What is Hybridization?
• The offspring that is obtained by crossing two genetically dissimilar
homozygous parents is called hybrid and the process of producing
hybrid is called hybridization.
• Yuan Longping, the "Father of Hybrid Rice", may be the most
famous in research on hybrid rice. In the 1970 s, he made his
discovery of the genetic basis of heterosis in rice. This was a unique
discovery because it had been previously thought that heterosis
was not possible for self-pollinating crops such as rice.
• To create variability
• To increase the yield of grain
• To increase grain quality
• To develop early maturity variety
• To develop disease resistant variety
• To develop insect and pest resistant variety
• To improve cooking characteristics
• Terminal panicle which bears perfect flower.
• Sessile,bi-sexual,self pollinated flower.
• Flower having six stamens.
• Flower surrounded by lemma and palea.
• Gynocium consists of carpel-1,superior ovary and one chambered
• Most of the flowers bloom between 2-4 days.
• Blooming of the spikelets starts from panicle apex and proceeds
• Pollen shed at the time of flower opening.
• Stigma remains receptive for 4-5 days.
• Pollen preservation possible for 24 hours at 54 degree F at 95% humidity
• Fertilization completes within 3 hours after pollination
1. Selection of female plants
• Insect and disease free healthy plant
• Selection of flowers expected to open by next morning
• Removal of immature and open flowers
• Purpose of emasculation to prevent pollination
• Selection of panicles expected to open in the morning
• Selection of spikelets whose anther length about 60%
• Lemma and palea need to cut at a place 20% bellow from the tip
• Stamens need to remove one by one with sterized needle or forceps
• Best time : afternoon
• Bagging of emasculated flowers with polythene
prevented of pollen
vacuuming of anthers
involves an aspirator
and high speed suction
of pollen from the
anthers of flowers with
a minimum damage to
• Process of collecting anther and pollen grains of desired male parent and
putting in the stigma at the emasculated flower of desired female parent
• Done in the next morning when the stigma is receptive
• Collection of yellow and turgid anthers from desired male plant and
putting them in bright sunlight for 15 minutes
• Temporary removal of bag from female plants and pollination is done by
dusting pollens over stigma surface of emasculated buds
• Sometimes whole anther is inserted inside the florets with the help of
• Fixation of bamboo stick
• Top of the plants with bud inside the bag
• Two james clip through holes
• Exchanges of gases
• Stop the visit of insect
• After bagging tag bear following information:
Cross combination (BR3 x BRRI dhan 29)
Date of emasculation
Date of pollination
Numbers of buds pollinated
Signature of the breeder
• In agriculture, it is vitally important to maintain genetic diversity to
obtain the health and longevity of a crop.
• As with other types of hybrids, hybrid rice typically displays
• Green Revolution popularized the use of conventional
hybridization to increase yield by creating "high-yielding varieties".
• Often the handful of hybridized breeds originated in developed
countries and were further hybridized with local varieties in the rest
of the developing world to create high yield strains resistant to
local climate and diseases