Lab 2: Cereal Crops Flashcards
Bread wheat Latin name
Triticum aestivum
Triticum aestivum common name
Bread wheat
Triticum aestivum inflorescence
Spike
Spike
Inflorescence where spikelets are attached sessile to rachis
Arrangement of spikelets along the rachis
Arranged distichously along rachis
Rachis node
The point of attachment of a spikelet to the rachis
Wheat spikelet
-two glumes enclosing max five florets
Rachilla
Small rachis of the spikelet that the florets attach to in an alternate manner
Which florets in a wheat spikelet usually set seed?
-bottom two
-next two depending on growing conditions
-fifth always always sterile
Which kernels in wheat are the largest?
-primary and secondary largest
-size decreases in order
In a particularly poor growing year, how many florets would a wheat spikelet usually contain?
Probably less than five
Beard
Extended awn from the lemma
Winter wheat latin name
Triticum aestivum
Triticum aestivum common name
Winter wheat
How many florets does a Triticum aestivum spikelet contain?
Maximum six
What does Triticum aestivum require to develop a head?
Vernalization
Vernalization
Exposure to prolonged periods of chilling temperatures
Durum Wheat latin name
Triticum durum
Triticum durum common name
Durum wheat
Triticum durum inflorescence
-essentially the same as any bearded bread wheat
-lemma always extended into a beard
Lemma
The lowermost of the two bracts on the outside of a floret
-an awn extended into a point
Lemma types
- Beardless
- Tip or apical awn
- Bearded
Beardless wheat
No lemma awn present
Tip or apical awn wheat
The lemma tip is extended to a thin point or short awn
Bearded wheat
The lemma tip is extended to a long and conspicuous awn
Stem solidness of wheat
-most varieties have a hollow stem in internode sections on the culm
Characteristic of wheat varieties bred for sawfly resistance
Culms filled with pith (solid stem)
Barley latin name
Hordeum vulgare
Hordeum vulgare common name
Barley
Barley inflorescence type
Spike
How many spikelets per rachis node in Hordeum vulgare?
Three spikelets per rachis node
Hordeum vulgare # florets per spikelet
Single floret per spikelet
What structures enclose the floret of a Hordeum vulgare spikelet?
A pair of small, narrow glumes with awns on their tips
Characteristic of lemma and palea in Hordeum vulgare
Lemma and palea remain tightly attached to mature grain —> forming the hull
What structures for the hull in the grain of Hordeum vulgare?
Lemma and palea
How many florets in a six-row barley spike are fertile?
Each of single florets in the three spikelet attached per rachis node is fertile
What does a fertile floret of a spike inflorescence produce?
A grain
Which spikelets in two-row barley are fertile?
Only the central spikelet bears a fertile floret (two lateral spikelets bear an infertile floret)
What is responsible for the transformation from two-row barley to six-row barley?
The mutation of one gene
Six-row barley vs. Two-row barley
Six-row: three fertile florets per rachis node; three spikelets per rachis node
Two-row: one fertile floret per rachis node; three spikelets per rachis node
What is the most useful and accurate way to differentiate between barley varieties?
Spike characteristics
Types of lemma awns in barley?
- Awned
- Bearded
- Hooded
Bearded barley
Have a long coarse awn forming a beard extending from tip of lemma
Hooded barley
Top of lemma develops into a three forked structure covering part of kernel
(Trident)
Lemma awn textures in barley
- Smooth
- Semi-rough
- Rough
Smooth lemma awn texture
No barbs
Semi-rough lemma awn texture
Barbs present on part of the awn
Rough lemma awn texture
Barbs present on the entire awn
Do 2-row and/or 6-row barley varieties have uniform seed size?
2-row: uniform
6-row: varies
What structure compose hull of barley
-almost all varieties have a tightly attached hull composed of lemma and palea
Are almost all barley varieties hulled or hulless?
Hulled
Characteristic of free threshing barley varieties
Lemma and palea come off nearly all kernels during threshing
Rye latin name
Secale cereale
Secale cereale common name
Rye
Secale cereale inflorescence type
Spike
How many spikelets per rachis node in Secale cereale?
One spikelet per rachis node (similar to wheat)
How many florets does a Secale cereale spikelet consist of?
Three
What structure encloses the florets of a Secale cereale spikelet?
