RICE PRODUCTION TECHNOLOGIES

PRESENTATION FOR THE TRAINEES OF TRAVELLING SEMINAR JOINTLY ARRANGED BY PAKISTAN AND CHINA 2017

1. RICE CULTIVATION
TECHNOLOGY AND
DIFFERENT VARIETIES IN
PAKISTAN
DR MUHAMMAD ANJUM ALI
MEMBER PSD-PARC

2. BOTANICAL CLASSIFICATION
Botanical Name : Oryza sativa L.
Family : Gramineae/ Poaceae
Kingdom: Plantae
Division: Magnoliophyta
Class: Liliopsida
Order: Poales
Genus: Oryza
Species Sativa

3. RICE PLANT

4. Rice plant is an annual,
2 to 6 ft (61–183 cm) tall,
round, jointed stem,
long, pointed leaves,
edible seeds borne in a dense head on
separate stalks.
Long day plant
Self pollinated

6. RICE SEED

7. STRUCTURE OF RICE SEED

8. STRUCTURE OF RICE SEED

9. PANICLE OF RICE

10. GROWTH STAGES OF RICE
Germination
Seedling growth
Tillering
Stem elongation
Booting
Inflorescence
Anthesis
Milk development
Dough development
Ripening

11. GERMINATION

12. SEEDLING GROWTH

13. TILLERING

14. STEM ELONGATION
OVERLAP TILLERING, BEFORE PANNICLE INITIATION

15. BOOTING

16. INFLORESCENCE OF RICE

17. ANTHESIS

18. MILK DEVELOPMENT

19. GROWTH STAGES

20. DOUGH DEVELOPMENT

21. RIPENING

22. FACTORS RESPONSIBLE FOR
RICE YIELD
Selection and preparation of soil
Selection of approved varieties
Seed rate
Sowing and transplantation of nursery
Irrigation on proper time
Proper use of fertilizers
Weeds management
Important diseases of rice and their control
Harmful insects and their control
Harvesting at proper time

23. RICE VARIETIES
ProvincesFine varieties Coarse varieties
Punjab Super Basmati, Basmati
2000, Basmati Pak (karnal
Basmati), Basmati 370,
Basmati 515, Basmati Kissan,
Punjab, Pakistan
KSK 282, NIAB IRRI 9, KSK
133
HYBRID.. GUARD, ARIZA,
SHAHNSHA AND MANY
OTHERS
Sind Shadasb, Khushboo, Sada
Hayat,
Kinoo 92, DR-82, DR 83,
DR-92
KPK JP-5, Basmati 385, Sawat-1, Sawat-2, IRRI-6,
KS-282, Fakhar Malakand
BalochistanBasmati-386 IRRI-6 DR-83 KS-282,

24. SOIL
Can be grown in any type of soil except
sandy soil.
Can be grown on salt effected soil where
other crops can not be grown successfully.
Clay Loam soil with optimum quantity of
organic matter and more water holding
capacity is best for rice cultivation.

25. CLIMATE
Can be grown under variety of climate,
tropical regions
cooler regions
temperate regions.
humid climate.
Best suited to regions, which have high
humidity, prolong sunshine and an
assured supply of water.

26. RICE NURSERY AND
EARLY CROP
MANAGEMENT

27. SEED RATE FOR NURSERY
(KG/ACRE)
#Rice varieties
Wet methodDry
method
Rabi
method
1IRRI 6,KSK 282, KSK
133
6-7 8-1012-15
2Supper Basmati,
Basmati 385,
Basmati 2000,
4.5-56-7 10-12

28. SOWING AND TRANSPLANTING TIME
OF NURSERY
Sr.
No
Rice varieties
Sowing timeTransplanting
time
1
Rice Hybrids (As per
recommended dates) IRRI
6,KSK 282, KSK 133
20 May to 7 June20 June 7 July
2
Supper Basmati, Basmati
385, Basmati 2000,
20 May to 20
June
20 May to 20 July
Seed with above 80% germination
Seed dressing by soaking the seed into water contain fungicide 2.5 g/ L water

29. WHAT IS THE GOAL OF CROP
ESTABLISHMENT ??
 To secure a uniform plant
population that can produce high
yields
9*9 with 2 plant per hill. 80,000 hills
per acre. 160,000 plants per acre

30. METHODS OF SOWING NURSARY
WET BED
Irrigate, plow, puddle and level the field
Prepare beds of 1 to 1.5 m width, 4-5 cm height & any
convenient length
Start preparing the seedbed 2 weeks before planting
time
Seedlings are ready for transplanting in 25-35 days.
Water the seedbed 2-3 DAS .
Maintain a water level of 2-5 cm, depending on the
height of seedlings
Apply 20-40 g urea or DAP per m
2
at 10 DAS, if
needed

31. WET-BED RICE NURSERY

32. WET-BED RICE NURSERY

33. DRY BED METHOD
Bed is prepared in dry conditions
Water the seedbed till saturation after sowing
Then water the plots periodically as seedlings
emerge & grow
This method is practiced in areas where soils
are loamy or silt loam.
Puddling is not possible.

