in an Umbel in the second sense This is not branchable, unlike compound spikes, racemes, and coryms (2 o peduncles)

9 LODs within and subtending Inflorescences 1) if subtending and one per flower, it is a floral (or subfloral) bract 2) if one and subtending a florescence, then an inflorescence bract; origin a cauline leaf subtending an axis of bractless flowers 3) if several and subtending a florescence, then collectively an involucre; origin a foreshortened axis of flowers with retained bracts (Umbel) or origin a foreshortened subflorescence-containing

10 Other Inflorescence Types Spadix Spike with fleshy rachis Hypanthodium Cyanthium Spikelet Compressed spike Poaceae Head/Capitulum Asteraceae

11 Determinate Inflorescence Types The Simple Cymes (Often) Opposite Phylotaxy in a Florescence Shoot; Determinate in both senses 1. Nonbranching Fundamental Unit, a Dichasium or a Cyme; Unit of Three 2. Central Flower SAM aborts; Dichotomously Branching 3. One Axillary Flower SAM aborts; Zig-zag, secund, depending on phylotaxy The opposite two bracts mark the last Florescence Node and axillary SAMs 1 2 3 At this point an Indeterminate (Florescence) SAM At this point a Determinate (Flower) SAM Dichasium or if sessile then a Cyme Axillary (Flower) SAM

12 Determinate Inflorescence Types The Non-Simple Cymes (Usually) Opposite Phylotaxy in a Florescence Shoot and Determinate in the second sense 1.Nonbranching Fundamental Unit, a Dichasium 2. One Axillary SAM is a functioning Florescence SAM 3. Both Axillary SAMs are functioning Florescence SAMs The opposite two bracts mark the last Florescence Node and axillary SAMs 1 2 3 Present Indeterminate (Florescence) SAM Dichasium or if sessile then a Cyme

13 Determinate Inflorescence Types The simple and compound Cymes Higher-order compound inflorescences are usually dichotomously branched, hence the term dichasium for the responsible minimum unit Pedunclulate Dichasiums arranged Dichasiums arranged as a Dichasium as a Cyme (Peduncled secondaries) (Sessile secondaries) Peduncle

14 Simple Twice Compound Compound Dichasiums/Cymes have a Different Kind of Compoundness This kind is the same as seen in compound leaves 0 1 2

15 Determinate Inflorescence Types Compound Cymes made from differential outgrowth Higher-order compound inflorescences from development of axis on the same side of the primary axis decussite distichous Compound Dichasium Helicoid Cyme Drepanium Compound Monochasium

16 Determinate Inflorescence Types Compound Cymes made from differential outgrowth Higher-order compound inflorescences from development of axis on alternating sides of the primary axis distichous Scorpiod Cyme Compound Dichasium decussite Rhipidium Compound Monochasium

17 Determinate Inflorescence Types Creation of a Twice-Compound Rhipidium from an Alternating Phylotaxy Higher-order compound inflorescences from development of axis on alternating sides of the primary axis 0 0 0 1 2 This looks like a panicle of a grass

18 Determinant (?) Inflorescences: Cyme: composed of usually numerous 3-flowered units Cymes can be of many different shapes due to differences in branching pattern Cyme: cabbage sprout A simpler view of Cymes (Mostly All Wrong) These are secondary inflorescences A determinate Umbel Dichasium Compound Dichasium Rhipidiums

19 Secondary Inflorescence Types MIU is of a Type different than that of the shoot Rhipidiums arranged as a Corymb (often confused with a Compound Corymb) Panicle Rhipidiums arranged as a Raceme (often confused with a Compound Raceme) Lower flowers usually develop first, but sequence may be reversed

20 Spikes arranged as a Raceme Unbranchable; differentiates this from the earlier Compound Spike Secondary Inflorescence Types MIU is of a Type different than that of the shoot Verticillaster Verticils arranged as a Spike Catkin/Ament Compound Dichasiums arranged as a Spike Heads arranged as a determinate Compound Corymb or Panicle Spikelets arranged as a Panicle (Rhipidiums arranged as a Raceme) Thyrse Compound Dichasiums arranged as a Raceme Lower flowers usually develop first, but sequence may be reversed

21 Raceme: Flowers, with pedicels, arranged on a long axis = rachis. Defined by most as indeterminate in both senses. Unbranched, so it is a florescence. Compound Raceme, called by some a Panicle: Different than the first Compound Raceme, the 2 o are not branchable. An alternative definition of a Panicle: know it but dont use it Walters and Keil

22 Dichasium Potentilla recta Linnaeus MIU is a dichasium, arranged in compound dichasia, which are arranged in a determinate spike/raceme Compound Dichasium (showing only one lateral) Spike

23 Compound and Multiple-compound Rhipidium


Download ppt "The most important thing to remember when using this (or any other) glossary is that just because some aspect of an organism is dignified by a sesquipedalian."

Similar presentations


Ads by Google