STRATEGIES FOR
ENHANCEMENT IN FOOD
PRODUCTION

PLANT BREEDING

DEFINATION

plant breeding is a technique of genotypic
improvement of economically important
crop plants to produce new crops that are
better suited for cultivation,give better
yeild and are disease resistant

OBJECTIVES

high yeild

resistance to diseases and pests

eary maturity

abiotic resistance

better quality

better adaptability

MAIN STEPS IN BREEDING

GERMPLASM COLLECTION FOR
VARIABILITY

The sum total of all alleles of the genes
present in the existing and past varieties of
a crop and its wild relatives constitutes the
germplasm

all cultivated improved varieties

improved varities that are no mor in
cultivation

old local or desi varieties

pur lines produced by plant breeders

wild species related to the crop species

Centres for plant genetic resources

indian

International Crops Research Institute for
Semi-Arid Tropics (ICRISAT

Central Rice Research Institute(CRRI)

International

International Board of Plant Genetic
Resources (IBPGR)

Types of Seeds

Orthodox Seeds (-10° to -20° C)

Recalcitrant Seeds (aerobic humid
conditions)

Cyropreserved (-196° C)

EVALUATION AND SELECTION OF
PARENTS

The germplasm is evaluated and
plants with desired combinations of
characters are identified. selection is
carried out for plants with
advantageous charaters based on
phenotypic characters

Mass Selection

cross polinated plants

grown in same field

plants selected for desired features and
their seeds are collected

the process is repeated many times to
obtain homozygosity

Pure Line Selection

self pollinated crops

plants selected on basis of best agronomic
characters

sown in separate rows

process repeated continously to obtain
pure line

Clonal Selection

plants that multiply by vegetative
propogation

helps in conserving hybrid vigour and
quality of crop

new genetic variability cannot be
introduced

CROSS HYBRIDIZATION BETWEEN
SELECTED PARENTS

PROCEDURE

Selection and Isolation ofmplants

emasculation (stamens removed at bud
stage)

bagging

tagging

pollination or crossing

STEPS

step 1: pollen grains from the desirable
plant chosen as male parent are collected
and placed on stigma of flowers of female
parents

step 2: Not all hybrids show the desired
characters. only, one in a few 100 to 1000
crosses show the desirable combination.
such hybrid plants are sleceted

TYPES

Intravarietal: same variety

Intervarietal: different lines or varieties of
the same species

Interspecific: different species

Intergeneric: different genera

SELECTION AND TESTING OF SUPERIOR
RECOMBINANTS

STEPS:

i) Selection of haploid plants that have the
combination of desired characters

ii) Selfing the selected plants through
several generations to produce uniform
homozygous inbred lines

iii) Crossing the selected inbred lines to
produce uniform F1 population with
desired qualities and then F1 seeds can be
directly grown

TESTING RELEASE AND COMMERCIALISATION

MULTIPLICATION OF IMPROVED SEEDS

National Seeds Corporation
(NSC)streamlines raising seeds of
improved varieties

free of weed seeds

free of pathogens and pests

high order of purity

high rate of germination

Seeds are certified and packed in sealed
packects as certified seeds. Each sealed
packet caonatins information:

date of test

purity of seeds (99%)

absence of weeds and presnce of inert
matter (not more than 1%)

special features (if any)

validity of certificate

EXTRA TERMS:

INBREEDING DEPRESSION

genetically similar plants produce
reccessive traits in their progeny

reduced biological fitness in a given
population because of interbreeding
among related indiviuals

HETEROSIS/HYBRID VIGOUR

better yeilding varieties in plants in terms
of growth,size,climatic condition

when such hybrids are produced,they are
better than parents and continue to be
cultivated

HIGH YEILDING (HYVs)

Wheat: Kalyan Sona,Sharbati Sonara

Rice: Jaya, Ratna

Maize: Protina

Sugaecane: Saccharum officinarum

Millets: Hybrid Bajra (PHB,BJ,BK) and
Jowar (CSH series)

PLANT BREEDING FOR DISEASE
RESISTANCE

ANIMAL HUSBANDRY