34. DRY BED

35. DRY-BED RICE NURSERYDRY-BED RICE NURSERY

36. RABI METHOD OF NURSERY
SOWING
Practiced in D.G. khan
Areas where soil is hard
Uprooting of nursery is not possible
Nursery plots are leveled
Crop residue spread then burnt

37. RAB METHOD

38. PARA SHOOT RICE NURSERY : WHAT ARE : WHAT ARE
THE LIMITATIONS?THE LIMITATIONS?
Farmers have to buy plastic trays
Heavy rains just after SB may disturb
the distribution of broadcasted
seedlings

39. PARA SHOOT RICE NURSERY

40. PARA SHOOT RICE NURSERY
TRANSPLANTING WITH MACHINE

41. PARA SHOOT NURSERY
TRANSPLANTING

42. IRRI: Rice Production Course
Source: Dr. Sumith, RRDI,
SL
PARA SHOOT NURSERY
TRANSPLANTING

43. TRANSPLANTING :
MOST COMMON METHOD IN
SMALL FARMS OF ASIA

44. TRANSPLANTING OF RICE
IRC 2003:1914

45. TRANSPLANTING: CRITICAL FACTORSTRANSPLANTING: CRITICAL FACTORS
•Proper nursery management
•Careful handling of young seedlings for fast
revival and early growth after TP
•Shallow transplanting at 1-2 cm depth
•Optimum plant-to-plant spacing: 20 x 20 cm to
25 x 25 cm
•Optimum number of seedlings: 1-2 hill
-1
IRRI: Rice Production Course

46. IRRI: Rice Production Course
CAREFUL HANDLING OF CAREFUL HANDLING OF
SEEDLINGSSEEDLINGS

47. MANUAL TRANSPLANTING: WHAT ARE
THE ADVANTAGES
Good head start for
plant growth over
weeds
Shorter duration in
main field
Easy to maintain
uniform plant spacing
& population, if
planted in rows

48. MANUAL TRANSPLANTING:
WHAT ARE THE CONSTARINTS
 Tedious & labor
intensive, > 30 PD ha
-1
 Difficult to find
labor to plant on time
 Drudgery & back
problem
 Poor plant population due to contract TP
on area basis

49. IRRI: Rice Production Course
MANUAL TRANSPLANTER

50. IRRI: Rice Production Course
MANUAL TRANSPLANTER

51. MECHANICAL
CHINESE &
JAPANESE
TRANSPLANTERS

52. DIRECT SEEDING OF RICE: DIRECT SEEDING OF RICE:
WHY?WHY?
•To reduce labor input
•To tackle labor
shortage & high
wages
•To establish crops on
time
•To maintain optimum
plant population
IRRI: Rice Production Course

53. DIRECT SEEDING OF RICE:
INCENTIVES
Increasing water crisis is forcing farmers and
researchers to find out ways to decrease
water use in rice production.
In Asia, irrigated agriculture accounts for 90%
of total diverted freshwater, and more than
50% of this is required to irrigate rice.
Direct seeding offers a promising solution for
this by saving water and labor
Direct seeding is a potential alternative to the
traditional production system
 Reduced cost: US$ 60-80 per ha
 Less methane emission: DDS < WDS < TP

54. DIRECT SEEDING REQUIREMENTSDIRECT SEEDING REQUIREMENTS
•Good Land Prepration &
leveling
•Furrows to drain water
•Saturated soil (WDS) &
moist soil (DDS) for first 7-
10 days
•Varieties: early seedling
vigor, fast canopy dev.,
non-lodging
•Quality seed
•Effective weed control:
cultural, mechanical,
herbicides
IRRI: Rice Production Course

