WELCOME TO

PRESENTATION

ORGANIZED BY : SHAHANAZ PARVEEN

ASSISTANT PROFESSORDEPT. OF GENETICS AND PLANT BREEDINGSHER-E-BANGLA AGRICULTURAL UNIVERSITY

HYBRIDIZATION TECHNIQUE IN RICE

Group name: GladiolousPrepared by :

BILASH CHANDRA MANDAL 10-03863 MITA RANI DAS 10-03864 IMRAN BIN ISLAM 10-03865 URMI PAUL 10-03868 M.ZUNAID HABIB 10-03870 ROUNAK FATIMA 10-03874 MD. TAREQ HASAN 10-03884

DISCUSSION TOPICS

•Definition•Objectives•Materials Required•Floral Biology•Steps in Hybridization

What is Hybridization?

Hybrid

Homozygous parents

Genetically Dissimilar

Crossing

Hibridization

• 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.

Objectives

• 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

MATERIALS• Rectified Spirit • Needle• Scissor • Forceps• James Clips• Tags• Polythene Bags • Bamboo Sticks• Conical Flask• Threads

FLORAL BIOLOGY• 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 hypogynous.• Most of the flowers bloom between 2-4 days.• Blooming of the spikelets starts from panicle apex and proceeds downward.• 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

Diagrams of Floral Biology

STEPS IN HYBRIDIZATION

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

2. EMASCULATION • 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

EMASCULATION PROCESS

Diagrams of emasculatio

n process

Mechanical emasculation

Mechanically prevented of pollen

transfer

Time saving, extensive,quite

cheap

vacuuming of anthers involves an aspirator and high speed suction of pollen from the

anthers of flowers with a minimum damage to the

stigma.

3. POLLINATION

• 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 forceps

BAGGING

• 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

TAGGING

• After bagging tag bear following information:

Cross combination (BR3 x BRRI dhan 29)Date of emasculationDate of pollinationNumbers of buds pollinatedSignature 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 heterosis

• 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