Rice

1. Lecture 4 List of cultivated crops, economic
parts, chromosome number and family
description of Poaceae; Key botanical features
of Rice and Wheat
PBG 101 Introduction to Agricultural Botany (1+1)
PBG 101 Course Teacher
Dr. R.Kalaiyarasi
Professor(PBG)
Department of Genetics and Plant Breeding
Tamilnadu Agricultural University, Coimbatore-641 003
Mobile : 9443440881
Email : kalaiyarasi_2002@yahoo.com
Facebook : Kalaiyarasi Ramachandran

2. Family characters of Poaceae
• Distribution: Most of the members of the family are
cosmopolitan in distribution.
• The plants are commonly found in temperate regions and
are also found in tropical and sub-tropical
regions.
Habit: annual or perennial herbs, rarely woody, mostly
wild, some are cultivated.
Root: adventitious, fibrous.

3. Family characters of Poaceae
• Stem: erect, prostrate or creeping, commonly fistular,
often solid, presence of distinct nodes and
internodes, the stem is called culm.
• Leaf: alternate, exstipulate, sessile, simple and
sheathing base covering the inter node.
Leaf blade linear to lanceolate, parallel venation.

4. Family characters of Poaceae
• Floral characters:
Inflorescence: racemose type, spiklet.
Flowers: bracteates, sessile, zygomorphic, bisexual or
unisexual, incomplete and hypogynous.
Perianth: absence or mostly represented by two
membranous lodicules as in rice, wheat; 3 in
bamboo and one in Malice spp.

5. Family characters of Poaceae
• Androecium: stamens 3 or 3+3 , rarely reduced to 2 or 1, distinct,
filaments slender and long, anther dithecous, versatile and dehisce
by longitudinal slits.
• Gynoecium : carpels 1,2 or 3, syncarpous, ovary rounded, superior,
unilocular with a single basal ovule, style and stigma feathery.
Fruit: caryopsis
Floral formula: Br.% ○ P2 (lodicules) or absent
A3 or 3+3 G (3) or (2) or 1

6. List of Cultivated crops in Poaceae
Common
Name
Botanical Name Common name Botanical name
Rice Oryza sativa L Sugarcane Saccharum
officinarum
Wheat Triticum aestivum Napier grass Pennisetum
purpureum
Maize Zea Mays Guinea grass Panicum maximum
Sorghum Sorghum bicolor Kolukattai Grass Cenchrus sp.
Cumbu Pennisetum glaucum White kolukkattai grass Cenchrus ciliaris
Ragi Eleucine coracana Neela kolukattai grass Cenchrus glaucus
Samai Panicum sumatrance Black kolukattai grass Cenchrus setigerus
Tenai Setaria italica
varagu Paspalum scrobiculatum
panivaragu Panicaum miliaceum
kudiraivali Echinochloa frumentosa

7. Rice
Scientific name : Oryza sativa L.
Chromosome No : 2n = 24
Common Names
» Arisi
» Nellu
» Chawal

8. Systematic position
Division : Phanerogams
Sub-Division : Angiosperms
Class : Monocotyledon
Series : Glumaceae
Sub class : Glumiflorae
Family : Poaceae
Sub family : Poacideae
Tribe : Oryzae
Genus : Oryza

9. Origin:
Place of origin : South and South east asia
Distribution : China, India, Bangladesh, Japan,
Pakistan, Burma, Thailand and
Vietnam.
In India : All the states.