55. Level field for DDSLevel field for WDS
WELL-PREPARED AND LEVELED
FIELDS FOR DIRECT SEEDING

56. DIRECT SEEDING METHODS
•Wet direct seeding (WDS): puddled soil,
broadcast- or row-seeded
>Surface WDS
>Subsurface WDS
>Water seeding
•Dry direct seeding (DDS): dry/moist soil,
broadcast or drilled in rows
IRRI: Rice Production Course

57. IRRI: Rice Production Course
Drum seeder,8 kg wt + 12 kg seed

58. Drum seeder
Seed hoppers
Seed holes

59. DRY SEEDING
Used in rainfed areas
Dry seed
Seed rate 75 kg ha
-1
Germination with rainfall;
drought
High pest incidence
SEEDING BEHIND PLOW Machine seeding
DRY BROADCASTING

60. BED PLANTING

61. TRANSPLANTING
SEEDLINGS ON BED
•Good CE, but more labor
•Good plant growth & uniform tillering
•High yield as that of TPR
•Less water use (by 20-30%) than that of
TPR

62. DSR-B: DRY DRILL SEEDING ON BEDS
•Fast & efficient seeding, but poor CE
•May need saturated soil for the first 25-30
days
•Micro-nutrient deficiency: Fe, Zn, Cu, etc.
•Severe weed infestation, needs effective
herbicides
•Termite problems
•Saving in water (~ 20-30%)
•Conserves rain water & avoids flooding

63. WATER MANAGEMENT
1.Judicious use of water is necessary
2.At transplanting and one week after depth of water 3-
4 cm
3.Higher water depth is harmful
4.Lower water depth cause drying
5.Seven days after transplanting depth of water should
be 8 cm
6.Water should remain standing in field continuously for
25-30 days.

64. FERTILIZER MANAGMENT
Adequate and timely application of fertilizers is
essential
Soil analysis should be done
Incorporation of green manure crop before
transplanting to increase organic matter
All of P and k and half of the N is incorporated
into soil at the last ploughing
Remaining N is top dressed after 30-35 days

65. QUANTITY OF FERTILIZER (KG\ACRE)
Type of varietiesN P K Amount of fertilizer
at the time of
puddling
After
transpla-
nting
Hybrids/ IRRI-6,
KSK 282, Niab IRR-
9, KSK 133
(LCC Method)
69 41 32 1.5 Bag Urea+4.5
Bag SSP+1.25 Bag
Potassium Sulphate
1.5 Bag of
urea after 30-
35 days of
urea
transplanting
Super Basmati,
Basmati 2000,
Basmati Pak (karnal
Basmati), Basmati
370, Basmati 515
57 32 25 1 Bag Urea+3.5 Bag
SSP+ Bag Potassium
Sulphate
0.5 Bag of
urea after 30-
25 days and
¾ bag of
urea
transplanting

66. WEEDS MANAGEMENT
15%-20% losses due to weeds
Some time up to 50%
Three groups of weeds in rice
Weeds of grass family
Weeds of sedge family
Broad leaf weeds

67. WEEDS OF GRASS FAMILY
Swanky grass (Echinochloa colon)
Dhedan ( Echinochloa crusgalli)
Khabal grass (Cynodon dactylon)
Narro (Paspalum distichum)
Weeds of sedge family
Ghoein (Cyperus difformus)
Bhoein (Cyperus iria)
Deela (Cyperus rotundus
Broad leaf weeds
Mirch boti (Sphenoclea zeylanica)
Chopti (Marsilea minuta)
Darai boti (Fclipta bprostata)

68. INTEGRATED WEED MANAGEMENT
(IWM)
1.IWM is aimed to reduce weed population to the level at which there
would be no economical losses of crop.
2.Effective IWM combines preventive, cultural, mechanical and biological
weed management methods in an effective, economical and
ecologically safe manner.
3.weed management technologies can optimize rice production.
4.Holistic multi-disciplinary integrated approach is necessary.
5.combination of various weed management methods together is called
integrated weed management (IWM).
6.Weeds are allowed to emerge and are then killed during tillage
operations.
7.First weeding should be done between 15 to 21 days after germination.
Second weeding is done 30 to 45 days after first weeding.
8.Application of mulch reduces weed growth and conserve moisture and
fertilizers.
9. Use of weed free seed material is recommended for better weed
management.

