BASIC CONCEPTS OF PLANT BREEDING : BASIC CONCEPTS OF PLANT BREEDING A.K. Chhabra Copyright of original figures used in this presentation from other sources is duly acknowledged and the copyright remains with its original creator. These have not been used for commercial purpose but for educational use only. Floral Biology : Floral Biology BREEDER’S KIT : BREEDER’S KIT Needles : Required to open small buds and separating the floral parts.
Brushes: Camel hair brushes of size 1, 2, 3 or 4 or bigger (depending upon flower size) for collection of pollen and transfer to stigma. Sometimes cotton is also used for this purpose.
Bags: Parchment paper bag, khaki cloth bags, muslin cloth bag, and paper bags of different sizes for different crops. These are used to avoid cross-contamination with pollen of unwanted genotype.
Alcohol or methylated spirit: A small vial of alcohol or methylated spirit is required to sterilize forceps, scissors, needles, brushes etc.
A Good Quality Microscope is required in the lab to study cell division, pollen viability and germination etc.
Tags: Paper, cardboard or aluminum tags are required for labeling the crossed /emasculated buds in the field. In the case of paper or cardboard tags, they have to be dipped in wax after labeling and tags are tied in bamboo sticks.
Lead pencil: Required to write on the paper tag. This is preferred over permanent marker pen because of its durability under all kinds of harsh weather like high temperature and rain.
Colored thread: Colored thread is required to tie the bud that has been emasculated. Different colors may be used to denote different dates of emasculation. This helps in easy trace out of flowers ready to pollinate on a particular date.
Meter scale: Required for plant and other measurements in the field.
Petri plate: A Petri plate is required to collect the pollen grains in some of the crops like Sunflower. Pollen is collected in mass and applied using cotton.
Field note books: Field note books are required to note down daily observation in the field, regarding germination, flowering, morphological description, initial and final stand etc.
Other Accessories: Besides all these breeders of different crops may require some specialized items. For example, cotton breeder may require Paper straws to emasculate flowers if he/she is using paper straw method which is common at many places. Hot water thermos / cold water containers may be required if breeder is applying these treatments for emasculation (e.g. in rice). A portable phase contrast microscope is also required to test pollen viability under field conditions while conducting pollination in the emasculated flowers and to see fertility/sterility behaviour of CMS and restorer lines in seed production programme. Slide 4: Flower Structure Slide 5: END SHOW Generalized Flower Structure Reproductive organs-somatic as well as reproductive cells participate in APOMIXIS Slide 6: END SHOW Flower Structure Pollination generally occurs in an apomictic flower but fertilization does not take place…….. Slide 7: Gametes and other somatic cells ??? END SHOW Antipodal cells Egg Cell Polar nuclei Slide 8: ALTERNATION OF GENERATION
Sporophytic Angiosperm follows alternation of generation FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER Slide 12: PERFECT FLOWER Self-pollination
Apomixis Which type of flower leads to apomixis ? Slide 13: PISTILLATE
FLOWER Which type of flower leads to apomixis ? Cross-pollination
Apomixis Slide 14: Which type of flower leads to apomixis ? STAMINATE FLOWER Apomixis
v.v.rare Slide 15: Self-pollination
Apomixis Apomixis Cross-pollination
Apomixis Which type of flower leads to apomixis ? go back Slide 16: ? Complete / Incomplete / Perfect / Imperfect / Hermaphrodite / Bisexual / Staminate / Pistillate / Unisexual Click to get answer.... Slide 17: Apomixis Complete / Incomplete / Perfect / Imperfect / Hermaphrodite / Bisexual / Staminate / Pistillate / Unisexual Slide 18: ? Complete / Incomplete / Perfect / Imperfect / Hermaphrodite / Bisexual / Staminate / Pistillate / Unisexual Click to get answer.... Slide 19: Complete / Incomplete / Perfect / Imperfect / Hermaphrodite / Bisexual / Staminate / Pistillate / Unisexual Apomixis Slide 20: ? Complete / Incomplete / Perfect / Imperfect / Hermaphrodite / Bisexual / Staminate / Pistillate / Unisexual Click to get answer.... Slide 21: Complete / Incomplete / Perfect / Imperfect / Hermaphrodite / Bisexual / Staminate / Pistillate / Unisexual Apomixis FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER Slide 35: END SHOW MODES OF POLLINATION Slide 36: END SHOW Detection of Mode of Pollination Slide 37: END SHOW Determination of apomixis aa AA CLICK HERE Slide 38: REPRODUCTIVE CHARACTERS Slide 39: Amount of Cross-pollination Slide 40: Modes of reproduction Modes of Reproduction Sexual Asexual Apomixis Vegetative Slide 41: It is uniparental
Also called somatogenic reproduction
No fusion of gametes
Meiosis is absent, only mitosis is present
Haploid-diploid alternation does not occur.
Quick method of multiplication
Parent produces large number of individuals Asexual Reproduction AMPHIMIXIS-SEXUAL REPRODUCTION
APOMIXIS-ASEXUAL REPRODUCTION Asexual Reproduction: method of reproduction in which individuals develop directly from specialized or unspecialized parts of single parent without production and fusion of sex cells or gametes. Slide 42: Apomixis paths The sexual life cyle of flowering plants and the apomictic reproduction by seed which occurs when the sexual life cycle is short-circuited (after Vielle-Calzada et al., 1996). SHOTR CIRCUTTED Slide 43: POTENTIAL: Hybrid Seed Production GMS Slide 44: END SHOW POTENTIAL: Hybrid Seed Production CGMS Slide 45: POTENTIAL: Hybrid Seed Production CGMS Slide 46: END SHOW POTENTIAL: Hybrid Seed Production DETASSELING Slide 47: POTENTIAL: Hybrid Seed Production CGMS-SI-A COMPARISON Slide 48: END SHOW Protogyny: hybrid seed production USING PROTOGYNY Slide 49: POTENTIAL: Hybrid Seed Production X X X X F1 apomixis F1 FLOWER : FLOWER FLOWER : FLOWER FLOWER : FLOWER Parts of a typical papilionaceous flower Slide 53: FLOWER Monadelphous androecium Slide 54: FLOWER Slide 55: FLOWER REPRODUICTIVE ORGANS OF BRASSICA FLOWER Rape seed and mustard Slide 56: FLOWER Slide 57: FLOWER Slide 58: FLOWER Slide 59: FLOWER The Heteromorphic system is also called as Heteromorphic sporophytic system. Pin is of ss genotype and thrum is always Ss. The only compatible mating is between Pin X Thrum or Thrum x Pin. Slide 60: FLOWER In this system, the genetic makeup of gametes (male and female) controls the incompatibility reaction. If the genotype of pollen is different from the genotype of ovule, it would grow. Both the alleles show co-dominance. S1 pollen would not grow on S1 stigma (S1S2 or S1S3 or ….. S1Sn genotype of ovary); S4 pollen would grow on S1S2, S1S3…..S1Sn (except S1S4). Slide 61: FLOWER In Sporophytic Homomorphic incompatibility, alleles show dominance relationship as S1 > S2 > S3 > S4 . …………. > Sn. For example the S1S2 maternal genotype would behave as S1 and S12 or S1S3 or ….. S1Sn male genotype would behave S1, therefore, would lead incompatible reaction (see above). Slide 62: FLOWER Slide 63: FLOWER Slide 64: FLOWER Table1. No. of single and double crosses Slide 65: FLOWER Slide 66: FLOWER Slide 67: FLOWER Slide 68: FLOWER Slide 69: FLOWER Slide 70: FLOWER Slide 71: FLOWER