AGRO211 Theory Flashcards
What are the most important grains?
Wheat, Rice, Maize, barley, oats, sorghum, rye, millets.
What inflorescence type is this?
Primary axis with racemes or spikes
Which grain is a staple in the tropics and subtropics?
Rice
What inflorescence type is this?
Raceme
What growth form of grass is shown?
Cane forming
Bamboos
Woody stems
What feature of the inflorescence is located at A?
Flag leaf
What is Apomixis?
Asexual reproduction which produces a seed without the fusion of a sperm and egg.
What inflorescence type is this?
Subdigitate
What is the advantage of asexual reproduction?
It conserves well adapted genotypes, because offspring are identical to parents.
What is an aggregate fruit?
One that is derived from many ovaries from a single flower.
What feature of the inflorescence is located at A?
Spikelets
What inflorescence type is this?
Spike
What is a dry indehiscent fruit?
Fruit what does not open at maturity.
What grass growth form is shown?
Mat
Horizontal stems with long internodes above ground (Stolons)
Horizontal stems with short internodes below ground (Rhizomes)
Cereal grains supply ___% of the world’s food for human consumption?
60%
What inflorescence type is this?
Spatheate
What is a fruit?
The unit that stores the seed.
What is the culm of a grass plant?
The flowering stem off which the inflorescence grow.
What inflorescence type is this?
Digitate
What are the defining factors of a Eudicot?
Flower parts usually in fours or fives
Leaves usually have netted veins (reticulate)
Secondary growth common (up and out), arises from vascular cambium.
vascular bundles distributed as a ring
Ususally a taproot system
Seeds have two cotyledons
Which family is the only family larger than poaceae?
Asteraceae
What are the defining factors of a monocot?
Flower parts in threes
Leaves usually with paralell veins
Usually no secondary growth
Vascular bundles distributed in ground tissue in stem
Fibrous root system
Seeds have one cotyledon
What is the leafy shoot of a grass plant called?
A tiller
Grasslands comprise roughly ___% of the worlds vegitation
20%
Perennial grasses feature two horizontal stem types. What is this stem called if growing below ground?
Rhizomes
What inflorescence type is this?
Open Panicle
What are the two methods of asexual reproduction that grasses use?
Vegitative cloning
Apomixis
What family are the graasses in?
Poaceae
What parts make up a tiller?
Roots, Stem and leaves
What is a simple fruit?
One seed to each fruit
When are grasses most susceptible to overgrazing?
During their reproductive phase, as they push their growth buds above ground to produce an inflorescence rather than leaf material.
What inflorescence type is this?
Spatheate
What feature of the inflorescence is located at A?
Rachis
What growth form of grass is shown?
Tufted
Upright growth
Cluster of roots around base
What are the 4 basic grass growth habits?
Tufted, Mat, Cane, and hummock
What feature of the inflorescence is located at A?
Pedicel
Which grain is a staple of the temperate regions?
Wheat
How many genera and species of Poaceae are there?
650 Genera
12,500 Species
What growth form of grass is shown?
Hummock-forming
Mound, doughnut forming
Base woody
Unlike tufts, many tillers grow very close together
Perennial grasses feature two horizontal stem types. What is this stem called if growing above ground?
Stolons
Where is the crown of grass, and why is this advantageous during grazing?
Close to the soil surface
Buds remain protected, so the plant can continue to grow once grazing removes plant material.
What feature of the inflorescence is located at A?
Peduncle
What us a multiple fruit?
A fruit derived from many ovaries of many flowers clustered together on an inflorescence.
What is a prostrate growth habit?
Growing horizontally and flat across the soil surface
What is a dry dehiscent fruit?
A fruit which opens at maturity
What inflorescence type is this?
Contracted Panicle