69. INTEGRATED WEED MANAGEMENT
(IWM)
Maintaining 5–7 cm water depth and avoiding drainage prevents
germination of weed seeds.
 Azolla can suppress the weed growth by reducing sunlight and
aeration.
 Herbicide should be applied when there is a thin film of water in the
field
Application of pendimethalin 1.0kg/ha on 5 days after sowing
 Pretilachlor + Safener (Sofit) 0.45kg/ha on the day of receipt of
soaking rain followed by one hand weeding on 30 to 35 days after
sowing effectively controls weeds in kharif season

70. INSECTS
MANAGEMENT

71. DARK-HEADED STEM
BORERLarva
•Neonate - grayish white with a large head.
•Head and prothoracic shield are black.
•Body dirty white with five longitudinal
stripes of grayish violet or purplish brown
situated mid- dorsally, latero-dorsally, and
laterally.
Adult
•Adults brownish yellow.
•The center of the forewings has dark
markings of silvery scales or 6-7 tiny
black dots.
•The hind wing has a lighter color.
DARK-HEADED STEM BORER

72. •Larva
The larva is whitish to light yellow. A
full-grown larva is 25 mm long. The
larva has no body marks.
•Pupa
The fresh pupa is soft-bodied and
whitish. It grows up to 25 mm in
length. With age, it turns brown.
•Adult
The male and female adults are
immaculately white in appearance.
They have a tuft of long hairs on the
thorax. The male is smaller than the
female.
WHITE STEM BORER
(SCIRPOPHAGA INNOTATA)

73. YELLOW STEM BORER
Most destructive pest.
Attack all stages of the rice plant
1% to 19% yield loss in early planted rice
crops and
38% to 80% yield loss in late-planted rice.
Low infestations by stem borers may not
result in yield loss because of plant
compensation.
Sprays for stem borer control carried out
when whiteheads are visible will not result in
any economic gain.

74. PLANT
HOPPERS
Brown plant hopper (BPH) (Nilaparvatha lugens)
White backed planthopper (WBPH) (Sogatella furcifera)
Brown planthoppers (BPH) suck the
sap of the leaf blades and leaf sheaths,
causing the yellowing of the plants.
Hopperburn or complete drying of the
plants is observed at a high population
density of the insects. At this level, the
loss is considered 100%.

75. Eggs
are crescent-shaped, 0.99 mm long and 0.2 mm
wide. Some of the eggs are united near the base
of the egg cap and others remain free. When
freshly laid, the eggs are whitish, but later
become darker. Before egg hatching, two distinct
spots appear, representing the eyes of the
developing nymph.
Nymphs
The newly hatched nymphs are 0.91 mm long
and 0.37 mm wide. The head is triangular with a
narrow vertex. The body is creamy white with a
pale brown tinge. The nymphs molt five times.
The fully developed nymph is 2.99 mm long and
1.25 mm wide. There is a prominent median line
from the base of the vertex to the end of the
metathorax where it is the widest. This line
crosses at a right angle to the partition line
between the prothorax and mesothorax.

76. •Leaf hoppers adult and nymphs
suck the sap from the leaves
which is characterized by small
scratch like marks on the leaf
due to chlorophyll removal.
Leaf hoppers
Green leaf hopper
Nephotettix virescens
N. nigropictus
Zigzag leaf hopper
Racilia dorsalis
EIL 10 GLH/hill at vegetative stage
20 GLH/hill at flowering stage

77. INTEGRATED
DISEASE
MANAGEMENT IN
RICE

78. MAJOR DISEASES OF RICE
•Blast (Pyricularia oryzae)
•Brown spot (Helminthosporium oryzae)
•Stem rot (Sclerotium oryzae)
•Bacterial leaf blight (Xanthomonas oryzae)

79. SYMPTOMS OF BLAST DISEASE

80. BLAST DISEASE
•Most plant parts are susceptible to infection
except the roots.
•Disease usually develops during seedling,
tillering (leaf blast) and at heading (panicle
blast).
•The initial infections start as small water
soaked areas on young leaves and enlarge into
diamond shape with a blue gray cast which are
the fungal spores. Lesions often dry out and
turn tan with a brown border. Lesion shape and
size can vary.

81. Head infections develop at the joint just below
the head (neck blast) or on individual panicle
branches (panicle blast). The head can break off
at neck lesion can cause rotten neck blast.

82. The fungus produces many spores ,on
stalk like structures called sporangia, in
the presence of a favorable environment
and a susceptible host and causes
numerous new infections in the field and
neighboring fields. They are carried by
wind and water over long distances.

83. MANAGEMENT
Blast development is favored by thick
stands and high nitrogen rates which
increase canopy thickness resulting in
higher moisture levels but is most severe
under upland or drained conditions. Other
conditions that favor blast are sandy soils
and fields lined with trees.

