Structure and Morphology
This presentation is about grasses, their structure
and morphology generaly, explaining the most
importants parts of them, to demostrate the
importance they have in our planet and in our
INDEX 1- Introduction
2- Phases of the development
IV. Seedling development
V. Germination and emergence
VI. Development of the root sistem
XII. Inflorescence and florets
• Grasses are grouped in about 650 Characteristics:
to 750 kinds of plants, which -The grass family has the best range of
include 10.000 species. adaptation to temperature and
• Grasses are the dominant
vegetation on much of the world´s -Almost all are herbaceous.
-All the cereal crops and
-They vary widely in structure and
about 75% of the species
used as forages are grasses.
→ By photosynthesis pathway,
boot , C3 and C4
- The grass family has the most species
with the C4, which is characteristic of
-The C3 pathway is characteristic of
→ By their life cycle:
• Shallow planting is critical to
– emerge and develop
quickly before the
reserves are used up
when growth starts
• Seedling development is a
critical factor in forages
- an adequate stand of plants needs to
be established to be productive.
Similar for all grasses.
GERMINATION AND EMERGENCE
1st root system
-Sign of germination --> emergence of the radical (primary root).
-In seedling development up to five seminal roots may emerge
–very important early on for water uptake and nutrient absorption.
-The epicotyl elongates to emerge from the seed and agreement
toward the soil surface.
-This root system is short-lived
2nd root system
→ Next, the mesocotyl ( between scutellar and
coloptilar nodes) also elongates.
-In warm-season grasses very close to the soil surface.
DEVELOPMENT OF THE ROOT
→ The adventitious roots grow downward rapidly to provide water and
minerals for the plant
• the seedling is considered established.
→ The improved water status facilitates adventitious rot development.
→ Adventitious roots rarely grow into dry soil.
-Growing plant development
modifications that allow each
species to be adapted to specific
-This is obtained by several structures:
• Leaves are borne on the stems.
• Each leaf consists of a sheath, blade, ligule, and in some cases
• The sheath is green and photosynthetic.
• Nonreproductive or vegetative tillers
tend to be very short, consisting of
node and unelongated internodes.
• When there is a flowering stimulus,
(daylenght or temperature), the soot
apex develops into the reproductive
• Also there can be stoloniferus stems.
They originate from auxiliary buds
near soil level.
• Grasses have an adventitious fibrous root system.
• New tiller develops adventitious roots from lower
• Each tiller begins like a new seedling.
• The root system of grasses develops especially in the
upper soil horizons,
– though it depends on the species.
• A lot of species differs in distribution of roots in the
INFLORESCENCE AND FLORETS
• Consists of a group or cluster of spikelets, •The flowers are usually small and
the basic reproductive unit. perfect, have a functional pistil and
•Many forage grasses are cross-
pollinated by the wind.
Many grasses flower only once a year because they require:
a specific sequence of a short photoperiod, a cold period
and a long day for the shoot apexes to be differentiated and
develop into the inflorescence.
• We can say that plants consist of roots, stems, leaves and most
have flowers and fruits at certain times of year.
• The most important aspects of the plants are studied.
● morphology, structure and aspects related to their survival
mechanisms such as the flowering or the seedling development
In our opinion this article is very interesting because the text
refers to basic aspects of grasses.
We also believe that society should know a minimum about
plants, since these are the basic human food grains.
− For example: the cereals.
Finally to say that without the existence of plant, the life on
this planet would be impossible.