Plants and People

1
Plants and People

• Major Families II
• Grains and Legumes

2
Why grains and legumes? And why together?
3
Grain legume complete protein
That peanut butter sandwich is looking pretty
good now, isnt it?
4
Poaceae - The Grass Family

• Humans devote more than 70 of the Earths
  farmlands
• to the production of cereal grains
• Grasses provide at least 50 of the worlds
  caloric
• intake
• Some anthropologists are of the opinion that
  the use of
• cereal grain was a prerequisite for the
  formation of a civilization

5
Vegetative Characteristics
6
Grass Inflorescence
The spikelet is the basic unit of grass
inflorescence, with one or more florets making up
the spikelet. The spikelet is subtended by two
sterile bracts known as glumes. The glumes
define the spikelet they and everything above
them make up the spikelet.
Spikelet
7
Floral Morphology
Flowers of the grass family are highly reduced
and non-showy and are described using unique
terminology.

• The perianth has been reduced to structures
  colled lodicules, located at the base of the
  ovary (these may be absent)
• The mature ovary (fruit) is termed a grain or
  caryopsis
• Each flower is enclosed by two fertile bracts,
  with the larger, lower bract, the lemma enclosing
  the usually smaller, upper bract termed the palea
• The tip of a glume, lemma or palea may be
  extended into a bristle-like structure called an
  awn
• The lemma, palea and the flower make up the
  floret

8
Floral Morphology
An oat spikelet
palea 1
palea 2
awn 1
stigma
anthers
lemma 1
lemma 2
awn 2
glumes
9
The Beans
Fabaceae/ Papilionoideae/ Faboideae
Caesalpiniaceae/ Caesalpinoideae
Mimosaceae/ Mimosoideae
Legumes
10
The Bean Families

• Everyone agrees that the legumes form a
  coherent whole based on the presence of a single
  carpel that matures into a legume.
• They can be divided into three groups based on
  the arrangement and structure of the androecium
  and perianth, collectively called the
  androperianth.
• The question is whether to
• --treat them all as a single family Fabaceae
  (broad sense) with
• three subfamilies
• or
• --treat them as separate families in the order
  Fabales.

11
Fabaceae (strict sense), Papilionoideae/Faboideae
Flowers in Fabaceae are zygomorphic and
papilionaceous (butterfly-like). The corolla is
consists of 5 petals a banner, 2 wings, and a
fused keel. The banner is exterior to the
wings.
12
The fused keel encloses the unique androecium, 10
stamens in 9 fused 1 free arrangement (this is
termed diadelphous.) The stamens surround the
style but are not fused to it.
13
Caesalpiniaceae/ Caesalpinioideae
Flowers in the Caesalpiniaceae Family are
zygomorphic and papilionaceous (butterfly-like).
The corolla is consists of 5 petals a banner, 2
wings, and 2 un-united keel petals. There are 10
stamens that are free and often unalike. The
banner is usually located interior to the wings.
banner
wings
keel petals (not fused)
14
Mimosaceae/Mimosoideae
Flowers in the Mimosaceae are actinomorphic.
Many tiny flowers, each with long, showy stamens,
are grouped into globose or elongated
inflorescences. These stamens are the showy part
of the flower, rather than petals. The corolla
is either free or fused.
stamens
corolla
calyx
an individual flower
15
Pseudocereals
A pseudocereal is a plant that produces a
grain-like fruit That is not a true caryopsis.
Often, these plants are grown in areas that are
too cold, too dry, or too high to grow cereals
successfully.
16
Quinoa
Chenopodium quinoaChenopodiaceae Native to the
Andes of South America. Cultivated since about
3,000 B.C. Tolerates high altitude, cold,
drought. Does well in parts of North America.
17
Amaranth
Various species of Amaranthus--Amaranthaceae. Nat
ive to the Americas. Was a staple of the Aztecs.
Cultivated since ca. 6,000 BC. High in lysine.
18
Buckwheat
Fagopyrum esculentum Polygonaceae Native to
Southeast Asia. Domesticated around 6,000 B.C.
19
Lab Today

• Make sure to examine the oat spikelet dissected
  for you under one of the microscopes and the
  vegetative parts of a grass.
• Sketch your own diagram of the oat spikelet,
  labeling the important terms, and make sure you
  understand the different parts of the spiklet!
• Compare the sample legume material with
  information given to you in lecture, paying close
  attention to the arrangement and structure of the
  androecium and perianth.
• Examine the grains, legumes, and
  pseudo-cereals, filling out the table provided
  for todays lab

20
(No Transcript)
21
(No Transcript)