1. SUBMITTED TO:
Dr. UMESH KUMAR sir
Assistant Professor
Dept of Genetics and Plant Breeding
SUBMITTED BY:
NAA/18-17
NAA/18-32
NAA/18-53

2.  Prof. Yaun Long Ping is the father of hybrid rice in
China
 Hybrid rice gives 1.0 ton more yield than the best
variety available
 The first rice hybrid has been developed in the country
by ANGRAU i.e., APHR-1 and APHR-2

3.  Hybrid rice can be produced by 3 different methods
1) Three line system
2) Two-line system
3) By using chemical emasculants

4.  By using CGMS system. In this method, three
different lines are used i.e.,
1) A-line or male sterile line
2) B-line or maintainer line
3) R-line or restorer line

6.  This method hybrid rice seed production involves the
use of both PGMS or TGMS system
 Any normal line can used as restorer line
 Maintainer line is absent

8.  Chemicals which kill or sterilize the male gametes
with no effect on female gametes can be used to
emasculate female parental line
 In China: these emasculants commonly used in hybrid
seed of rice
 In India: not used for Hybrid seed of rice but used in
academic studies
 Chemical used as potent gametocides are ethrel,
maleic hydrazide etc

9.  Hybrid rice seed is produced by CGMS system
 Involves two steps:
Maintenance of parental lines (A-line; B-line and R-
line)
Commercial hybrid seed production (A*R)

10.  Land Requirement: The same crop should not be grown on the
same piece of land for the last one season
 Isolation Requirement: The hybrid paddy fields
Certified seed – 200 meters
Foundation seed – 100 meters
 Brief Cultural Practices: Follow all recommended package of
practices and take necessary prophylactic measures to raise a
good crop
 Planting Ratio: The planting ratio of male and female are 2:6; 2:8
or 3:8

11.  Number of Field Inspections: Minimum 4 field
inspections must be held
1st field inspection – before flowering
2nd and 3rd field inspection – during flowering stage
4th field inspection – before harvesting
 Roughing: Removal of off types and plants which are
infected with stem borer and diseased plants like
paddy bunt

12.  Paddy is highly self pollinated crop and extent of
natural cross pollination is very less,
 To increase out crossing certain methods should be
followed:
1) Flag Leaf Clipping
2) GA3 Application
3) Rope Pulling

14.  Flag leaves are taller than panicles and are the main
obstacles for pollen dispersal and cross pollination
 Hence the flag leaves should be removed so as to
improve cross pollination and seed set
 The flag leaves should be clipped one or two days
before heading so that it enhances uniform pollen
movement and wide dispersal of pollen grains to give
higher seed set
 First cut the flag leaf of the main tiller at the flag leaf
joint and use it as a guide in clipping the remaining
plants

15.  The flag leaves should be cut to half or 2/3 of the blade
from tip
 Do not clip the flag leaves in plants which are infected
with bacterial leaf blight or sheath blight
 The cut leaves can infect other plants or contaminating
tools used for flag leaf clipping can spread infection.
 The infected plants may be clipped after completing
the clipping of healthy leaves

16. Application of GA3
 Increases the internodes length
 Increases the duration of floret opening and stigma
receptivity
Spraying of GA3 should be done twice
 1st – 15-20% of the plants started heading with 40% of
chemicals
 2nd – 50% flowering with 60% of chemicals

18.  Rope pulling should be done during the peak
flowering time, which helps in shaking of the male
plants and dispersal of pollen grains
 Rope pulling should be done daily during peak
flowering stage at 8:30 AM and it should be repeated
3-4 times a day at an interval of half an hour

19.  Harvest the male row first and remove them from
fields so as to avoid mechanical mixture.
 Then harvest female rows
 Precautions should be taken while harvesting, not mix
male and female plants
 Threshing should be done on clean floor and should
be winnowed before storage

20.  Depending on the management practices adopted and
the potentiality of the parental line in the seed yield
may be in the range of 0.5-1.5 t/ha.

21. THANK YOU