10. Two forms of cultivated rice
Asian rice – O. sativa
African rice – O. glaberrima
Origin of Cultivated Rice
1. Polyphyletic origin
2. Monophyletic origin

12. Monophyletic
Both Asian rice and African rice originated from a
common parent. (O. perennis)
Most accepted one - both Asian rice and African rice
are similar in most characters
Except
• Glume pubescence
• Ligule size
• Kernel colour

13. Species of the genus Oryza
Botanical name Chromosome No. Genome Origin
O. sativa 24 AA Asia
O. nivara 24 AA Asia
O. meridionalis 24 - Australia
O. longistaminata 24 AA Africa
O. rufipogan* 24 AA Asia
O. glumaepatula 24 - America
O. grandiglumis 48 CCDD America
O. glaberrima 24 AA Africa
O. barthii 24 AA Africa
O. australiensis 24 EE Australia
O. latifolia 48 CCDD America
O. alata 48 CCDD America
* Source of CMS

14. Species
Botanical name Chromosome
No.
Genome Origin
O. eichingeri 24, 48 CC, BBCC Africa
O. minuta+ 48 BBCC Asia
O. punctata 48 BBCC Asia
O. officinalis 24 CC Asia
O. granulata 24 - Asia
O. meyeriana 24 - Asia
O. ridleyi 48 - Asian
O. longiglumis 48 - New Guinea
O. brachyantha 24 FF Africa
O. schlechteri - - New Guinea
+ Multiple resistant sp.

15. Subspecies of cultivated Oryza sativa
Rice is adapted to diverse climatic conditions and soils.
This resulted in the evolution of three geographical races
which has given subspecies status.
The three subspecies of Oryza sativa
1. O. sativa subsp indica
2. O. sativa subsp japonica
3. O. sativa subsp javanica

16. Characters Indica Japonica Javanica
Size & colour
of leaves
Broad to narrow
light green leaves
Narrow dark
green leaves.
Broad, stiff light
green leaves.
Grain type Long to short,
slender, flat grains
Short,
roundish
grains.
Long, broad,
thick grains.
Tillering Profuse tillering Medium
tillering
Low tillering.
Plant stature Tall to
intermediate plant
stature
Short to
intermediate
plant stature
Tall
Differences between subspecies
Contd.

17. Characters Indica Japonica Javanica
Awn Awnless Awnless to long
awned
Long
awned
Grain shattering Easy shattering Low Low
Types of tissue Soft plant tissue Hard Hard
Photosensitivity Varying
sensitivity to
photoperiod
very low Low
Amylose content 23-30% amylose 10-24% 20-25%
GT Variable GT Low GT Low GT

18. Family : Poaceae. (Graminae)
Habitat
Tropical and subtropical
Habit
• Semiaquatic
• Free tillering
• Annual herbaceous species
• Fibrous root system.
BOTANY OF RICE

19. • The jointed stem of rice
called Culm
• Made up of a series of
nodes and internodes.
• Erect, cylindrical, hollow
at the internodes and
solid at the Nodes
• Internodes - shorter at the
base and progressively
longer at top.
Stem

20. • Leaves- alternate on the stem in two ranks one at each
node.
• The leaf sheath is continuous with the blade.
• There may be swelling at the base called pulvinous.
• Uppermost leaf below the panicle is called the flag leaf.
• Ligule is a small, white, triangular scale that looks like a
continuation of the sheath.
LEAVES

21. • At the base of the blade, i.e. around the junction between
the blade and sheath, there is white band called the
collar.
• A pair of hairy and sickle shaped auricles are located at
the junction between the collar and the sheath.
• Leaf sheath encircles the whole or part of the internode.
• Leaf blade long narrow pubescent having spiny hairs on
the margins.
LEAVES

22. • Loose terminal panicle.
• Usually 10-30 cm long.
• Erect or drooping,
• Base of the peduncle
• Enclosed in the flag leaf sheath
Inflorescence

23. • Spikelets occur in single, attached to
secondary rachis.
• Spikelets are laterally compressed, borne
on a short pedicel and is subtended by two
miniature sterile glumes that are lanceolate
in shape.
• Lemma is tough, large, boat shaped,
strongly five nerved, apex is solid or it may
be awned.
• Palea is narrower than lemma and strongly
three nerved.
• The extended tips of the lemma & palea
are the “apiculous”.
Spikelet structure

24. Perianth is modified and restricted into small fleshy
transparent portions called lodicules.
• At anthesis, the lodicules become turgid and thrust
open the lemma and palea apart exposing the fertile
stamens.
• Stamens are six in number in two rows,
• Filaments are slender, Anthers versatile,
• Pistil with single ovule,Two plumose stigma.
Spikelet structure

25. Rice Floral diagram
• Floral formula: Br.% , P2 (lodicules) A3+3 G 1

26. Grain structure
Economic part : The seed of the paddy
is called “Caryopsis”
The ovule after fertilisation develops into seed
with seed coats (outer layer) completely fused
together
with the developing ovary wall or pericarp.

