Hybrids in Annual Crops

Hybrids in Annual Crops


Hybrids in Annual Crops:
  • The main advantage of F1 hybrids is the unique combination of appreciable vigour and uniformity.
  • Apart from this, F1 are dwarf, compact with basal branching, free- flowering with larger flowers, prolonged duration of flowering and may have insect- pest and disease resistance.
Marigold
  • Marigold is a member of Asteraceae family.
  • It is native to Central and South America, especially Mexico.
  • 'Pusa Basanti Gainda' (yellow coloured flowers) and 'Pusa Narangi Gainda' (orange coloured flowers) have been developed in India through pedigree method of breeding in African marigold.
  • 'Pusa Arpita' has been developed through selection in french marigold.
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Pusa Arpita
  • F1 Hybrid seeds in marigold were produced by using apetalous male sterile lines. Tester parents were maintained as inbred lines. Pusa Shankar- 1 was developed at IARI, New Delhi.
  • Male sterile lines and tester parents were grown in separate polyhouses.
  • Apetalous male sterile lines were maintained. These were exploited by making crosses with the respective tester parents from 9 a.m. to 2 p.m. by taking pollens from desirable male parents in a petri dish and dusting it on male sterile flowers with the help of a soft brush.
  • The flowers were bagged with perforated butter paper bags.
  • In French marigold and African marigold, Line x Tester was carried out by using tester parents.
  • F1 hybrid seeds were collected and sown for evaluation in the subsequent seasons.
Antirrhinum
  • Antirrhinum belongs to family Scrophulariaceae and is a native of Southern Europe.
  • Flower form is controlled by a single dominant gene. F1 hybrid.
  • Seeds in antirrhinum were produced by using hand emasculation technique.
  • The female parent was emasculated by removing anthers from the florets when the lowermost floret is fully opened.
  • Emasculation is done on lower one third length of the spikes and rest of the spike is chopped off.
  • With the help of a pair of forceps, the petals were peeled and anthers were removed and bagged with muslin cloth bag.
  • Fresh flowers should be plucked from intended male parent which have been previously bagged and pollen dusted on the stigmas of emasculated flowers.
  • Crossing is done during 10 am to 12 noon.
  • The pollinated spike is then bagged with perforated butter paper bag to prevent cross pollination.
  • The hybrids seeds of all the crosses are collected when spikes are matured.
  • F1 hybrid seeds are collected and sown for evaluation in the subsequent seasons.
  • 'Tetra Giant' variety developed by polyploidy has higher number of flowering stems with large, deeper coloured flowers which are longer lasting than diploid counterpart.
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Pansy
  • Pansy belongs to the family Violaceae.
  • In Pansy, selections were put to evaluation and maintained as pure lines F1 hybrid seed in pansy was produced by using hand emasculation technique and making crosses among the selected tester parents.
  • The female parent was emasculated by removing anthers from the flowers when the flower starts showing colour.
  • The emasculated flower is then bagged with perforated butter paper bag to prevent cross pollination.
  • Crossing was done during 10 am to 12 pm, by taking pollens from desirable male parents in a petri-dish and dusting it on male sterile flowers with the help of soft caramel brush.
  • The flowers were bagged with perforated butter paper bags.
  • The pollinated flowers were tagged showing male, female parents and date of crossing.
  • Same procedure of crossing with the same male parent was repeated the next day to ensure proper pollination and seed set.
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China aster

  • China Aster belongs to family Asteraceae, is native to China.
  • Four varieties namely, Kamini, Poornima, Shashank and Violet Cushion have been developed by pedigree method.
  • Appreciable heterosis was observed for all the characters.
  • Based on the economic characters like flower size, flower per plant and stalk length, three crosses Shell Pink Azure Blue, AST-20 Azure Blue and AST-20 AST-16 were recommended for exploitation of heterosis on commercial scale.

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A. Kamini: Variety developed at IIHR, Bangalore in 1992 through Pedigree selection between AST-6 X AST-36
B. Poornima: Variety developed at IIHR, Bangalorein 1992 through Pedigree selection between AST-29 X AST-3
C. Shashank: Variety developed at IIHR, Bangalore in 1994 through Pedigree selection between Local Pink X AST-2
D. Violet Cushion: Variety developed at IIHR, Bangalore in 1994 through Pedigree selection between AST-6 X AST-2
Petunia
  • Petunia, a member of Solanaceae family, is native of South America.
  • A large number of F1 hybrid varieties have been developed in Single and double petunias of multiflora and gradiflora types in the U.S.A., U.K. and Japan.
  • In India, a number of hybrids have been developed by Indo- American Hybrid Seeds Company, Bangalore
Balsam
  • Impatiens balsamina, is native of India, China and Malaysia.
  • It belongs to Balsaminae.
  • One pink coloured, double flowered seedling selection has been maintained and the seed is being produced every year in Nauni.
Gloxinia
  • Sinningia speciosa which normally does not produce seeds under Nauni- Solan conditions, seed was produced through artificial pollination and from the first progeny one variant which produced large red flowers with white frilled margins was obtained.
  • In Gomphrena globosa two selections were made in 1996 and evaluated in Nauni.
  • Similarly, in Salvia (Salvia splendens) two selections red and purple have been maintained.
  • Many seedling selections in Phlox (Phlox x drummondii) have been maintained and are being evaluated.

Last modified: Wednesday, 16 January 2013, 5:24 AM