Week
6 Laboratory
Caryophyllids
This lab will cover the Caryophyllids
– the first of the three major groups of core eudicots. This group contains
only the order Caryophyllales, but the order contains a diversity of plants
ranging from carnivores like the sundew family, stem-succulent, desert specialists
like the cactus family, salt loving halophytes like the amaranth family, to
temperate leaf-succulents like the spring beauty family. Besides the obvious
adaptations to xeric conditions, salt, and low nutrients, the majority of
families lack petals or have petals derived from stamens. The laboratory is
designed so that you become familiar with this order by dissecting flowers
of representative members, observing demonstration materials of other members,
and by learning to identify local genera (and knowing genus, family, and common
name). Two species are also provided for practice in using a genus key from
the Manual of Vascular Plants of Northeastern United States (Gleason &
Cronquist).
Refer to pp. 238-249 in Plant Systematics
and pp.54-69 in Zomlefer resource for information on this group of angiosperms.
Also, please visit the University of Wisconsin Plant
Systematics Collection homepage that will describe these and other
families in some detail and are linked to images.
I. Detailed floral dissections on
frozen/pickled flowers. Include these in your laboratory notebook with
illustrations and labeled parts. Refer to Gleason & Cronquist [GC] for
descriptions of the species as needed, and toPlant Systematics [T]
or Zomlefer [Z] for descriptions and drawings of the families.
1. Phytolacca
americana (Phytolaccaceae
- pokeweed, pokeberry) (pp. 239 [T], 61-63 [Z], 92 [GC])
Phytolacca
has a very simple type of inflorescence, what kind is it?
The gynoecium is modified from the
more typical placentation type seen in the subclass; what placentation
does it exhibit? How many carpels are there? How many ovules in each?
What kind of fruit is produced?
Take a look at the demonstration
jar of another species of Phytolacca discovered in Olin Park. Compare
the type of gynoecium; what is different about this species?
Give a floral formula for Phytolacca.
2. Saponaria
officinalis (Caryophyllaceae
- soapwort, bouncing-bet) (pp. 244-249 [T], 54-56 [Z]; 126 [GC])
Notice the inflorescence of Saponaria.
It is typical for the family. What kind is it?
The calyx and/or corolla show some
modifications; can you list them? Find the blade and claw of the corolla.
Saponaria possesses the
typical placentation type of the group, what is it? What kind of fruit
is produced?
Provide a floral formula for Saponaria.
II. Demonstration floral dissections.
Look at these in as much detail as you want, but be sure to identify and understand
the characters indicated on the sheet next to each floral dissection. Many
of these also will be found in Plant Systematics [T], Zomlefer [Z],
and Gleason & Cronquist [GC].
1. Portulaca
oleracea (Portulacaceae
- purslane) (pp. 56-58 [Z], 110 [GC])
2. Chenopodium
album (Chenopodiaceae
- lamb's quarters) (pp. 241-244 [T] - placed under Amaranthaceae, 65-67
[Z], 96 [GC])
3. Amaranthus
retroflexus (Amaranthaceae
- pigweed) (pp. 241-244 [T], 67-69 [Z], 104 [GC])
4. Polygonum
pensylvanicum (Polygonaceae
- smartweed) (pp. 249 [T], 86-87 [Z], 132 [GC])
III. 11 genera of Wisconsin plants
to be able to identify on site (* = not presently found in Wisconsin).
Herbarium specimens of these plants
will be marked to genus (and to family) and will be kept in the laboratory
until the next laboratory exam when you will be tested on them. Use copies
of Gleason & Cronquist as much as possible to understand why each genus
is different from other genera in the same family. This will help you not
only to identify the plants to genus and family, but might be necessary as
we will test you with different herbarium sheets of these plants!
1. Froelichia
(Amaranthaceae
- cottonseed)
2. Amaranthus
(Amaranthaceae - pigweed)
3. Opuntia
(Cactaceae
- prickly pear)
4. Phytolacca
(Phytolaccaceae
- pokeweed)
5. Chenopodium
(Chenopodiaceae
[now Amaranthaceae] - lamb's quarters)
6. Saponaria
(Caryophyllaceae
- bouncing bet, soapwort)
7. Silene (Caryophyllaceae
- catchfly, campion)
8. Arenaria (Caryophyllaceae
- sandwort)
9. Portulaca (Portulacaceae
- purslane)
10. Claytonia
(Portulacaceae - spring beauty)
11. Polygonum
(Polygonaceae
- smartweed, knotweed)
IV. Additional representatives
of these and other families are placed around the room. As time permits, examine
these plants and especially note the floral structures. You will not be required
to know these plants; they are simply provided to illustrate additional members
of these families.
1. Rivinia humilis (Phytolaccaceae
- rouge plant)
2. Talinum paniculatum (Portulacaceae
- jewels of opar)
3. Portulaca grandiflora (Portulacaceae
- rose moss)
4. Gypsophila elegans (Caryophyllaceae
- baby's breath)
5. Dianthus chinensis (Caryophyllaceae
- rainbow pink)
6. Dianthus barbatus (Caryophyllaceae
- sweet William)
7. Mirabilis nyctagineus (Nyctaginaceae
- wild four-o'clock)
8. Bouganvillea glabra (Nyctaginaceae
- bouganvillea)
9. Pisonia umbellifera (Nyctaginaceae
- para para)
10. Cactaceae
spp. (cacti) - look for examples of the three subfamilies
11. Didiereaceae
- cacti mimics from Madagascar (octopus plant and others)
12. Lithops (Aizoaceae
-- living stones)
13. Kochia scoparius (Chenopodiaceae
[ow Amaranthaceae] - summer cypress)
14. Gomphrena globosa (Amaranthaceae
- globe amaranth)
15. Celosia cristata (Amaranthaceae - feather amaranth, cockscomb)
16. Amaranthus caudatus (Amaranthaceae
- loves lies bleeding)
17. Nepenthes (Nepenthaceae
- pitcher plants)
18. Drosera (Droseraceae
- sundews)
19. Dionaea (Droseraceae -
Venus flytrap)
20. Fagophyrum esculentum (Polygonaceae
- buckwheat)
V. Key these two plant specimens
to species using the Gleason & Cronquist provided. This kind of question
might well be on a laboratory exam.
1. Arenaria sp. (p. 114 [GC])
2. Polygonum sp. (p. 132 [GC])
[this species is low growing, found in a lawn]