84. MANAGEMENT
•Plant varieties resistant to blast.
•Avoid late planting.
•Plant as early as possible within the recommended
planting period.
•For leaf blast, re-flood if field has been drained. Maintain
flood at 4 -6 inches to ensure soil is covered.
•Do not over fertilize with nitrogen.
•Apply a fungicide if necessary.

85. BROWN SPOT

86. MANAGEMENT OF BROWN
SPOT
•Treat the seeds with 0.2% Thiram
•Avoid water stress
•Give balanced nutrition
•Use resistant varieties
•Spray Tricyclazole

87. BACTERIAL BLIGHT
• Symptoms
•Small, green water-soaked spots develop at the tips
and margins of fully developed leaves, and then
expand along the veins, merge and become chlorotic
then necrotic forming opaque,
• White to grey colored lesions that extend from leaf tip
down along the leaf veins and margins. Both bacterial
blight and bacterial leaf streak can occur
simultaneously and are difficult to distinguish

88. CAUSED BY XANTHOMONAS
ORYZAE

89. FACTORS FAVORING
DISEASE DEVELOPMENT
Presence of weeds
Presence of rice stubbles and ratoons of
infected plants
Presence of bacteria in the rice paddy and
irrigation canals
Warm temperature, high humidity, rain
and deep water
Over fertilization
Handling of seedlings at transplanting

90. MANAGEMENT PRINCIPLES
•Practicing field sanitation such as removing weed
hosts, rice straws, ratoons, and volunteer seedlings is
important to avoid infection caused by this disease.
•Likewise, maintaining shallow water in nursery beds,
providing good drainage during severe flooding,
plowing under rice stubble and straw following harvest
are also management practices that can be followed
•Proper application of fertilizer, especially nitrogen, and
proper plant spacing are recommended for the
management of bacterial leaf blight

91. HARVESTING
Harvesting is the process of collecting
the mature rice crop from the field.
•Cutting: cutting the panicles and straw.
•Hauling: moving the cut crop to the
threshing location.
•Threshing: separating the paddy grain
from the rest of the cut crop.
•Cleaning: removing immature, unfilled and
non-grain materials.
•Field drying: (optional) leaving the cut crop
in the field and exposing it to the sun for
drying.
•Stacking / Piling: (optional) temporarily
storing the harvested crop in stacks or
piles.

92. GOOD HARVESTING PRACTICES
Goals of good harvesting:
•maximize grain yield
(minimize losses)
•minimize grain damage
•Minimize quality
deterioration
•Heat build up from mold and
insect development
•Discoloration/Yellowing from
heat build-up
•Cracking from re-wetting of
dried grains
•Loss of vigor
•Reduced head rice yield
•Shattering losses
At harvest the quality of rice is
best. From then on it can
deteriorate quickly:

93. HARVESTING SYSTEMS
1. MANUAL SYSTEM
•Manual operation
sometimes using
tools
•Labor
requirement: 48
person days / ha

94. Harvesting systems
2. Manual cutting / machine threshing
Labor requirement: 28 person days/ha
Capital cost appr.: US$ 1000
Optional:
Winnowing
or
cleaning

95. HARVESTING SYSTEMS
2. MACHINE CUTTING / MACHINE
THRESHING
•Capacity reaper:
•Capacity thresher:
•Capital cost approx.: US$ 2,500
Optional:
Winnowing
or
cleaning

96. HARVESTING SYSTEMS
4. COMBINE HARVESTING
•Cutting, hauling,
threshing, cleaning in
one combined
operation
•Capacity: > 0.5 ha/h
•Labor requirement: 1
Operator
•Capital cost: > $
250,000

97. WHEN TO HARVEST
Harvest rice when:
• 20-25% grain moisture
•80-85% straw colored
and
• the grains in the lower
part of the panicle are in
the hard dough stage
• 30 days after flowering

98. MANUAL CUTTING AND HAULING
•Capacity: 0.07 ha/person day
•Advantages
•effective in lodged crop
•less weather dependent
•Problems
•high labor cost
•labor dependent, competes with
other operations in peak season
•winnowing/cleaning necessary

99. MECHANICAL REAPING
•Capacity: 2-4 ha/d
•Advantages
•Fast cutting
•Problems
•Places crop in window
back in the field
•Problem with lodged
crop
•Complex cutter bar and
conveying mechanism

100. MANUAL THRESHING
•Capacity: approximately 15
person days/ha
•Threshing by impact
•High shattering losses
•Pre-drying might be needed

