1. The document discusses pedigree analysis and various plant breeding methods such as pedigree selection, bulk population breeding, and backcross breeding. 2. It describes the procedure from hybridization of parental plants to generating F1, F2, and subsequent advanced filial generations, conducting yield trials, and ultimately releasing a new variety. 3. Modifications to the traditional pedigree method are suggested to improve selection for competitive ability and identity of selected plants, such as raising populations under both spaced and drilled conditions starting from F2.

1. O.U.A.T
PLANT BREEDINGASSIGNMENT
ON
PEDIGREE ANALYSIS
SUBMITTED BY:-
DHARITRIRAUL
ADM.NO.:-16HO/16

2. SEGREGATINGGENERATIONS:-
 A segregating population can be defined as “the
genetically diverse progeny from crosses between
parents that differ for one more traits that are under
genetic control”
Confirmation of crosses is critical to success
– Easily observable phenotypic traits such as cotyledon color of
the purported hybrid seed is a common approach.
– Comparisons of the F1 hybrids grown in the presence of the
parental plants
– molecular markers can be used if facilities are available
• maintaining the identity of parental plants and
parental seed is a must for a successful pre-breeding
program .

4. PEDIGREE SELECTION:-
Pedigree selection also known as line breeding .
• Is one of the earliest breeding methods to be used
following controlled crossing.
• Requires record keeping for each of the plants
selected in each generation – so method is labour
intensive
• Method is not amenable to large populations.
• Has the advantage of being able to focus the
breeding program on specific traits.

5. Bulkpopulationbreeding
• Often the method of choice when
– large population sizes are needed to combine a number of
genes for a particular trait, and
– where the goal is to combine genes for several traits.
• Goal is to inbreed the segregating population to
homozygosity
– After homozygosity is reached (F4 or later generation),
intensive selection is practiced for the traits of interest
• With the procedure, seed used to grow each
inbreeding generation is a sample of that harvested
from plants the previous generation
• Advantage of minimal record keeping and can be
used for rapid generation advance

6. Backcrossbreeding
• Often the method of choice for introgressing genes
from wild and exotic germplasm sources
• Backcrossing is a well-known breeding strategy that
ensures the efficient transfer of the gene of interest
from the donor parent to the genetic background of the
recipient parent
• In doing so, the genetic makeup of the
donor parent is greatly reduced while the
genetic makeup of the recurrent parent is
recovered .

7. MANAGINGOF SEGREGATING
POPULATION:-
Managing segregating populations of clonal and apomictic
species .
• Some very important crops such as potato, sugarcane
and many tree fruits are clonally propagated.
• Another group of crops, especially some of the forage
grasses are propagated through apomixis (seed
production without pollination).
• With these methods of propagation, highly uniform
populations in early generations following crossing can
be developed.
• In cases of apomictic species including some grasses,
uniform populations of heterozygous plants can be
developed and put to immediate use as improved
cultivars.

11. PROCEDURE:-
 Hybridization:
 The selection of parents to be used in a cross is the most important step in a
breeding programme based on hybridization. The selected parents are crossed to
produce a simple or a complex cross.
 F1 Generation:
 F1 seeds are space planted so that each F1 plant produces the maximum F2
seed. Generally, 15-30 F1 plants should produce enough seed for a good F2
population size.
 F2 Generation:
 In F2, 2000-10000 plants are space planted to facilitate selection. About 100-500
plants are selected and their seeds are harvested separately.
 F3 Generation:
 Individual plant progenies are space planted; each progeny should have about 30
or more plants. Individual plants with desirable characteristics are selected from
superior progeny. The number of plants selected in F3 should be preferably less
than the number of F3 progenies. If the number of superior progenies is small the
whole cross may be rejected.
 F4 Generation:
 Individual plant progenies are space planted; again desirable plants are slected
mainly from superior progenies. The no of plants selected in F4 is generally less
than that of the F4 progenies

12. F5 Generation:
Individual plant progenies are planted according to the recommended commercial seed rate.
Often three or more rows are grown for each progeny to facilitate comparison among
progenies. The number of progenies must be reduced to manage the size in preliminary yield
trials which is usually 25- 100 progenies.
F6 Generation:
Individual plant progenies are planted in multi row plot and evaluated visually. Progenies are
harvested in bulk since they would have become almost homozygous. The progenies which are
reasonably homozygous and have enough seed may be planted in a preliminary yield trial and
inferior progenies are eliminated.
F7 Generation:
Preliminary yield trials with three or more replications are conducted to identify few superior
lines. The progenies are evaluated for plant height, lodging and disease resistance, maturity,
etc. Standard commercial varieties must be included as check for comparison. Two to five out
standing lines if found superior to check would be advanced to the coordinated yield trials.
F8 – F10 Generation:
The superior lines are tested in replicated yield trials at several locations for desirable
characters. During these trial lines are evaluated for yield, disease resistance, maturity, etc. a
line that is superior to the best commercial variety for yield and other characteristics would be
released as a new variety.
F11 Generation:
In F11 generation released var. is multiplies for distribution to the farmers. The breeder is
responsible to supply the breeder seed to the N.S.C for production of foundation seed.

18. MODIFICATIONSOF PEDIGREE
METHOD:-
 A dismal 81% failure of newly bulked lines against checks was
observed in Indian wheat material evolved by the pedigree
method. This is considered to be the consequence of selection in
space planting in early generations followed by yield tests in a
competitive environment which did not allow any scope of
selection for competitive ability. Thus, most of the homozygous
lines, which were until now raised and carried forward under
space planting, failed to compete with the checks for yield in
close planting. It is, therefore, necessary to modify the method to
combine both the competitive ability and identity of selected
plants. The proposed modified procedure involves raising the
population under spaced planting as well as under drilling from
F2 onwards. Evaluation for tiller index marks an important step.
On the basis of tiller index, single plants are isolated from spaced
populations. Steps of the modified procedure are outlined in
detail. The modified method, which economises on breeders'
workload and other physical inputs, besides having other
advantages, can also be used for certain other grain crops.
Preliminary results based on the modified method during the past
two seasons have indicated its utility.