28. • The pericarp is made up of distinct
layers of quadrangular cells which
form the epicarp.
• These cells have slight thickening
and are followed by cells which are
much compressed and form the
mesocarp consisting of two to three
layers.
• The endocarp is a single layer of tube
cells.
1. THE PERICARP OR
FRUIT COAT
Epicarp
Mesopcarp
Endocarp

29. 2.The Seed Coat
• A few layers of cells
below the pericarp are
the integuments of seed
coats.

30. 3.The Aleurone layer
A prominent layer of
rectangular cells
which contain
protein lying next to
the seed coats.

31. The CARYOPSIS that comes from the field directly is
known as paddy or.
Rough rice - 20% hull (Ummi) i.e. lemma and palea.
The process of removing the hull - hulling.
This can be done by hand pounding or by dehusker.
ROUGH RICE
rough rice

32. After hulling the produce is known as ‘brown rice’.
Then next step is polishing.
The brown rice consists of pericarp, nucellus, aleurone
layer and embryo.
All these are collectively known as bran, which is rich in
oil (15 to 20%), protein, mineral salts and vitamins.
During polishing process most of
the nutrients are lost.
BROWN RICE OR HUSKED RICE
brown rice

34. Economic Importance
• Whole grain is cooked and eaten.
• Rice grain - producing parched rice, popped rice / beaten
rice
• Rice flour - for preparation of edible items and ice cream
• Rice Starch - in textile industry, manufacture of dextrin /
glucose.
• Rice bran - valuable livestock and poultry feed
• Rice bran oil - for making soaps and cosmetic
• Rice straw - for cattle feeding, making straw boards, paper/
mats.

35. Value added products and their uses
Rice bran
• It’s colour and nutty flavour is an excellent source of
thiamin, niacin, vitamin B-6, iron, phosphorus,
magnesium, potassium & fiber.
• Rice bran - used to feed livestock.
Rice hull
Hulls are used as fuel in power plants and rice mills

36. Rice bran oil
• It is a high quality cooking oil
• Effective in reducing cholesterol in the blood.
• Used for making soaps and cosmetics

37. Brewers rice
• Used in brewing beer and other fermented products.
• Rice vine, with 10-15 per cent alcohol - from glutinous rice

38. Rice Flour
• To produce rice pasta, chips / snacks / breakfast cereals.
• Substitute for wheat flour to persons who are allergic
Broken Kernels
Used to make various products including rice flour
and pet food

39. Rice and Green revolution
• Green revolution in rice was started after the discovery
of dwarf mutant Dee-Gee- Woo – Gen by a farmer in
Taiwan.
• Utilizing this in Taiwan developed first dwarf variety
T(N) 1.
• Later of this Dee Gee Woo Gen Was utilized in IRRI
and released Wonder Rice, IR 8 . (Peta x Dee-Gee -
Woo -Gen.)

40. Dr R.Kalaiyarasi
Visit to IRRI, Manila ,
Philippines and
Participated in
International Rice
Research Conference.
Discussion with Father
of Hybrid Rice -
Dr.Yuan Long Ping
Father of hybrid rice
Dr. Yuan Long Ping
Dr.R.Kalaiyarasi
Dr.R.K

41. Dr.R.Kalaiyarasi Visit to IRRI, Manila,
Philippines and Participated in IRRC.
Father of Hybrid Rice Dr.Yuan Long Ping
Yuan
Long
Ping
R.Kalaiyarasi