101. PEDAL THRESHER
•Capacity:
•Principle
•Wire loop threshing drum
•Mainly combing the grains
off the straw, some threshing
by impact
•Advantages
•Maintains the straw
•Disadvantage
•Needs winnowing after
threshing
Wire loop threshing drum

102. WINNOWING
•Principle: lighter materials
are blown away by air
•Removes chaff, straw and
empty grains
•Hand or mechanical
winnowing
•Does not work for
materials heavier than
grain (dirt, stones)

103. CLEANING
•Combination of fan and
oscillating sieves
•Air delivered by fan
removes lighter materials
•Top sieves with large holes
remove larger straw
particles
•Bottom sieves with smaller
holes remove small seeds
(e.g. weed seeds)

104. COMBINE HARVESTING
•Features
•capacity: 4-8 ha/day
•combines cutting, threshing,
cleaning and hauling
•tracks for mobility in wet fields
•Advantages
•high capacity
• low total harvest losses
•Disadvantages
•Requires relatively large field
sizes
•Problem in terraced fields

105. STRIPPER HARVESTING
•Capacity: 1ha/day
•Advantages
•strips and collects grains only
•less material to handle
•Problems
•problems in wet soils and lodged
crop
•straw treatment
•does not work well with long
straw
•complex machine
•skills required
Despite strong promotion in SE-Asia the
stripper harvester has not gained wide
popularity because of its problems in
less favorable harvesting conditions

106. LOSSES DURING CUTTING
•Shattering loss = premature shedding of mature
grains from the panicle caused by birds, wind, rats, and
handling operations. Certain rice varieties shatter more
easily than others.
•Lodging loss = plants with mature grains in the
panicles fall on the ground making the grains difficult to
recover.
•Standing crop loss = standing plants with mature
grains are left standing in the field after harvesting
operations as a result of oversight, carelessness or
haste.

107. LOSSES DURING THRESHING
•Separation loss or “blower loss” = mature
grains that are mixed with straw or chaff during
the cleaning operation.
•Scatter loss = mature grains that are scattered
on the ground during the threshing and
cleaning operation.
•Threshing loss = mature grains that remain
attached to the panicle in the straw after
completion of the threshing operation. High
threshing efficiency will lead to low threshing
loss, and vice versa.

108. RECOMMENDATIONS FOR
OPTIMIZING QUALITY
Harvest at the right time and moisture
content
Avoid stacking the cut crop in the field
Avoid delays in threshing after harvesting
Use the proper machine settings when
using a threshing machine
Clean the grain properly after threshing
Avoid delay in drying after threshing

109. TIPS FOR MANUAL THRESHING
•Thresh as soon as
possible after cutting
•Hand thresh at lower
moisture
•Place a large canvas
under the threshing
frame to minimize
shatter loss

110. TIPS FOR MACHINE THRESHING
•Thresh as soon as
possible after cutting
•Level the thresher
•Set machine
correctly
•drum speeds in thresher
(600rpm)
•air flow in the cleaner
•angle in the cleaner sieves

111. TWO COMMERCIAL SYSTEMS FOR HYBRID
RICE

112. REQUIREMENTS FOR 3 LINES IN CMS
SYSTEM
A-line
Stable Sterility
Well developed floral traits for outcrossing
Easily, wide-spectum, & strongly to be restored
B-line
Well developed floral traits with large pollen load
Good combining ability
R-line
Strong restore ability
Good combining ability
Taller than A-line
Large pollen load, normal flowering traits and
timing

113. TGMS AND TWO-LINE HYBRID
Based on the
discovery of
P(T)GMS mutant
Male sterility
controlled by 1 or 2
pairs of recessive
gene(s)
Fertile
S-line
Multiplication
Critical Fertility Point
Critical Sterility Point
Reproductive Upper Limit
Reproductive Lower Limit
Sterile
F1 Seed
Production
Partial Sterility
Model of Sterility / Fertility Expression for TGMS Rice
Temperature
low
high

114. ADVANTAGE & DISADVANTAGE OF 2-
LINE HYBRID RICE SYSTEM
Advantages
Simplified procedure of hybrid seed production
Multiple and diverse germplasm available as parents
Any line could be bred as female
97% (2-line) vs 5% (3-line) of germplasm as male
Increased chance of developing desirable & heterotic hybrids
Multiple cytoplasm courses as female parents
Disadvantages
Environmental effect on sterility could cause seed purity
problem

115. THANKS