A pair of short narrow glumes
Characteristics of lower two florets of a Secale cereale spikelet
Equal in size and fertile
Characteristics of the third floret of a Secale cereale spikelet
-usually sterile
-found at tip of a small rachilla between the two fertile florets
Characteristics of lemma of Secale cereale
Lemma extended into a beard, which is always barbed
Characteristics of Secale cereale grains
-free threshing
-long and slender
-various shade of blue-green, yellow, or brown
Secale cereale is the only cereal commonly grown in Canada that requires…
Cross-pollination
How does cross-pollination occur in Secale cereale?
-lemma and palea open at anthesis —> expose ovary
What problem is rye exposed to during the cross-pollination process?
Open nature of lemma and palea make rye the cereal most susceptible to ergot
Oat latin name
Avena sativa
Avena sativa common name
Oat
Avena sativa inflorescence type
Panicle
Pedicels
Secondary branches (off of central rachis) to which the spikelets attach to in panicle inflorescence
Panicle in common and hull-less oats
Made up of branches occurring at the rachis nodes, each bearing several single spikelets on pedicels
Arrangement of pedicels in inflorescence of Avena sativa
Alternate form side to side on the rachis
Distinguishing characteristic of “side oats”
Branches are all on one side of the rachis
Characteristics of glumes in Avena sativa
-each spikelet consists of a large pair of papery glumes
-slightly unequal in size
-do not have awns
-enclose florets
How many florets per spikelet in Avena sativa? How are they arranged?
Three florets attached on alternate sides of the rachilla
If present, where do awns arise from in Avena sativa? What are these awns called?
-arise from mid-back of lemma
-called dorsal lemma awns
Size of florets within Avena sativa spikelet?
-vary
-first=largest —> largest grain
-second =about half size
-third =usually very small (only sets a small grain in a few varieties)
Wild oats latin name
Avena fatua
Avena fatua common name
Wild oats
Characteristics of Avena fatua
-usually taller than tame oats
Kernels:
-slender
-variable coloured
-hairy
-“sucker mouth” —> scar of attachment
Dorsal Lemma awn:
-each kernel has
-spirally 90* twisted (assists in movement into soil profile)
-sensitive to changes in light and humidity
Dormancy:
-wide range of dormancy conditions (even between kernels from same inflorescence)
What is the resulting kernel of a rare cross between a wild and tame oat called?
Fatuoid
Triticale latin name
X Triticosecale Wittmark
X Triticosecale Wittmark common name
Triticale
X Triticosecale Wittmark is the result of a successful cross between…
Triticum sp. and Secale sp.
Wheat and rye
Morphologically, triticale resembles which of its parent species more?
Wheat
X Triticosecale Wittmark inflorescence type
Spike
How many spikelets and florets per rachis node in a X Triticosecale Wittmark spike?
Five spikelets per rachis node
Five florets per spikelet
Distinguishing characteristics of triticale heads/spikes
-Maturing heads are pendulous
-spikes and kernels often larger than spike of wheat or rye
-pubescent below lowest spikelets on the head
Triticale kernels are always…
Free threshing
X Triticosecale Wittmark growth habit
Spring or winter
X Triticosecale Wittmark end-use
Grain or forage (depending on cultivar)
-feed grain: relatively high protein levels
-grown primarily as an alternate feed crop on prairies
-whole grain and flour used in cracker and other speciality food products
-sterile triticale hybrids use in soil restoration projects
Triticale vs Wheat
Triticale:
-pendulous maturing heads
-larger spikes and kernels
-pubescent below lowest spikelets on the head
-increased vigour
-always free threshing
-high levels of protein
Canaryseed latin name
Phalaris canariensis
Phalaris canariensis common name
Canaryseed
Saskatchewan is the leading producer and exporter of what cereal crop?
Canaryseed
Phalaris canariensis end-use
-almost exclusively for feed mixtures for caged and wild birds
What are the two types of canaryseed?
- Itchy
- Hairless
Most of the Phalaris canariensis grown in SK is what type?
Itchy
Distinguishing characteristic of itchy canaryseed?
Seeds have tiny sharp hairs on their base
Why is canaryseed less heat and drought tolerant than wheat?
It is a shallow rooted crop
Phalaris canariensis inflorescence type
Spike-like panicle
Why should canaryseed never be grown on flax stubble?
Its seeds sometimes get confused with flax
Canaryseed seeds vs flax seeds?
Canaryseed:
-way smaller than flax
-different colour
